Last year my transmission went out on me so we rebuilt it with performance parts, and put a 3000 Stall Converter in. It all works beautifully except from day 1 the Torque Converter Lockup Doesn't seem to work, and today it REALLY pissed me off so I decided to post about it and see what I can do about it.

Today I was on the freeway for a 35-40 mile trip. If it was in Cruise control, the RPM's would be hovering back n forth constantly between 2500 and 3000. Without Cruise I could keep it a little closer to 2500. But It really didn't matter what speed I was going, the RPM would be that high. 60mph 3000RPM, 85mph 3000 RPM. Deffinatly doesn't seem to be lockin.

What would be the easiest way to test it out? Also, I remember that it is just part of the wiring harness inside the tranny, do replacements just splice into current wiring or do ya gotta replace harness with it? Is there some trick to seating it down that I missed? It's bolted down in place but maybe I got it wrong. Can I test it with a Volt Meter?

I used to get 280-300 miles per tank, now it's just BARELY 200mpt

 

Does the converter lock up intermittently or just never locks up? The easiest thing to try first is see if the PCM is telling the converter to lock or not. Then you will know if it is a tranny issue or another issue. If you have access, or can get access to a scanner like a Tech2, they can be used to command the converter to lock up while driving for testing reasons. I'm pretty sure all GM dealerships with a large shop use them, as well as some smaller privately owned shop, a good tranny shop may have a similar device.

While driving the scanner can command the converter to lock up and if it does every time you know where to start looking.

See my posts in these threads about the TCC issues. I chased my problem for over a year until I found a solution which I explained my the 2nd link below. That problem may not apply to you but could point you in the right direction.

https://www.camaroz28.com/forums/sho...d.php?t=660885

https://www.camaroz28.com/forums/sho...d.php?t=659224

 

I wish I could get a scanner It's a 95 with check engine light on for the longest time because I don't have access to anything that'll read a stupid 95. I'm sure it's physically related to the lockup, there were no complaints with it before we rebuilt the transmission and now it doesn't at all. I was talking to a friend about the issue and he was saying that his Duramax 2500 refuses to lock up in the morning now that he lives in detroit and it's -13 or so a lot. But I really don't think it's temperature related, it was doing this through summer and winter

 

Find the TAN wire WITH the Black STRIPE in the harness going to the trans, Hook a 12v led to that wire and the other end to 12v in car, drive car if converter is being comanded to lockup the led wil come on if not the command is not being given .
When the unit was rebuilt do you emember if there was a little gren oring installed on the end of the input shaft ?

 

Green O Ring on the end of the input shaft as in inside the Torque Converter? I believe so but It's been since May when we did it. I really like the Idea of the LED, would be nice to mount one somewhere. I like knowing when it's in once I get it workin. I doubt it would effect it but we also removed the + retainer and Checkball in the end of the input shaft to engage lockup a bit harder than stock as well

 

No the oring is on the end of the input shaft
And yes we remove that check ball on every unit we build

 

Good to know it's reccomended to do that I'll look into puttin teh indicator light, sounds great Thanks.