He says still waiting on word from the dealer. So still playing the middleman I'm guessing.

 

Neither do I. Definitely not on a 98-02 F-body

OP - I understand your frustration here. This was probably a wiring issue from the start. This "tech" didn't do any type of troubleshooting from the sound of it. Now that it has a "new" trans and is throwing an 1870 code, which is excessive slip of the TCC, sounds like he messed up the force motor adjustment too. If the TCC doesn't get enough line pressure to lock, then it simply doesn't lock. This is actually a mechanical adjustment on a lot of transmissions. The tune can change it too, but only based on the settings of the force motor.

The code is telling you the TCC is slipping beyond the limits set in the PCM. Normally this is an expected fault when changing out a TCC to a higher stall, like 3k and up. Obviously it will slip more than the stock settings, so this code is simply tuned out for the most part most of the time.

My guess is it would have been a problem with your TCC PWM pressure wire (pin u), and/or the 1-2 shift solenoid (pin a). Really rookie stuff that could have been checked with a volt meter.

Normally when a 4L60 breaks, it breaks. You will completely lose gears, be left with one working solenoid, or nothing. I've went though 5 4L60's before finally pulling the trigger on a built 4L80.

This dude is a disgrace for everything he put you through through parts at it. It's cool he knows how to rebuild transmissions, but sad to think he can't figure out a wiring problem and simply assume they are good. That and have the ability to "flash" a PCM but no ability to diagnose an issue or test it with a scanner? Or check the trans pressure even? Not his money I guess. Sorry for your ordeal.

 

Update: after more than a month I finally picked up the car this morning at the dealership and instead of paying the $750 I only ended up paying around 400 for a new ECM which ended up being the culprit. Thank God this is over, it was by far the worst experience I have ever had with a mechanic and a huge weight has been lifted off of my shoulders. After I got it home it was filthy and I decided to give it a nice 5 hour detail to welcome it back home. Thanks for all of your guy's input really appreciate it.

 

**** happens and it sound like the mechanic took a loss on the deal, He's probably not happy about it either. At least he kept his word and took care of it.