4l80e tuning

[gpr]

I finally finished up the installation of a 4l80e and a 3600 revmax stage 5 converter. In the tune I changed the gear ratios for the transmissions, and also increased line pressures by 10%. I also decreased shift times to around .300 seconds. Then I took off all the torque reduction management. I also left the mph that the converter would lock up, so it would drive like the old 4l60e.

On the first test drive I was surprised it didn’t shift harder. Felt a little slow and soft to me. Do I need to increase line pressure more? Or what else can I do to make it shift quicker?

Also the converter was not locking up when it should. Cruising down the road it only locked up once or twice. Is there something else I need to change to get the converter to lock up? Also it seems like it locks up very aggressively. When it did lock it felt like the car shift it kicked in so hard.

BTW, to get the tranny to work in the car I am using a pcm4less wire harness. Which is suppose to allow me to use my existing tune to control the 4l80e.

[joecar]

Reduce the shift times to 0.2s.

Try increasing shift pressure some more (say 25%).

Also, make sure that the PT up/down shift tables make sense

(as you place the cursor over a cell containing MPH, the bottom of the tunetool window shows rpms for all gears, look at the rpm for the gear of the table you're in)


Also make sure the VE and MAF tables are correct.

[joecar]

What PCM signal are you using to lock the TCC...?

Was the PCM originally programmed for a 4L60E...? And this PCM now has the 4L80E segment swapped into it...?

[gpr]

Here is my tune if you would like to check it out. The pcm is programmed for a 4l60e, and with this harness is suppose to control the 4l80e. It seems as if it is working but just isn't locking up the converter when it should. There is no segment swap.

Do i need to do anything about the pressures of the torque converter? I thought i read one time too about you need to modify the PWM when running an aftermarket converter.

[gpr]

I ran this log this morning, if you'd like to check it out. I think i might have a mechanical issue with the converter itself. Today driving while logging i never got the hard hit like i did the other day of the converter locking, however in the log the TCCMODE is showing locked. In the log several times you can see where i would give it gas, engine rpms would increase but mph never increased accordingly.

I will call rev max about this, but the convert is being commanded to be locked up it just isn't. You don't see anything in my tune that could prevent it do you?

thanks for the help

[joecar]

If the PCM is programmed with the 4L60E segment, then take note that the TCC PWM signal cannot be used to drive the TCC PWM solenoid in the 4L80E... you have to use the TCC On/Off signal instead, or use a relay to gate TCC PWM from TCC on/off

[ reason: the 4L60E controller spikes TCC PWM while TCC On/Off is off ]


If the PCM is programmed with the 4L80E segment, yes you can use the TCC PWM signal to drive the TCC PWM solenoid in the 4L80E... but you have to make sure that the pinout at the transmission plug is modified from the 4L60E pinout (TCC PWM is on a different pin).

[joecar]

In your tune you might bump up the min TCC pressure (TCCMODE says it is locked, so maybe it is slipping)...

make max TCC pressure say 99%, make min TCC pressure say 90%.

[joecar]

BTW: the pids TCCP, TLPCC GEARCOM, PRNL are not for the 4L60E/4L80E.

[Wolfie]

This is one of the sections I regularly read, and it's nice to see joecar is still at it!!!!!!

[gpr]

If the PCM is programmed with the 4L60E segment, then take note that the TCC PWM signal cannot be used to drive the TCC PWM solenoid in the 4L80E... you have to use the TCC On/Off signal instead, or use a relay to gate TCC PWM from TCC on/off

[ reason: the 4L60E controller spikes TCC PWM while TCC On/Off is off ]


If the PCM is programmed with the 4L80E segment, yes you can use the TCC PWM signal to drive the TCC PWM solenoid in the 4L80E... but you have to make sure that the pinout at the transmission plug is modified from the 4L60E pinout (TCC PWM is on a different pin).

I am trying to get a hold of them to get the wire diagram. However, when i bought it they said you did not need to change anything in the tune to control the 4l80e, also the wire harness has some relays on it. I'm assuming these are so you can do like you said and drive the TCC PWM in the 4l80e with a 4l60e tune....

I'm changed the max TCC pressure to 99 and min to 90 like you said and will give that a try and hopefully the converter will lock up now. It is strange the first time i took it out, I did get it to lock up once or twice but now it wont. Could this indicate something else is wrong with the converter or tranny???

[gpr]

This is one of the sections I regularly read, and it's nice to see joecar is still at it!!!!!!

I agree 100% on that. Pretty sure if it wasn't for joecar my vehicles would not run!!!! Can't thank him enough for all the help he has given me, but even all his post on almost all topics to help everyone learn.

[joecar]

Thanks guys... lol, I have to breathe car every day in order to live :cheers:

[joecar]

...
Could this indicate something else is wrong with the converter or tranny???Not necessarily...

if you have a passenger you could command the TCC locked by doing this:
- in manual 3rd, get sufficient speed in 3rd gear,
- goto DVT tab, select LS1B controller, goto Auto Trans tab, click Activate,
- for your year's TCC, click Turn On and 100%DC (both buttons),

TCCMODE should show lock, rpm should not move much as you partway increase throttle (feels like a manual trans car)...

with throttle partway open steady, push on brake pedal, rpm should increase by a few hundred (as little as 100).

[joecar]

Sanity check:

check that each TCC release curve is at least a few mph below the respective TCC apply curve


( I looked thru those in your file, but I am known to need a sanity check :) )

[gpr]

Well i believe it is now locking up properly. I was playing with it and locking and unlocking it from the DVT tab. that is a very handy feature!

One thing i was logging is the "last shift time" to see how quick it was really shifting as i thought it seemed slow. If you look in the attached log towards the end there is a point where i did a wide open run. the shift times from first to second show 1.2 seconds, then 2-3 shift at 1.3 seconds. It shows it is in seconds, but that couldn't be right. still seems a bit slow. I will have to do more playing with it and maybe bump up the base pressures some more.

[Chevy366]

I agree 100% on that. Pretty sure if it wasn't for joecar my vehicles would not run!!!! Can't thank him enough for all the help he has given me, but even all his post on almost all topics to help everyone learn.

Yeah I would like to meet joecar in person, he must be like one of those bobbleheaded dolls (no disrespect intended), his head ten times larger than his body from all the knowledge he has stored there. :good: