BuckNasty92

Bump

I figured I'd try a few more things before I spend $800 in parts to try and fix this. I'm not a "Throw parts at it until it works" kind of guy lol

I did OHM the wire from the trans connector to the PCM and it Ohm'd at 67 to 70. That doesn't seem very normal to me but I've read that it can be normal to find that in some circuits of a vehicle. Sorry if that seems kinda brain dead obvious if it is an issue, I'm not very good with the Ohm stuff.

I'm also running a 12202088 OS on a 0411 which seems to be a not as common OS to do the 4L80e swap on. I had to email HPTuners for a segment swap file the matched my OS and had a 4L80 from factory. I'm wondering if this is a case where a segment swap didn't take.

Dropped the pan and put in a new TCC PWM Solenoid today and checked my dipstick fluid level mark. It was way too low so I made a new mark and adjusted the fluid level up to the correct level. Drove the truck around the block to, once again no changes even when forcing the PWM control with 100% duty cycle granted I wasn't going but 45mph in 3rd but it should still lock up when manually commanded. There was one weird change: I couldn't manually command gears using the shifter but I could command them via the hptuners controls. Not sure if it was something with my tune. The fact that the converter has locked up two or three times before when I first got the swap running has me all confused. I'll repost my current tune here and hopefully figure something out. Was planning to take the truck on a trip soon but this has to be figured out before I'm comfortable taking that long of a trip.

BuckNasty92

Well for future readers and if anyone comes across this post while searching, I did find my fix. It was my valve body and more specifically, the TCC valve and bore. I ordered a remanufactured valve body off ebay that had the Sonnax TCC valve and bore redone as well as some other upgraded parts. Changed it over and the thing locks up at cruise and drives like a dream so far. Looking at all the factors (age, 170k miles on trans, pcm commanding at correct times) it makes sense now that this would be worn since it is a common issue with the 80e's.

Can't wait to order my converter and cruise this thing now

madmann26

iTrader: (7)

Excellent!!! And thanks for the follow up!!!

Drspencer

iTrader: (1)

Holy crap. I wonder if this is the issue with mine. Granted, I gave up and put my 60 back in since I was leaving for a year. But....I have a feeling I'll have to put the 80 back in with the amount of towing I do. Thanks for all the hard work on this, just one more thing for me to look at with mine.

https://www.performancetrucks.net/fo...towing-553197/

BuckNasty92

No problem. I’m an investigative guy because I know this won’t be the last truck I build so I’m always happy to do the leg work and post it so people don’t pull their hair out like me. I wasn’t about to put my 60 back in either lol. I got too much of a tease to a good power holding transmission so I had to persist. I read your thread you linked in your reply and it does sound similar to what I was dealing with although mine was a complete loss of lock up due to a worn valve body bore. After the valve body swap it holds just fine. In fact a week after I got it back together I drove it 8 hours to Colorado Springs, all over the area for a week, up and down Pikes Peak then drove it another 8 hours back home doing a few highway pulls with some randoms wanting to run em. Needless to say I’m very pleased with the outcome and hopefully you can find some resolution as well. I’ll keep an eye on your other thread.

Drspencer

iTrader: (1)

What vendor on eBay did you get the VB from?

BuckNasty92

I think it came from Central Valve Bodies. It’s nothing special. I still had to put an HD2 Kit in mine before it went back in