TCC Modes?

[DrX]

Been logging my 80E. What is "AppEn" mode? i.e. what physical changes occur in the trans from "Off" to "AppEn" to "App" ?

Edit: I found the reference material posted by joecar: http://forum.efilive.com/showthread.php?4305-4L80E-Reference-Material
The chart below describes the apply sequence. I presume that AppEn is stage 1. Now my questions are;

1. Is there any situation where the PCM would only command stage 1 without proceeding to lockup?

2. Can this generate excess heat? It appears that there is neither apply nor release pressure on the TCC during this stage. (release pressure is removed)

* note this trans has been assembled to run full time high line pressure

[joecar]

AppEn is one of those in-between/transition states, usually the PCM would not stop there, it would either keep going or abort (if the load increases or misfires were detected).

There is not enough pressure yet to engage the TCC, so the TCC should not be dragging...

( the TCC apply circuit has its own pressure regulator so would/should not be affected by increasing line pressure (this is done to prevent converted ballooning), unless modified by builder )


if you suspect it is dragging then monitor TFT, TIS, TOS, TCCSLIP...

also monitor ATF color/condition.


You might want to set the Min TCC PWM table higher (and also set Max TCC PWM higher if not already).

[joecar]

Do you have any log files...?

[DrX]

I was looking at the AppEn feed (filtered 2-3 drive) to the TCC solenoid. At anything below around 45-50 MPH it just sat at AppEn and the temp kept climbing. After 20 min I was on a road where I could get the speed up a little higher and it was locked for about 10 min straight but did not cool down at all - it still climbed a couple more degrees. I think it was in the 230s when I pulled into the driveway. Will post the most recent log when I get home.

The trans builder recommended maxing out the PWM. i.e no PWM

[DrX]

Here is the log file.

[joecar]

230°F is bad... I would do whatever it takes to get TFT between 160°F-180°F.

What are you using as a cooler...?

ON/OFF is fine (you really won't mind the slight bump you feel).

[DrX]

I installed a new Tru Cool 40K cooler along with this trans. There is something in the tune or the trans that is causing the heat. I swapped out the converter and it made no difference.

The TCC engagement was the same before I disabled the PWM - just a quick bump. It did not want to hold over 30% throttle though.

[joecar]

From your log it looks like you get lock when throttle is steady at 20%(+/-few%)... when unsteady below this it sees to cycle between AppEn and Off.


Also, in your log, the TSTATE09-10 bit flags don't quite correlate to TCCDC% and TCCMODE...

did you swap in 4L80E segment (seems like it)...? if so it may not be quite all the way compatible with your PCM (what it seems to me).

[joecar]

That cooler is fairly large (about 1/2 the size of an engine coolant radiator), should get good quick cooling from that, even with the TCC unlocked, unless the TCC is dragging.

[joecar]

Something is keeping the PCM from locking the TCC all the way (keeping it at AppEn).

Something is causing the fluid to overheat.

AppEn is a 4L60E term... but it seems you're using a 4L80E segment... (see what I mentioned about compatible above).


sanity check:
- is your cooler mounted in airflow...?
- is it mounted with inlet/outlet at top or side (to avoid trapping air)...?
- did you verify fluid flowing thru the cooler (about 2 quarts in 20-30 seconds)...?
- are you seeing misfires...?
- is the TCC brake switch steady in the OFF position...?
- do you detect any problem with the converter does it seem too loose or too tight...?

[joecar]

In your log I see that when the TCC locks, TFT remains stable at 217°F... everywhere else it is increasing...

I'd say that the TCC not locking is causing TFT to run high... but a large cooler like you have should be taking care of it...

how is your cooler plumbed...?

[DrX]

I have redone the segment swap several times.

There definitely is some nonsense in the TSTATE data.

The temp still climbed another 5* during the 8 minute stretch where Locked and 0 slip were reported.

The cooler lines(-6 AN Teflon) are run directly to the Tru Cool.

[DrX]

I never got a trans hot warning with the previous 80E, but the direct clutches gave up after less than 1000 miles and the paint on the front of the converter was cooked. In that trans the pressure was under PCM control. The new one also has a T-brake.

[DrX]

Something is keeping the PCM from locking the TCC all the way (keeping it at AppEn).

Something is causing the fluid to overheat.

AppEn is a 4L60E term... but it seems you're using a 4L80E segment... (see what I mentioned about compatible above).


sanity check:
- is your cooler mounted in airflow...? stock cooler location
- is it mounted with inlet/outlet at top or side (to avoid trapping air)...? bottom as per instructions
- did you verify fluid flowing thru the cooler (about 2 quarts in 20-30 seconds)...? it was at least that much
- are you seeing misfires...? no see TSTATE data
- is the TCC brake switch steady in the OFF position...? yes see TSTATE data
- do you detect any problem with the converter does it seem too loose or too tight...? the converter that came with the trans was too loose (along with these other issues)and was sent back to check out. I have a different brand converter installed now, but have not tested its performance yet other than the tame test drive posted here. Same heat with both converters.

Seems that I may need to run a 60E tune with relay mod.

[joecar]

I never got a trans hot warning with the previous 80E, but the direct clutches gave up after less than 1000 miles and the paint on the front of the converter was cooked. In that trans the pressure was under PCM control. The new one also has a T-brake.Converter that shows signs of overheating usually means an internal converter problem.

[DrX]

Converter that shows signs of overheating usually means an internal converter problem.

But could it have been caused by the tune? It happened twice with that converter and I have never locked the TCC at WOT.

[joecar]

But could it have been caused by the tune? It happened twice with that converter and I have never locked the TCC at WOT.That is a hard question to answer...

if you can, try what you said, try the 4L60E segment with the harness mod and run the TCC from the 4L60E TCC ON/OFF signal.


Where did your tune file start from, and what has been done to it...?

[DrX]

That is a hard question to answer...

if you can, try what you said, try the 4L60E segment with the harness mod and run the TCC from the 4L60E TCC ON/OFF signal.


Where did your tune file start from, and what has been done to it...?

Stock tune > COS3 > 80E segment swap
It is an SD tune that is scaled 50%

[joecar]

I'm thinking you should have gone:

stock tune -> 4L80E segment swap -> COS3

you could still do that and copy in your scaled tables.

[DrX]

I'm thinking you should have gone:

stock tune -> 4L80E segment swap -> COS3


I was wondering if that could be an issue as well.

[DrX]

Well, I have rebuilt the entire tune on a fresh PCM with no change to the overheating issue. I do notice in the logs that the TCC slip is higher in AppEn mode than OFF mode. Not sure what is triggering AppEn when lockup speed has not yet been attained? There appears to be normal AppEn > App > Lock sequences after lockup speeds have been reached(in other log files).

The converter does lock, and very aggressively, when it is supposed to. The temp does still climb even during prolonged periods of TCC lockup.

You will also see a throttle blip at frame 5980 in this log .....should the slip not go to 0 at the converter stall speed of 2400-2600? The other converter behaved the same, so it is not likely a converter issue.

[joecar]

The slip rpm difference will not go to zero at/past stall/coupling speed...

the converter is fluid-coupling, but there still is a small speed difference, so the slip will be at its TCC-unlocked minimum...

and of course it should be zero with TCC locked.

[joecar]

Heads up, set these to in-range (not relevant to thread topic):



EFILive Custom Calibrations
{A0000} Forced Octane Scaler, was out of range when loaded.
{A0001} Forced Octane Scaler Percentage, was out of range when loaded.
{A0002} Octane Scaler Limiter, was out of range when loaded.


Trans parameters look ok to me...

[joecar]

Did you follow this (I know you did, but I'm sanity checking):


I'm thinking you should have gone:

stock tune -> 4L80E segment swap -> COS3

you could still do that and copy in your scaled tables.

[joecar]

Try setting D0409 to No Switch.

[joecar]

Just a hunch:

try setting the Throttle Kickdown tables to 100%...

try settinh=g the Shift Stablization Ratios to 2x or 3x their current value...

( I don't think this will lower temp in any way ).

[joecar]

Your log does not show TCC locking... post a log showing TCC locking for extended period.

[DrX]

The slip rpm difference will not go to zero at/past stall/coupling speed...

the converter is fluid-coupling, but there still is a small speed difference, so the slip will be at its TCC-unlocked minimum...

and of course it should be zero with TCC locked.

I should have said "toward" 0. The slip actually increases when the engine RPM is greater than the stall speed.


Heads up, set these to in-range (not relevant to thread topic):


Trans parameters look ok to me...


Not sure why those would show as out of range for you. It is not even possible for A0000 to be out of range (Enable/Disable). I did notice that sometimes when I compare 2 tunes some parameters that are identical show up in the differences list or an Enable might show as 255 for 1 tune and be considered different???

The trans tables are directly from a stock 80E cal except that I have removed the 2nd gear lockup over 90% throttle that is in the stock tunes.


Did you follow this (I know you did, but I'm sanity checking):

Yes.


Try setting D0409 to No Switch.

There is a switch but the factory setting is Class 2 Databus. I will try changing that setting.

[DrX]

Your log does not show TCC locking... post a log showing TCC locking for extended period.

Look at frames 5360 to 6660 in this log where the TCC is locked for over 2 minutes. The temp still increases another 14*. It never decreases.

[joecar]

...
Not sure why those would show as out of range for you. It is not even possible for A0000 to be out of range (Enable/Disable). I did notice that sometimes when I compare 2 tunes some parameters that are identical show up in the differences list or an Enable might show as 255 for 1 tune and be considered different???
...When I re-opened your tune file today, those were in-range, I don't understand what happened... hmmm.

[joecar]

Look at frames 5360 to 6660 in this log where the TCC is locked for over 2 minutes. The temp still increases another 14*. It never decreases.Hmmmm...

if the temp is increasing, then either of these is occurring:
- internal slipping (check TIS, TOS)(check fluid color/smell),
- pump is being over worked (line pressure is too high, check pressure at line tap on side of case),
- some bearing surface is binding (metal flakes in fluid),
- gearsets are binding or not lubed (fluid color/smell),
- fluid cooler is too small,
- fluid cooler is not getting air flow,
- fluid cooler is not getting fluid flow,
- fluid cooler has air trapped (e.g. B&M recommend placing cooler ports at side or top, not at bottom for this reason).

Do you know about the two different cooler line case fittings (I don't remember which is which)...?


But, that still does not explain the cases where the PCM is stuck at AppEn and is not going to Lock.

[DrX]

TIS/TOS look to be very close. 0 slip counts logged.
Cooler is new, 40K and mounted in stock cooler location. Cooling is not routed through the radiator.
There is plenty of fluid flow from the return line when disconnected from the trans.
I have even tried shortening the return fitting slightly as it was suggested in another thread I have on here that the fitting can sometimes be too far into the centre support and partially block that small hole. Although, the fitting measured identical to another one I have from a previous trans that was not overheating.

*Pressure is 210 and not under PCM control.

AppEn at speeds below the set apply speeds is odd and does seem to increase slip and hence create heat. The heat at full lock/0 slip seems to be a separate issue, but perhaps they are somehow related.

[joecar]

Or maybe the TFT sensor is reading wrong... can you point a laser temperature gun at the oil pan and see if TFT is close...

[joecar]

Hmmm, maybe they are two separate issues, or maybe related... (still scratching my head).

[DrX]

I haven't yet checked it with my temp gun. The pan did seem really hot though. Even if the sensor was off I would still expect it to plateau at some level.

[ScarabEpic22]

Even with a 40k cooler, you might not have enough cooling capacity. I know the TBSSs have trans overheating issues if you remove the factory radiator cooler, even with a big aftermarket cooler.

Can you try using DVTs to force the TCC to lockup and verify the TCC slip is at 0 (within a few RPMs)?

[DrX]

Even with a 40k cooler, you might not have enough cooling capacity. I know the TBSSs have trans overheating issues if you remove the factory radiator cooler, even with a big aftermarket cooler.

Can you try using DVTs to force the TCC to lockup and verify the TCC slip is at 0 (within a few RPMs)?

It will be a couple of days before I can do any more testing. I would expect that it will lock and go to 0 as in my logs. It does lockup at the correct speeds, other than the annoying release whenever the throttle decreases. The heat issue was present before I took the rad cooler out of the loop. It was not present with the previous 80E.

What I want to know is why does it goes to AppEn mode when no lockup is commanded. i.e. end of 1st, all of 2nd gear and 3rd below the calibrated lockup speeds

Does anyone have a normal 4L80E log showing the TCC mode, Gear, RPM, ETC TPS %?

[DrX]

I obtained a log file from another 80E truck and it appears that AppEn is the normal mode when unlocked from the 1-2 shift on up at any throttle over 16% or so. Unless the throttle % decreases, even the slightest, then the TCC goes to Off on the 80E.

[joecar]

Would you be able to post that log...?

So would you say that AppEn is not the cause of the overheating problem...?

Check the color/condition of the ATF now (after you done some driving), what does it smell/look like...?

[DrX]

It appears that the AppEN is normal and not directly related to the heat issue.

It was not an EFILive log. He supposedly has the same converter as I do, but his slip appears to be lower when unlocked(AppEn). Here is a screenshot where it is 2nd gear in AppEn mode. It goes to AppEn at the 1-2 shift as in my logs.

http://i114.photobucket.com/albums/n241/TDOC2004/TCC2_zps7103e49c.jpg (http://s114.photobucket.com/user/TDOC2004/media/TCC2_zps7103e49c.jpg.html)

The fluid seems OK for being to 250*. The drop on the left is from the dipstick. New fluid is on the right. Can't tell much diference in smell. Any particles were probably on the plastic lid I used for a background.

http://i114.photobucket.com/albums/n241/TDOC2004/IMG_59581024x781_zps1896c12a.jpg (http://s114.photobucket.com/user/TDOC2004/media/IMG_59581024x781_zps1896c12a.jpg.html)

Here is what I mean about the slip increasing rather than decreasing beyond the converter stall speed. It was the same with the other converter.(both are new) This did not happen with the previous trans.

http://i114.photobucket.com/albums/n241/TDOC2004/Slippaststall_zpsf546ecd7.png (http://s114.photobucket.com/user/TDOC2004/media/Slippaststall_zpsf546ecd7.png.html)

[joecar]

Is there a way of verifying that the TFT sensor reads the correct temperature...?

( point a laser thermometer gun at the pan and see how it compare to TFT )

[DrX]

Is there a way of verifying that the TFT sensor reads the correct temperature...?

( point a laser thermometer gun at the pan and see how it compare to TFT )

Bottom centre of pan 125 - 130*F, sides of pan over 2XX*, log 216*.

Held the transbrake to almost 3000 RPM and the slip was still climbing along with engine RPM - stall is supposed to be 2400 - 2600.

1sec throttle stab to 4800 RPM, slip went from 552 to 1150 RPM and increasing.

TCC responds normally to DVT

[DrX]

Temp remained steady at 216* while in Park for 5 min. Didn't drop at all though.

[DrX]

Swapped out the trans temp sensor to no avail. Tested the t-brake and the converter stalled at 2600 RPM as per spec, but also confirmed that the trans is trash. After that there was a lot of noise and the log showed 2nd gear only no matter what forward gear was selected. Tried downshifting to 1st at low speed and TIS went to 0 and the rear wheels locked up. Found what appears to be a 1/2" piece of steel wire on the pan magnet when I changed the sensor.

[ScarabEpic22]

Swapped out the trans temp sensor to no avail. Tested the t-brake and the converter stalled at 2600 RPM as per spec, but also confirmed that the trans is trash. After that there was a lot of noise and the log showed 2nd gear only no matter what forward gear was selected. Tried downshifting to 1st at low speed and TIS went to 0 and the rear wheels locked up. Found what appears to be a 1/2" piece of steel wire on the pan magnet when I changed the sensor.

Aw crap, not good to hear man. Might have been the clutches slipping even when they were engaged, slipping clutches = more heat.

[joecar]

Swapped out the trans temp sensor to no avail. Tested the t-brake and the converter stalled at 2600 RPM as per spec, but also confirmed that the trans is trash. After that there was a lot of noise and the log showed 2nd gear only no matter what forward gear was selected. Tried downshifting to 1st at low speed and TIS went to 0 and the rear wheels locked up. Found what appears to be a 1/2" piece of steel wire on the pan magnet when I changed the sensor.That's bad news, sounds like parts broke... :(

can you identify the piece of steel wire (is it straight or curly...?)...?

[DrX]

Click on the pics then click zoom a couple of times for full size.

http://i114.photobucket.com/albums/n241/TDOC2004/IMG_6120_zps71e0cd09.jpg (http://s114.photobucket.com/user/TDOC2004/media/IMG_6120_zps71e0cd09.jpg.html)

http://i114.photobucket.com/albums/n241/TDOC2004/IMG_6131_zps232e3a7a.jpg (http://s114.photobucket.com/user/TDOC2004/media/IMG_6131_zps232e3a7a.jpg.html)

[joecar]

I'm sorry, I thought I had replied a few months ago (but maybe I forgot to click OK)...

that is a very small diameter piece of wire (in comparison to the pan magnet), I looked thru my manuals trying to locate where it could be from, but I'm at a loss...

did you ever discover where it is from...?


does it look like wire (circular cross-section) or does it look like swarf...?
( since it has a wave shape and is steel (magnetic) I'm thinking it might be a broken off burr on the end of a clutch drum )

[DrX]

It looks more like it could be from a wire wheel/brush. The trans is still sitting here, so don't know what was causing the heat issue yet. The other issue I believe now was the trans brake engaging due to the PCM commanding a forced 1-2 upshift. It must have happened at exactly the same time as I hit the ratchet shifter to upshift....due to D0913 being an ignored parameter. Apparently the PCM is using an unavailable table and D0913 is switched off. I believe the 2nd gear only thing was due to the t-brake switch triggering a DTC.

No heat issue with the replacement trans. I have trouble getting it over 110*F cruising with the TCC unlocked. Hopefully, the D0913 issue did not hurt it too before I discovered this.

[joecar]

So replacement trans is running at cool temps :cheers:

(was the problem with the overheating trans ever discovered...?)

[DrX]

So replacement trans is running at cool temps :cheers:

(was the problem with the overheating trans ever discovered...?)


It has not been torn down yet, but it has already been back to the builder once for this issue. Took 6 months to get it back and it still had the same issue.

Possibilities? Full time 210 psi line pressure causing something to drag or diverting fluid from the cooling circuit? Mismatched parts causing a lube issue?...but this is an experienced builder. An internal blockage somewhere, or stuck valve?...would the trans shift properly in that case? I didn't log any internal slip. A problem with the trans brake?...I believe the new unit uses the same setup though.

[joecar]

Hmmm... could be internal leak in lube circuit, but then the gearsets would show blue coloring... hmmm.


Well, glad your latest trans is now good.