66' impala 4l60e silverado tune. transmission COOKING

[ari666]

hi all. i have a 66' impala, 7.4ltr gen 6 454, holden commodore 2001 ecu (0411) running a modified chevy express tune.

the trans COOKS after a few minutes and ive run out of ideas why. the first time it did it was on the dyno. i limped it home to a friends house. he drove it a few times and it lost reverse so i had it completely rebuild with the usual upgrades. i thought it was fixed, so flew 5400kms from broome to melbourne to drive it back and it still cooks.

please please can someone look at my tune and tell my where im going wrong?

the trans is completely rebuilt
ive rechecked my wiring to the plug. its all correct.

i was deeeearly hoping to drive this lady back to broome.

thanks in advance






07-03-17 CHANGED TRANS.hpt

[ari666]

what seems weird is that watching the TCC apply, itll be off when cruising then comes on whenever throttle is applied.

also if you put it in neutral at the top of a hill, it refuses to roll.... its like a clutch pack is engaged or something.

kinda feels like it wants to kick down a gear every time you lift off tps too. id get a log file but i dont want to damage my brand new trans any further than it has been already. we ventured up into the 260F mark today

[ari666]

im noticing that if i force the gears, 2nd gear has A as "on" and B as "off" and 4th as A-off and B-on. everything i read online says this is opposite to what it sould be, but when i command 1-2 or 2-3 on/off they respond as normal..

.also i cant seem to command the 3-2 solenoid on.

[ari666]

this is an old NON-pwm TCC trans running off a PWM pcm

[ari666]

i switched the A and B wires to the two solenoids and it felt like it was trying to start in 4th, so put it back to the way it was.

anyway, before i did that, took it around the block and got this log file.


quick block.hpl


man, im reeeeeally hoping someone out there can say "you silly man, turn this up and turn that off and itll be fine" because i really had hoped to drive this back home.

[Fast4.7]

hi all. i have a 66' impala, 7.4ltr gen 6 454, holden commodore 2001 ecu (0411) running a modified chevy express tune.

the trans COOKS after a few minutes and ive run out of ideas why. the first time it did it was on the dyno. i limped it home to a friends house. he drove it a few times and it lost reverse so i had it completely rebuild with the usual upgrades. i thought it was fixed, so flew 5400kms from broome to melbourne to drive it back and it still cooks.

please please can someone look at my tune and tell my where im going wrong?

the trans is completely rebuilt
ive rechecked my wiring to the plug. its all correct.

i was deeeearly hoping to drive this lady back to broome.

thanks in advance






07-03-17 CHANGED TRANS.hpt

Really do not think you will ever get a 4L60E to last behind the big block. I could not get one to last behind my 350 in my Express van. Killed the factory trans in 38K and had a well built 4L65E that lasted less than 40K. That being said the Express vans came with both the 4L60E and 4L80E. Almost sounds like you have a 4L80E tune in the PCM. The 4L80E does not use a 3-2 solenoid.

[ari666]

CLOSED THROTTLE PRESSURE!!!!!!

ha ha!! for some reason my closed throttle pressure tables were all zeroed out!!!! i figure this meant that when tps was lower that 2% the pressures went to zero and the trans was trying to go into reverse, which is why it burned out reverse the first time!!

its only a partial step forward though. trans temps are FAR lower than they were before, trans shifts really nicely, but those trans temps slowly are creeping up got to 240F before i stopped it today. ill drop the tune file i have here again. same file name but upgraded tables. can someone have a quick look and see if anything is outstandingly wrong?

ive changed the pan filter and flushed new fluid in. got a trans cooler with nice airflow through the rad via the thermos, fluid goes through both radiator and cooler.

cheers muchly

07-03-17 CHANGED TRANS.hpt

[ari666]

Really do not think you will ever get a 4L60E to last behind the big block.

theyre behind silverados and last ok. the impala is about half that weight, isnt 4x4 and isnt a wild build at all. 230RWKW making most of its power at 2000 rpm, dies at 4500

Almost sounds like you have a 4L80E tune in the PCM. The 4L80E does not use a 3-2 solenoid.

that may be very likely. i couldnt seem to get any signal for 3-2 on/off with my multimeter off the PCM on command. ill have a dig tomorrow to see what the affects of a loss of 3-2 are. the only thing is that in the transmission section under"general" the option for 4l60e is there.

still food for thought. appreciate the suggestion.

Ari

[ari666]

if anyone stumbles on this thread with a similar issue, the solution was a segment swap. i shouldve paid more attention to this comment:

Almost sounds like you have a 4L80E tune in the PCM. The 4L80E does not use a 3-2 solenoid.

the tune i was running was indeed a 4l80 tune. i stupidly thought that the dropdown menu that "changed" trans type to 4l60e actually did something. it doesnt. doesnt do a dang thing. the wiring on the 4l80 and 4l60 are different by 3 wires, TCC PWM, TCC lock and 3-2 shift. so while i was driving along happily, the TCC command would open 3-2 shift.

a segment swap changed the pinouts of the PCM and thus i suddenly regained control of 3-2 manually via the I/O function on scanner.

the damage? well i lost 3rd gear after about 3,000 kms, but otherwise everything works great now. nearly 8000kms later the impala is safely in its new home.