Anyone have a 4L80E program?

[Telco]

I'm putting a 4L80E in my 2000 Silverado Z71 4x4 with the NP241 transfer case in place of the 4L60E. This is an Autotrac truck. Has anyone got a 4L80E file they can send me that will work in this truck?

The trans is being shipped to me next week along with a rebuilt transfer case modified to accept the 4L80E output shaft. It'll take me a week or three to get it installed as I'll only be working in the evenings, so I have at least that long to get the new segment loaded into my program.

I've also had a custom crossmember made up, and the shop that made it is planning to sell them once we verify that it works in mine. I can post up pics and a link to the shop once it's finalized for anyone interested. This is not a modified stock crossmember like what PATC sells, it's (at this time) a one-off piece formed of square tubing. I won't post pics until it's been installed though, in case there are any bugs to work out.

Thanks in advance, guys.

[Taz]

Hello Telco,

Glad to hear you got a handle on the Camaro shifting issue. What OS is the Silverado using ? As I'm sure you know, changing from a 4L60E to a 4L80E requires a repin of the transmission harness, and the addition of a second VSS - for input shaft speed.

For tuning files check www.holdencrazy.com (http://www.holdencrazy.com) there should be several compatible tunes for your Silverado with a 4L80E trans.

Regards,
Taz

[5.7ute]

Telco, PM lextech or hquick as they have both been playing around with this type of conversion.

[Taz]

The conversion is straight forward, and a great opportunity to practice how to effectively interpret wiring diagrams, and put a manual to good use.

The first purchase that should be made at the outset of any project is an OEM quality service manual - but few people actually do this.

Regarding a 4L60E to 4L80E swap …..

The 4L60E and 4L80E use the same transmission control connector - just wired slightly differently (20 pin female connector)
· the 4L60E uses 13 pins in this connector
· the 4L80E uses 11 pins in this connector
· 10 pins are common to both (between the transmission and PCM)

When converting the harness from a 4L60E to a 4L80E - remove 2 pins (not used) and move 1 pin to a new location.

Adding the “front” VSS connector for the input shaft of the 4L80E is equally straight forward. The two wires from this new connector both go to the C2 (RED) PCM connector.


Regards,
Taz

[Telco]

Excellent. It looks like file name 2000 Chevrolet Silverado Truck Automatic LQ4 6.0 Litre (09381344).tun should work. I've got a factory 2000 computer in the truck. The new FLT level 3 trans with the TCI low gear set is sitting on my garage floor right now (on a pallet) and I went the lazy way and got a Speartech conversion harness. Since I intend to use this for towing, and it's the wife's rig, I went with a stock level torque converter. FLT sent me a TC that will correctly match the older style 4L80E to my 5.3L engine without having to change the flywheel.

I'll also post up some pics of the job as I had a guy out of Dallas make up a custom cross member for me. If it works out correctly, he plans to sell them. I'll post all that when the time comes. This is not a modified factory cross member, this is a custom piece made of rectangular steel.

[Telco]

UPDATE - Thanks to this thread (http://forum.efilive.com/showthread.php?4621-How-do-you-do-a-segment-swap) I got my program modded to put the 4L80E in the truck. I've actually got the trans installed, I just have to clean up a few details before it's finished. Thanks for the help guys, every time I come to this site I learn something. I'll stick a link to the swap in here when it's finished.

[joecar]

Thanks for the update. :cheers:

[Telco]

Here's the link to my writeup, it's on page 4. Thanks for the help on this folks. It couldn't have happened without EFI Live.

http://www.pacificp.com/forum/viewtopic.php?t=9577

[killerbee]

Can anyone lead me to a set of TCM tunes for the 4L80E? Holden seems to only have ECM tunes. I am wanting to look at a stock TCM tune for the 6.0 pickup.

[killerbee]

bump. I know there must be a repository somewhere for this.

[joecar]

Hi KB,

I looked on www.holdencrazy.com (http://www.holdencrazy.com) the TCM files have OS id number starting with 2.
I looked inside the 2xxxxxxx files, they all seemed to be either 4L60/70E or 6L80/90.

The visible 4L80E calibrations are identical to the 4L60E.

Differences between 4L80E and 4L60E from TCM perspective:
- truck 4L80E/4L60E unlocks TCC on closed throttle decel whereas car 4L60E keeps it locked;
- 4L80E has single solenoid TCC whereas 4L60E has dual solenoid TCC;
- 4L80E has slightly different shift solenoid sequence than 4L60E.

If you have same OS id's then you can segment swap...
With the LS1 PCM this is easy as car 4L60E and truck 4L60E/4L80E both used OS 12212156.
With TCM this is not so easy (as you have found).

4L60E segment can drive a 4L80E transmission with the addition of 1 relay (shift solenoid) and repinning of two wires (TCC).

Are you looking at a swap...?

[killerbee]

I was just trying to help someone out.

http://www.gm-trucks.com/forums/index.php?showtopic=123115&st=0

Maybe get an education in the process.

Thank You for that information

[killerbee]

Still sorting this out. Do some gas vehicles have a TCM, while others have only an ECM (with tranny tables)?

[Taz]

Hello killerbee,

Took a look at the link to the other thread … 2002 6.0 L (LQ4) with 4L80E. That truck will have a PCM only (LS1-B style) - no TCM. In that model year, if it came equipped with an Allison transmission it would have also had a TCM.

The current ECM & TCM combination began in Gen IV equipped trucks in mid 2007.


Regards,
Taz

[killerbee]

I am getting enlightened a bit at a time. Do you think my assessment of trans temp creep may have been correct?

[Taz]

Didn’t read the whole thread … in 3rd gear TCC release can be affected by temperature. At low % TP apply / release will vary a bit.

Once you’re above 50% TP in 3rd gear TCC application is around 68 MPH (109 Km/h) for “Normal” and “Tow Haul” modes, and may be as low as 25 MPH (40 Km/h) in “Hot” mode.

Above 50% TP in 3rd gear TCC release is around 38 MPH (61 Km/h) in “Normal” and “Tow Haul” modes, and may be as low as 20 MPH (32 Km/h) in “Hot” mode.

The above quoted speeds are from a truck equipped with 29.6 inch diameter tires and 4.10 gears. These speeds will vary with different tire size and gear combinations.


Regards,
Taz

[killerbee]

tow/haul mode?

[Taz]

Sorry … Tow Haul mode is “Performance” mode in the tune …


Regards,
Taz

[killerbee]

Isn't it odd, the allison TCM has nearly no temp constraints, accept for TC warmup defeat.

[Telco]

The new trans and program seem to be working OK, more or less. I am having a bit of trouble with a hard shift on 2-3 and 3-4 in some instances at about 50 percent throttle or so up to WOT. At WOT the 3-4 shift is way too hard, and I'm thinking that a line pressure reduction might be in order. On the shifting, there is a good, crisp, hard performance shift, then there is what I have that feels like it's going to break something. The trans itself is a FLT Level 3 4L80E with a TCI low gear set changing 1st gear from 2.48 to 2.75 and 2nd gear from 1.47 to 1.57. I've attached what I plan to load next to help with the shifting, but it's going to need tweaking. Thanks for any advice.

[Taz]

Shift quality or “feel” is the result of the interaction of desired shift times, trans pressures, and torque reduction. A “built” trans will have had hard parts added that will mechanically increase trans pressures - often requiring some compensation in the tune to arrive at a reasonable shift.

You took the time to post your current tune - will try and take a look at it tomorrow (getting late here).


Regards,
Taz

[Taz]

Just getting started here this morning. Reread your post – didn’t realize the tune you posted was that which you are planning to use to address the shifting problems – which has yet to be implemented in the vehicle.

Either post the old tune, or give that one a try - and then report back with changes / continuing issues.


Regards,
Taz

[Chevy366]

Don't know about those FLT things , who are they ? Any way , with a built trans or a TransGo kit it is best to take everything back to stock calibrations to start with , then adjust from there , as Taz stated .

[ScarabEpic22]

Go back to stock TCM tune and work up from there. Trans builders do things like raise line pressures and change the hole size in the separator plate, so a few actually recommend leaving the TCM tune 100% stock (but I disagree and think it can be better with a little tweaking).

[Telco]

Unfortunately the program I was working with is gone due to some computer problems. But, the program I loaded only changed shift speeds, with no changes to line pressure. With the new program there is no change in how it shifts. Shifting is still fine below 50 percent throttle, too harsh over. The source program for the 4L80E came from holdencrazy.com.

FLT is the guys that supplied transmissions to a fellow named Parish who is supposed to be putting 1200HP to the ground through a 4L80E. As I understand it, FLT honed their skills by guaranteeing that they could build a trans that Parish could not tear out, so every time he tore the trans out they rebuilt it and upgraded what he trashed until he could not trash it any more. What I have is a Level 3, which is supposed to be set up to handle towing and 500HP. The converter is a low stall, supposed to be close to stock. I figured if they could handle this guy's truck, mine should be easy for them.

Here's a vid of the truck, and there are many more on youtube.

http://www.youtube.com/watch?v=hOm6HC_w8C4&feature=related

[Chevy366]

Strange a stock .tun should have tamed it a little .

[Taz]

You’re using an older (2000) 4L80E calibration - which did not appear to be “stock”. I updated the Desired Shift Times, Trans Pressures, and Torque Reduction to those from a stock 2003 LQ4 4L80E two wheel drive truck.

The shifts will probably still be too firm, but at least your “base line” values are now stock.


Regards,
Taz

[slow67]

You’re using an older (2000) 4L80E calibration - which did not appear to be “stock”. I updated the Desired Shift Times, Trans Pressures, and Torque Reduction to those from a stock 2003 LQ4 4L80E two wheel drive truck.

The shifts will probably still be too firm, but at least your “base line” values are now stock.


Regards,
Taz



Also, most builders on recommend a stock to as a starting point.....so that you don't break any parts from too harsh of a shift. A bigger feed hole (for each gear) creates more fluid flow from the same pressure, which is better than more pressure to create the same feel. Also a firm, quick shift is desirable....the stock-like slide into the next gear actually creates more wear and tear as the clutches are actually are sliding instead of grabbing. as long as your line pressure is under ~200 psi at WOT, you probably can't make it shift hard enough to hurt the trans.

It looks like a stage 3 is a rebuild with stock hard parts (all the rotating parts, etc) but with improved hydraulics. I'm not sure what the feed hole sizes are, but you can make the shift from 2-3 as hard as you want....it won't hurt the trans. 3-4 you have to be a little more careful, but its still difficult to hurt the transmission.

The weakest part of your transmission is the stock input shaft, these seem to give out around 750hp in a 4000lb car (some more, some less obviously), and then next is the 2.75 low gearset, which is partially responsible your harsh shifting....it is a bigger drop from one gear to the next, so more RPMs are dropped for each shift.

[Telco]

Excellent, thanks Taz!

I agree with the idea of starting with a completely stock program, then working from there. Unfortunately, if the trans pressure readings were not stock, then the 2000 Silverado program on holdencrazy.com's stock program link (2000 Chevrolet Silveado Truck Automatic LQ4 6.0 Litre (09381344) is also not stock. This was where I drew the program from, and I don't know enough about what the pressure should be to mess with them yet so those line pressures came directly from that program. This also means that whoever manages the holdencrazy.com site will need to locate another program to replace that one. Or, I guess that program can just be modded with this new one that Taz generated.

I altered my program with the new line pressures and shift times (I'd already modified the shifting tables with the spreadsheet on this site) so I'll try and get this in and tested tonight.

I'd also like to note, the program I put across may have been one I played with the shift times and speeds, but the shift pressures were definitely not touched by me.

On the low gear set, I am coming from a 4L60E which has an even sharper drop, so this trans should feel a bit smoother to me behind the same engine. The shifting issue was more of a jerky hard shift, not one associated with missing a gear between 1st and 2nd which is what the 4L60E was like. Since my truck has almost 32 inch tall tires and 3.42 gears I needed the extra help in first. I am SOOO glad that 4LPOS60E is behind me now though!!!

[Taz]

Hello Telco,

It was the Desired Shift Times in the tune you posted which varied greatly from stock - but I now realize you had altered them - which explains that variance.

The other parameters may have been stock, just in an older tune - GM often updates these after production. I updated these from a newer tune to afford you the benefit of refinements GM made to the 4L80 calibration in subsequent years.

Hopefully it will be a reasonable starting point for you.


Regards,
Taz

[Telco]

I've run the new program, same issue. I called the builder, who advised that the transmission was built to have a firmer shift with the stock program, and recommended dropping trans pressure in the program by 10 percent. I don't want to screw this up, so what fields would I use to drop pressure? I'm thinking that I would want to drop pressure on the base pressure map. Thanks.

[joecar]

Yes, the base shift pressure tables, D0701, D0702, D0703.

[Telco]

Excellent, thanks. As soon as I get my laptop operational again, I'll give this a shot and report back either way. Slowly but surely we're getting there. :thumb_yello:

[6t7gto]

Hello,
i don't mean to hijack this thread but could someone point us in the right direction for programming a TCM from a diesel 4l80e so we could but it behind a gas 350 sbc.
thanks,
david

[Taz]

Hello 6t7gto,

Sounds like an interesting mix and match of parts. What year / vehicle is the 4L80 from ? Is the "gas 350 sbc" a fuel injected Vortec variant, an LS1, or a Gen I with a carb ?

If the engine you're using is a fuel injected Vortec or LS1 - then an LS1-B style PCM would be the most simple / easy controller to use. It would control both the engine and the transmission.

From a "hard parts" perspective - the torque convertor in the 4L80 may have a lower stall speed than is optimal - given that it came from a diesel application.


Regards,
Taz

[6t7gto]

Hi Taz,
thanks for the reply.
we are putting it in a 75 corvette which has no computer whatsoever.
the motor is the original 75 350 carburated.
we were told a diesel TCM is a standalone controller but it would need to be reprogrammed.
Having trouble finding someone to do that.
we know there are aftermarket controllers but not inexpensive.
I have read about TCM's from the boneyards going for $25.00.
But we need it programmed.

p.s.
we got the motor(TBI) and 4l80e as a package. early 90's pickup truck.
we have the whole harness and computer (16147060)

david

[Taz]

Hello David,

OK … I think I understand now. The project vehicle is a 1975 Corvette with the original carbureted Gen I 5.7 L. The 4L80E transmission and wiring harness is from a 1991 to 1995 TBI (gasoline) truck.

Regarding your diesel controller question ….. historically some companies (e.g. Art Carr) used a stock diesel truck transmission computer with a “custom chip” and wiring harness - for stand alone operation of the 4L80E. The down side to this technology was that these were not easily programmable - as a “new” chip had to be burned each time the tune was modified.

These types of controllers are still available, and are $350 plus - for the computer and custom chip (without the harness).

These early TBI controllers did not have a “flash” style memory (they used a chip) and therefore cannot be tuned / modified via EFILive software.

Fast forward a decade … the controller and harness from COMPUSHIFT is fully programmable - but well over $1000.

The good news is that the 4L80E transmission from 1991 (first introduced) through to 2004 remained virtually unchanged.

You could try building your own stand alone controller using your existing wiring harness and an LS1-B style PCM. The PCM would require MAP, TPS (sensor available for Holley carbs), VSS, and RPM input - to effectively control the transmission. Obviously, you would have to disable most of the engine related functions and DTCs - when constructing the custom tune.

The upside to this approach is that the controller (PCM) would be easily tuneable / customizable via EFILive software. Additionally, to operate a cable driven speedometer, a modified tail stock housing would be required.


Regards,
Taz

[6t7gto]

Good morning Taz,
Well, we have ONE of those problems addressed...I have an electonic speedometer from another project that I am planning to use. :)
Who/where would we get the remainder of the parts?
david

[Taz]

Hello David,

Where this project leads you, is up to you. Below are three possible options, including part numbers (where available), and possible retailers - intended as a reference only, not an endorsement of any company.

Option 1 - reuse your existing harness, and purchase a compatible controller and a custom chip

Street & Performance - computer service # 16196395 or 16197327
Street & Performance - custom computer chip

Option 2 - purchase a programmable controller and compatible harness

GMPP controller and harness kit – part # 19212657
TCI controller (part #377500) & TCI wiring harness (part #377502)
Compushift (Hughes Performance) controller and wiring harness – part # 25-100


Option 3 – design & build your own controller system – reusing your existing harness

LS1-B style 512Kb PCM (service # 09354896 for 1999 & 2000, service # 12200411 for 2001 & 2002)
PCM wire terminals (may or may not be required) - Delphi Micro-Pack 100W (available from EFI Connection - part # 100-00176 or 100-00177)
stock tune from a 2001 or 2002 Express / Savana with a 5.7 L Vortec and 4L80E transmission
EFILive software
plenty of time and patience

Regards,
Taz

[Telco]

Update - My laptop is still crapped out, but good news! My wife's laptop just crapped out too! I swapped her hard drive and memory into my laptop, and between the two we now have one working computer! I keep all my programs backed up, so I've not lost anything. Barring any further distractions I'm going to try fiddling with the program tonight so I can get the shift pressures lowered.

[slow67]

Baumann has a more budget friendly Transmission controller (yes they have one for a 4L80E too). Megasquirt also has 2 4L80E controller (GPIO and another alpha version based on MS2).

I used to have info on using the GM Diesel controller, but I can't find it anymore.

[Taz]

Baumann's stand alone 4L80E controller is $400 - just for the controller. That price is about the same as other similar offerings from other various companies.


Regards,
Taz

[6t7gto]

thanks for the replies.
david

[slow67]

With a harness, the Baumann is around $525. Cheaper than TCI, which is around $740.

[Telco]

Update - I've redone the trans shift pressures with a 2004 Caddy Escalade program, which changed things but still has the jerking. I then dropped 10 percent off from there, and this has worked wonders for it. I still have the problem, but the "window of opportunity" is a lot smaller and is not nearly as intense. Right now we have ice on the roads due to a cold snap so it's hard to really test properly.

[joecar]

Try adding Shift Torque Reduction back in.

[Telco]

I can give it a try. Question, if the number is larger is pressure greater? The wording in the information field for the base pressure is a little confusing. I'm also guessing that one attempt took the numbers too low, because on that attempt the trans wouldn't shift properly at all at WOT. That program has been removed.

[Taz]

The values for the shift Base Pressure (D0701, D0703, D0703) may range from 0 to 96 PSI. The higher the value, the greater the pressure.

The values for Torque Reduction (D0801, D0802, D0803) are the percentage that you wish the torque reduced on upshift - at a given delivered engine torque level.


Regards,
Taz

[Telco]

Hi guys, update: I'm getting close. The guys at FLT actually had a buddy that uses EFI Live, and they had him take a look at the program. They didn't get it perfect, which I wouldn't expect from a blind program, but the tune is a lot closer than it was. I think I can get it the rest of the way. And in a couple of weeks, I swap in a new engine. I have a 4.8L at the rebuilders now, and it should be ready to start the installation around the first week of April. I can't wait.

If anyone needs a really good transmission built by guys that go above and beyond, Finish Line Transmissions is definitely my #1 recommendation. I am as satisfied with my FLT transmission as I am with EFI Live.

[joecar]

Thanks for the update.

FLT put very good quality/detail into their builds, and they have a very cool trans dyno.

[Telco]

Update - Danged if I can figure it out, but I can't get the program to smooth out. So, I started reading up more on it on this site. Then it struck me - the engine is old and has problems, has vacuum leaks, ect. From what I've read, these leaks are probably causing my problems since the computer isn't getting signals consistent with what the engine is doing. No problem though, my new engine is sitting down at the rebuilder as I type this, and with any luck I'll be slapping it in there around the start of April. Hopefully, when all the mechanical problems are resolved, I'll be able to get the programming straight.

[ScarabEpic22]

Just found your file from earlier in this thread, I see your truck is a 2000. Why not use an OS from 2002 like the popular 12212156? It should be more refined than the 2000 OS plus if you ever want to go to a COS its easy. Not sure you want to add another thing into the mix right now though!

Attached is a stock 02 12212156 OS file with a freshly copied 4L80E trans and trans diagnostic segment. I also put your VIN in, but didnt change any of the tables around. If it works for ya, great! The IFR is different between your tune and this one so I knew there would be a few things to move around. If you want to use it, open your old file and this new one and copy all the values from the 2000 tune to the 02 one.:rockon:

(BTW, are there any advantages to running say an OS from 03 vs 02 in a 512kb PCM? I know most people use the 12212156 OS because its great for Vortec swaps with the Express van tune, but what about regular trucks?)

[Telco]

I can give it a shot. I'll report back on the results.

Incidentally, I've been trying files from up to 2007 trucks. Haven't been able to find a newer file than that with a 4L80E, seems everything newer that HoldenCrazy has a file for either has a 6 speed auto or a manual trans.

[TIM Z]

Hi Telco!

Did you get your problem figured out?

I am very interested in the outcome.

I also have a 2000 Silverado Z71, with 6.0 engine, comp cam, Eaton TVS 1900 supercharger.

Ive been thru 4 - 4L60E's in the last 1000 miles!!!

I am swapping in a 2004 model 4L80E as we speak.

Im in need of help with adding the 4L80e segment to my custom tune.

Can someone help me here and do the segment swap for me with my attached tune?

Im just too nervous right now to fumble thru it as ive spent lots of money lately on this truck and i would have a heartattack if i broke anything else!

Any help is appreciated!

Thankyou in advance.

[ScarabEpic22]

Fix the out of range cells first man, there are a LOT of them!

If you can find a tune with the same OS as yours with 4L80E I can do a seg swap for you, if not then you might have to go to a different OS that has a 4L80E tune available to do a segment swap. Like a 2002 OS.

[TIM Z]

Fix the out of range cells first man, there are a LOT of them!

If you can find a tune with the same OS as yours with 4L80E I can do a seg swap for you, if not then you might have to go to a different OS that has a 4L80E tune available to do a segment swap. Like a 2002 OS.

Thankyou for the reply, your time, and offer to help. I really appreciate it!

Not sure how to fix the out of range issues, Im afraid to change anything that may mess up the tune, the truck runs awesome and has great A/F ratio .

( I wander That since my tuner uses Tunercat and HP tuners to tune my truck, and since i copied the tune into my EFI LIVE software that this is why values are out of range?? )

I Guess i need to find somewhere that has a 4L80E OS thats the same as mine?? Maybe holden crazy, i will do some looking.

Thanks again for the help.

[TIM Z]

OK i found The same operating system for a silverado with 6.0 and 4l80E , a 2000 model year, On holden crazy. Hope this is the correct file.





Thankyou. I will work on getting the out of range parameters delt with!

[TIM Z]

Ok, I got it figured out after some searching and reading!

I found the segment swap sticky at the top of this section ( Imagine that !! ) How cool, it was easy!!

Thankyou all for the help in the meantime. Im really excited to be doing " stuff" like this as i am such a newb and scaredy cat when it comes to adjusting my tuning!

[joecar]

Fixing Out Of Range Cells:
showpost.php?p=87052 (http://forum.efilive.com/showpost.php?p=87052&postcount=14) post #14
showthread.php?14119-3000-RPM-max-and-setting-codes-03-Z06-with-Magnuson-at-150kPa (http://forum.efilive.com/showthread.php?14119-3000-RPM-max-and-setting-codes-03-Z06-with-Magnuson-at-150kPa) posts #14, #17
showthread.php?14654-I-need-help-getting-the-most-out-of-my-car (http://forum.efilive.com/showthread.php?14654-I-need-help-getting-the-most-out-of-my-car) post#2

[TIM Z]

Thankyou joecar, i will look at this info. Appreciate the help.

[Telco]

Hey folks, I think I found the problem! I updated the Force Motor Current fields D3802 and D3803 with the one from a Camaro with a 4L80E from the HoldenCrazy modified files, and it fixed 90 percent of the problems. Unfortunately I won't be able to continue tuning the trans right now, as tomorrow I start putting a new engine in the truck. The shift speeds are off, as are the kickdown speeds, as I am still having an issue with vacuum leaks screwing with things. Well, I won't be by the end of the week, but up till now... Anyway, included is a copy of the new file I'm using at the moment, if anyone else is having similar problems and wants to give it a shot. I still plan to put the finished file over to holdencrazy.com when I get it worked out. I've gotten tons of help here, the least I can do is give a little back. Please note, this file does not have a stock 4L80E gearing, I'm using the 2.75 first and 1.58 second gears in this trans. If you have a stock 4L80E I'd not use this program.

10379

[joecar]

Telco, set D0960-D0962 Throttle Kickdown tables to 100% all cells; this will avoid conflicts with the PT Upshift/Downshift tables.

[Telco]

K, once I get the truck back on the road (engine swap in progress) and get the segment copy issue worked out (http://forum.efilive.com/showthread.php?15972-Segment-copy-problem&p=142525&posted=1#post142525) I'll make sure to adjust per your suggestion. Thanks.

[Telco]

Hey question guys. I was just correlating the old program to the new so I can get the shift points more or less correct, and just discovered on the old program that field H0104 was incorrect. According to the program,

"The number of revolutions per mile of the transmission output shaft.

For manual vehicles, it is not used and is often set incorrectly.
For automatic vehicles, it is used by the PCM to determine the transmission shift speeds.

It will normally be consistent with the equation: H0101=H0102*H0104."

On the old program, H0101 is 88956, calculated according to the tire diameter, which is correct. H0102 is 40, which is a set number. Since H0101=H0102*H0104, it also means H0101/H0102=H0104. H0104 should be 2223.9, but the program shows 2790. Might this have been causing my strange shifting parameters? When I put the tire diameter in for the new program from scratch, the numbers calculated the correct values for all three fields.

[joecar]

That may have been the cause of the shift points being out.

[Telco]

Sweet. I'm really looking forward to seeing how the new program goes with the new engine.

[Telco]

Just found your file from earlier in this thread, I see your truck is a 2000. Why not use an OS from 2002 like the popular 12212156? It should be more refined than the 2000 OS plus if you ever want to go to a COS its easy. Not sure you want to add another thing into the mix right now though!

Attached is a stock 02 12212156 OS file with a freshly copied 4L80E trans and trans diagnostic segment. I also put your VIN in, but didnt change any of the tables around. If it works for ya, great! The IFR is different between your tune and this one so I knew there would be a few things to move around. If you want to use it, open your old file and this new one and copy all the values from the 2000 tune to the 02 one.:rockon:

(BTW, are there any advantages to running say an OS from 03 vs 02 in a 512kb PCM? I know most people use the 12212156 OS because its great for Vortec swaps with the Express van tune, but what about regular trucks?)

Scarab - I tried using your program but my computer would not accept it. Guess it's not going to work. Thanks though.

I did get the engine running, finally. There's still a lot to be done yet though. Initially I had misfiring on two cylinders, found them to be a couple of defective injectors so I've got six 5.3L injectors and two 4.8L injectors in the truck right now. It doesn't seem to be affecting anything badly since the engine is a 4.8L, but I'll be swapping all the injectors with new ones as soon as I get enough scratch together. Still have to track down an oil leak, and get the wideband wired in.

[Taz]

Hello Telco,

Take a look at the part number on the original 4.8 L injectors, and the 5.3 L injectors you have intermixed - these maybe the same. GM generally used the same injectors on 4.8 / 5.3 / 6.0 L engines within the same model year, and often over several model years.


Regards,
Taz

[Telco]

My dad mentioned that to me last night. I plan to check it out this evening. Thanks.

[ScarabEpic22]

Telco, did you full flash the file I created for you? If you did not, then its not going to work because the trans segment is for an 80E not a 60E.

[Telco]

Yes, I tried the full flash (fat red arrow) but the computer wouldn't accept it. Said it wouldn't match. So instead I moved files from one to the other last night. It's working well enough at the moment, at least enough to let me get it broken in and get the wideband installed. When the exhaust was put on they installed the bung for it. Right now I've got one of the old O2 sensors with the wires lopped off plugged into the wideband port so as to not damage the sensor by running it unpowered. Eventually the ash tray will become a plug center for the wideband/laptop interface.

I'll still be wanting to try and make that program work if possible though, because when I get things tuned in and working I still want lean cruise.

What's in there now though... man oh man. I took it out for a ride yesterday. Nothing hard since it's not broken in yet, but getting up the interstate onramp at about 35-40 percent throttle it broke the tires loose. This is with 3.42 rear gears with an Eaton posi and 265/70R17 tires, 31.7 inches in diameter. I was very surprised and am really looking forward to getting it tuned in.

[Telco]

Question, how can I correlate a shift to the Force Motor Current fields D3802 and D3803? I tried doing a scan then playing it back with the tune up, but it didn't show anything that I could see. By playing with this field primarily I'm getting the trans to shift the way I want it to for the most part but now I'm getting to where I need to be able to fine tune.

[Telco]

Anyone? Anyone? Bueller?

[Taz]

Hello Telco,

As a disclaimer … I am neither an engineer nor a transmission expert … the following is based on my understanding of the operation of A4 (4L60E / 4L80E) transmissions and past tuning thereof …

The newest technology transmissions (6L80 / 6L90) are fully electronic. Older transmission (TH350 / 700R4 / 4L60) were controlled by fluid pressure, fluid flow, and mechanical devices.

The 4L60E / 4L80E are pressure / flow based designs that interface with electronic components to allow PCM control - essentially a hybrid design.

D3082 (Force Motor Current - positive) and D3803 (Force Motor Current - negative) were used in 1999 and 2000 OS and were homogenized into D3801 (Force Motor Current) in 2001 and newer LS1-B PCM OS. I would recommend upgrading your project to use a 2001 or 2002 OS.

The Pressure Control Solenoid (Force Motor) is the “bridge” or “Rosetta Stone” between physical line pressure (PSI) and Amps (a measureable PCM input - used to represent actual line pressure).

The PCS / PCM relationship was calibrated by the OEM at the time of production - unless the relationship has become inaccurate - it should not be altered.

Shift pressures should be tuned via D0701, D0702, and D0703 values. For these tables to accurately adjust shift pressures, D3801 (PCS / Force Motor) table values must be accurate.

As an example, if you wished to command maximum shift pressure of the 3>4 shift (D0703) at a given Delivered Engine Torque value, you would enter “96” in the appropriate cell of the D0703 table - this would command a transmission shift pressure of approximately 203 to 223 PSI (maximum of 235 PSI).

The above would only occur if the D3801 (PCS / Force Motor) table values were accurate. If you look at D3801 (or D3802, D3803) the vertical column on the left is Torque Signal Pressure (PSI), while the row at the top is TFT. This table attempts to equate the physical transmission line pressure (oil pressure) with Amps - to afford accurate (or reasonably accurate) PCM controlled shift pressures.

Arbitrarily altering this table (D3801) would cause the PCM to receive inaccurate data with respect to the actual physical transmission line pressure. This would cause the D0701 to D0703 tables also be inaccurate / unpredictable - effectively rendering commanded shift pressure to little more than guess work.

GM service manuals describe a diagnostic procedure to confirm D3801 calibration - by measuring transmission line pressure with a gauge, while using a Scan Tool to cause very small changes in the amps output by the PCS.

I’ll try and attach some images below …

Regards,
Taz

1141411415

[joecar]

Question, how can I correlate a shift to the Force Motor Current fields D3802 and D3803? I tried doing a scan then playing it back with the tune up, but it didn't show anything that I could see. By playing with this field primarily I'm getting the trans to shift the way I want it to for the most part but now I'm getting to where I need to be able to fine tune.I don't know that you can correlate the force motor current table to a specific shift (or vice-versa)...

while in gear, the PCM calculates and/or looks up the commanded torque signal pressure [we don't have a table for this];

during a shift, the PCM commands the torque signal pressure from the shift tables [D0701, D0702, D0703];

(torque signal pressure: see the Common Functions hydraulic schematic)

in each case, after determining what the commanded TS pressure should be, the PCM maps TS pressure to force motor current using the FM pressure-current table; the TS pressure will be accurate if this table correctly models the PCS/TFM solenoid (i.e. the table has to match the ability of the solenoid);

you can increase TS pressure across the whole range by decreasing the FM table, or by finely screwing in the hex screw on the back of the PCS solenoid... in both cases the FM table is not correctly modeling the PCS solenoid, so you should check line pressure to make sure it is neither excessive nor low during in-gear and during each shift (see the LP tap on the left side of the case).

[Telco]

Well, the problem I'm running into is no two tables have been the same that I've come across for the force motor pressure, so as far as I know I've never had an accurate force motor table. So if I read what the two of you are saying, I should look into having the dealer download a 4L80E program to my truck then, and have them verify the pressure is correct. This would probably be hard to get them to do since the truck came with a 5.3L/4L60E and now has a 4.8L/4L80E and the trans has modified 1st/2nd gears.

I'd love to upgrade to a 2002 program, but was unable to get my computer to accept one. No idea why. I figure on trying again after I get my various engine difficulties worked out. I'm having a devil of a time getting the oil pan to stop leaking. I swear I'm getting to the point of just buying something outright and driving it as-is. This thing's getting my goat big time.

[joecar]

You could connect a pressure gauge to the line pressure tap and use the scantool DVT controls to check that line pressure ranges correctly... this is probably the best way to do it regardless of whether the FM table is correct.

Post pics of your pan...? Are the bolt holes proud (deformed upwards)...? What gasket are yo using...?

[Taz]

Hello Telco,

Sorry to hear frustration is setting in ... we've all been there. Your comments above about resorting to going to a GM dealer for support are not what I was trying to express .. in very plain language - leave the the PCS / Force Motor values stock and tune your shift "feel" via shift pressure, shift time, and torque reduction. You can do this on your own - it will just take a little time.

I generally tune the "normal" shift mode to be compatible with daily driving, and the performance mode (Tow / Haul) for either towing duty or drag strip duty - depending on the intended secondary use.

Regarding your PCM not "accepting" a 2002 OS - if your are using an LS1-B PCM with service number 09354896 or 12200411 - either of these should be compatible with 2002 OS 12212156.


Regards,
Taz

[joecar]

...
tune your shift "feel" via shift pressure, shift time, and torque reduction
...Telco, these^ are the keys, especially TR.

[Telco]

Post pics of your pan...? Are the bolt holes proud (deformed upwards)...? What gasket are yo using...?
Sorry, I don't have any pictures, but the pan was a new GM piece that had the gasket riveted on. The bolt holes are not deformed, the pan surface and engine surface are flat. The gasket called for is an aluminum piece with a rubber ring around it, and the book says to use sealer in the corners.
It would lose a quart over 100 miles of driving. On the plus side, no need to worry about rust under the truck. :doh2: I pulled the pan off from under the truck and used a new gasket, this time with Great Stuff on either side of the gasket. I also let it sit overnight before putting the sealer and new gasket on, and wiped all surfaces down with denatured alcohol until they were oil-free. It doesn't leak as bad now, but it still leaks, hence the engine pulling I'm about to begin. I never have been able to get an oil pan to seal correctly from underneath, but decided to try it again since the design of the GMT800 truck makes it look easier.


... leave the the PCS / Force Motor values stock and tune your shift "feel" via shift pressure, shift time, and torque reduction.

This is what I was expressing as having a problem with. I've looked at a dozen supposedly stock tunes, every single one of them has had widely different numbers for the force motor. I don't know what the stock values are supposed to be to begin with. Since the numbers did vary so much from one program to the next, I decided to adjust using the force motor parameters, and have had the most luck in smoothing shifts out.

I'll try again on loading the 2002 program, it would be preferrable to start with that one from scratch rather than do the 2000 program then start over again with a 2002.

[Taz]

I thought you had been battling a transmission oil pan leak ... sounds like you are describing the engine oil pan. If its the engine oil pan, these must be aligned with the rear block "face" or machined surface - within a fairly tight tolerance - or they will leak and / or cause stress on the transmission input shaft. Its a challenging task with the drivetrain in the vehicle.

Some people will "eyeball" this, others use feeler gauges - I have done both, put prefer to use the proper alignment tools whenever possible.


Regards,
Taz

[joecar]

Oh, engine oil pan... yes, you need the alignment tool, what Taz said.

[Telco]

Oh no, the trans is golden aside from the shifting problem. I'm thinking that the oil pan is going to be a dealer fix depending on what they want for it. I've spent way too much time on it, and need to get on the tuning as well as the crap I've been putting by the wayside to get that engine in.

[Telco]

Oh no, the trans is golden aside from the shifting problem. I'm thinking that the engine oil pan is going to be a dealer fix depending on what they want for it. I've spent way too much time on it, and need to get on the tuning as well as the crap I've been putting by the wayside to get that engine in.

Speaking of time, as always I'd like to thank everyone for the time they've spent helping me work through these little problems. A lot of my frustration with the vehicle project is related to stress from other parts of my life. If it were just the vehicle, no problem.

[Telco]

Update - The oil leak is fixed (turned out to be a PCV system issue) so I'm about to rip the interior out so I can install the wideband the way I want it. Initially the wire will just run to a point where it will hang under the dash but eventually I'm going to convert the ashtray into a cable access point where I can plug the laptop into the wideband with a short cable. I'll also be able to plug a flashdrive into a new stereo later. But I digress. I'm hoping to be able to start on wideband tuning over the next week.

I managed to get the 2002 program loaded into the truck. You have to do a full flash to get it in, not the quickie flash you normally do when tuning. The first problem I had with it is the battery light keeps going on and off and it sets a P1638 code, generator F terminal circuit. I know at some point they went to a PCM-controllable alternator. Is this something I need to put on the truck now, or is this something I can disable? So far I've not found any manipulatable fields for this. Or, will it hurt anything if I just disable the MILs for this? I'm really hoping I can retain the 2002 program for that lean cruise feature.

Anyway, thanks for the help so far and I really appreciate how nobody seems to mind how I disappear for weeks at a time. It's about to get worse too, as the union side of my company is about to go on strike and I'm gonna be working massive overtime covering for them.

[Taz]

Hello Telco,

Yes, an OS change requires a Full flash (OS & CAL). Regarding the alternator, you have two choices. Either set P1638 to "Not Reported", or connected a wire from C2 pin 52 (which will be empty in your current wiring harness) to the alternator "F" terminal (which will probably be marked as "I" on your current alternator connector).


Regards,
Taz

[Telco]

Sweet thanks. If I were to connect the wire as mentioned, what effect would it have?

[Telco]

Also, found that under G1206 there is a field where you can turn Alt Term F on and off. I decided to turn it off to match the old program.

[Telco]

OK, got the battery light knocked out by shutting it off in the program. My truck's not wired for the F terminal connection, so no harm in not having it. I also figured out why I was unable to get the shifting to adjust correctly. I was thinking that fields D0701-3 were indicating how much was to be removed from the base shift pressure, and that a higher number would mean a softer shift. I'm embarassed, but I'd rather show embarassment and prevent others from having problems than keep quiet and let others stumble. So, I'm finally starting to make progress with this thing.

Unfortunately the union guys in my company are striking starting tonight, and we non-union guys are going to be working massive OT to cover until the strike's over. As I'm down to only the truck to drive, the wideband will be having to wait a bit before I can install it. Sucks, but I'm going to run a partial Corvette tune for the engine which the truck seems to like. Thanks for the help folks.

[Telco]

I'm getting this thing close on the transmission. I do have a question on fields D0701, D0702, and D0703. What would I see if the fields were set too low? I know too high is a slamming hard shift. I have the 3-4 shift perfect, and the 1-2 is almost there, but I can't seem to get the 2-3 to smooth out enough. It's halfway there now though, but it seems like D0702 is getting way lower than D0701 and D0703. Just wanting to make sure that too low of pressure won't cause slamming shifts too.

[Taz]

Hello Telco,

Shift time and shift pressure help keep the transmission from slipping. Shift times in the 0.150 to 0.300 second range are a "ballpark" of what generally works well in 1>2 and 2>3 shifts. Shift pressure I ramp up fairly quickly - to prevent slippage.

Slamming shifts may be caused by too much pressure, too soon - but are usually caused by insufficient TR (torque reduction). If you have the TR "zeroed out" it will probably shift far too firmly. Reducing shift pressures simply because you want TR set to "0" puts the transmission at risk, and removes a tuning variable from the table.

Try increasing TR to smooth out your 2>3 shift.


Regards,
Taz

[Telco]

I've got some in there now. I'll add some more in and we'll see what happens then. Thanks.

[Telco]

I added more pressure and more torque management, and adjusted the shift speeds per your recommendation. It made things quite a bit different. But, it did smooth the 2-3 shift out quite a bit. We'll see what a few more hits does with it, thanks.

[Telco]

I've done the above, and now have a rougher shift. Interesting note though, I also noticed that the truck seems stronger with the higher pressures which leads me to believe that lowering the pressure only to improve shift feel was also causing me to lose power in the trans due to slippage. So, pressure too high causes banging shifts, pressure too low causes loss of power transmission to the rear wheels making the engine feel weak. I'm going to try increasing the shift speed time a bit more and add a bit more torque management at the bottom.

What PIDS I would need to watch to tune this correctly?

[joecar]

Include at least these: GEAR, SHIFTLAST, TFMPRS, TRQENG, VSS, RPM, TFT, TCCMODE, TCCSLIP.

Yes, do not let the trans slip... set the shift pressures a little higher and the shift times as Taz said above, and then play with torque reduction to tune the shift feel... you want a firm shift with being jerky.

Make sure your MAF and VE tables are correct to ensure that the in-gear pressures are sufficient to prevent slipping.

[Telco]

Heh heh... I've got an Innovate LC1 in a box right now waiting for installation, but I'm also working 12 hour shifts 6 days a week and have only the truck to get around in. Right now I have just about enough time to tweak the program based on the drive to work and back, then slap the program in and try the next day. If I can ever get another vehicle or get some time off I can get it in and get do the autoVE thing. Until then I'm using a stock 4.8L table, best I can do at the moment. I'll set up a scan using those parameters and see what I can turn up. I've also picked up a factory manual for the truck so I've got access to what the pressure should read. Thanks.

[Telco]

Found why I wasn't getting anywhere adjusting for the 2-3 shift. Field D0706 had VERY high numbers where D0704 and D0708 didn't. I copied this field from another 4L80E program that didn't have such high numers (as high as 45) and now all of a sudden the 2-3 shift isn't killing me. Now it's giving me a hard shift suitable for the dragstrip rather than the hard jerk suitable for tearing the trans mount out.

I also fiddled with the shift speeds, by pulling up a Corvette program and using the Speedo Calculator, and used the Shift Point Corrector to match them to my setup.

Thanks to the folks here, I'm getting there.

[joecar]

Glad you found it :cheers: thanks for posting back.

[Telco]

I'll do more than that, once I work it out so it shifts properly I'll both post the program here and shoot it over to HoldenCrazy although I'll wait on him until I get the engine programming done as well. :good:

[Telco]

All righty folks, I'm to the point now that things are smooth, and I think I'm ready for fine tuning. I understand that the more pressure the better so long as I don't have so much that I'm breaking parts. Question is, is there a max amount of torque management I need to be using? How much is too much? I've been going off the assumption that 35 percent is the max I need to use.

[joecar]

You can use torque reduction to fine tune the shift feel... you can use more than 35% if you want.

[Telco]

What is the most torque management I'd want to use? 50%? 75%? Thanks.

[slow67]

You just have to try it.....You will know if you went too far, because the motor will misfire.....

[Taz]

I believe some LQ9 equipped Sierra Denali's had TR as high as 65% from the factory.

Slow67 is correct - too much TR may lead to a misfire / back fire condition.


Regards,
Taz

[Telco]

Good deal, thanks. I'll report back what happens.

[Telco]

RRrrrrrr.. seems like every time I get close it falls back out. I have the 1-2 shift perfect, and you can only tell the 3-4 shift by the change in engine tone and the RPM drop. The 2-3 shift is smooth first thing in the morning, but once it warms up I get a clunk in the shift. It only shifts smooth on a WOT shift when warm. What am I missing here? My current parameters are shift speeds are set to 0 on all gears. Temp compensation is in place on the 1-2 and 3-4 shifts, and the table is zeroed out on the 2-3. The shift speed and temp compensation were set to zero in an attempt to eliminate variables. Torque management does little to smooth the shifting out, have experimented with anywhere from 0 to 50 percent TQ. This leaves the 2-3 base pressure table to adjust. I've run the pressure anywhere from 0 to 90 trying to get this thing to smooth out. Is there a possibility that I have a valve body problem? As a reminder, I have a built 4L80E with the low gear set in it. I'd be inclined to blame the low gear set, except it does shift properly when cold and at WOT, and I'd think that a WOT shift would make the problem more prevalent if it was the gearset causing the problem. Any suggestions? If need be I can load my latest program up this evening.

Oh, and is there a possibility that I need to get the VE tables worked out before I can get this to work right? I'm taking the next week off and am thinking that I can get the wideband installed now.

[slow67]

Has your transmission been dual fed? Did your builder keep the 3rd accumulator? What did he drill the 3rd feel hole to?

You might have to log the transmission temp, then dial back the force motor vs. TFT amps. Then up the 1-2 and 3-4 to get them back inline.

[Telco]

I can't answer any of those questions. The directions were to build a 4L80E with a low gear set that would handle up to 500HP for a towing rig that would be driven by a woman. Needless to say the woman is not happy with me right now. I know that they drill holes larger on high performance rigs, are these holes in the valve body? If so I can probably get the builder to send me another valve body. I can't do much with transmissions, but changing a valve body I can do.

[Telco]

Weird. I gave 'er hell on the way into work this morning before it warmed up. This is not something I like to do, but... it shifted really well until it warmed up, then it went back to the hard shifting on the 2-3. It did still have the jerk shift while cold, but it wasn't nearly as bad. Right now my temp compensation table is zeroed out.

[Telco]

WOO WOO! Think I had a House moment, (http://www.fox.com/house/) as it occurred to me that I was adjusting the entire table for the 2-3 shift, but the scan logs show that I'm not hitting the upper end of the torque table. And, it occurred to me that D0702 is not the entire pressure, but is additive to the base pressure field. This was scaring me a bit as I was originally and erroneously thinking that 0 in D0702 means 0 pounds. As soon as this clicked, I adjusted the table for the fields I'm using and dropped the high end way down, and yesterday's program ran tons smoother today. Instead of the jerking shift along the entire midrange, I had a larger smooth shift area, and a NEW hard snap shift like one would expect in an all-out racing effort. The jerk shift range was a lot smaller, and the jerkiness was not nearly as harsh. I'm hoping that today's program will have the issue resolved although I won't be a bit surprised if I don't have some fine tuning to do. Thanks for the patience folks, someitmes it takes me a little longer than it should.

[joecar]

Hi Telco :cheers: good job

Post a pic of your table.

Look at items 1c and 1a in this: 4L80E-Reference-Material - Common Hydraulic Functions (http://forum.efilive.com/showthread.php?4305-4L80E-Reference-Material&p=39471&viewfull=1#post39471)

torque signal pressure adds to line pressure.

[Telco]

I'll do you one better. Here's the tune I'm going to load in for tomorrow's check. The one I ran today still shifted too hard, but the clunking shift was virtually nonexistent. I'm also happy with how the rest of the program is. The shifting and kickdown are all working beautifully.

I'm so glad this is finally starting to work out.

[Telco]

OK folks, I feel confident enough with this tune to post it up for anyone to use. Anyone that wants to run a 4L80E from FLT with the TCI 2.75 first gear and 1.57 second gear, this tune is almost perfect. Use the trans segment out of this and you should be close enough that you just have to fine tune to your own tastes. It works well in my 2000 Silverado, with a 2002 program. When I get the engine tuned, I'll be posting it here at EFI Live and will be submitting it to holdencrazy.com for their modified tune bank. What goes around, comes around. :grin::rockon: Course, I'll miss how the poorly tuned program would bark the tires on every shift (even the 3-4 shift at about 85MPH) but the tune that's in there is far easier on the truck. Who knows, when I get the BCM fixed so the tow-haul works again I might bump the tune up a bit for the tow/haul mode and rename it the fun button. :sly:

Thanks for all the help on this folks, I'll be back later on when I get around to getting the wide band installed. Unfortunately we're down to one vehicle right now, so I can't take the truck down to do the job the way I want to.


Anyone who used the program that used to reside here, don't. It was compensating for incorrect parts.

[Telco]

Hey guys, long time no post. I know how much it sucks when there's a problem and the resolution never gets found out, so...

After getting nowhere with my oil leak issue, I sent my engine back to the builder to find out what the deal was. He found some metal somehow got wedged into a valve, and some incorrect bolts installed in the main bearing caps. All this is supposed to be fixed now. I'm highly pissed about it but at least the builder worked on it again and found problems. I'm working on putting the engine back in now.

Now then, to the subject of the post. Since I was pulling the engine out anyway, I also sent the trans back to Finish Line Transmissions to have them look at the hard shifting problem. Chuck pulled it down, and apparently the 2-3 plate was drilled for a full-out race trans. The pressure reduction I had to do to get it to shift right also caused 3rd gear to wear. Chuck fixed the problems and sent it back.

As of now the trans is in the truck and I'm prepping the engine for reinstall. I'll post back when it's all in to report the results. I've already put a stock pressure program back in so I can start over on tuning the trans. My wife is still having medical issues so my time on this is limited.

[Telco]

OK folks, I have a final fix on this. I sent the trans back to FLT, where they found that they had inadvertently installed a set of drag racing plates into the trans, which was making it shift so hard. My attempts to correct the problem through software resulted in trans pressure being so low that it wore out some of the innards. They put the correct plates in, and replaced the defective parts, total cost to me was shipping there and back. I now have a stock program in, lightly modified to suit my tastes, and I now have the trans I wanted to begin with. Each shift feels perfect. No slop, no bang. Loving it. I'd have posted this up sooner, but I wanted to give it time to make sure, and get the slippage problem the TC caused that I installed on my own with no input from FLT.

There was a slight delay in figuring this out though. When I got the trans back I installed a Hughes torque converter that according to my research should have given me a better feel and a higher stall than the one I had in there. What I ended up with was slippage code P1870, and a very sluggish vehicle. After discussions with FLT, I swapped the torque converter back to the one FLT sent. The slippage code went away, the acceleration is back and it's running better than ever.

Anyone wants a good trans by a company that backs up their product, even after a year, FLT (Finish Line Transmissions) (http://www.finishlinetrans.com/) is your shop.

[joecar]

Cool :cheers: thanks for the update.