Locked up TC, Fwd, Rev, all gears.

[buzzinghalfdozen24]

So, to make a long story short, driving home tonight my TC isn't unlocking. Tried all scenarios, and same result. Shut truck off, restarted, same result. In fwd or rev, it lugs super super low, and then upon shifting to neutral, it revs up to 14-1500 or so, as if it's clearing its throat. Same in fwd or rev. My research is telling me that it's most likely a TC failure, with a small possibility of a TCC solenoid being stuck from debris. Ideas?

Transmission history. Full rebuild about 60k ago. New bands, clutches, servos, 3D TC, etc. been flawless since. I did a flush about 40k ago. All clean oil. Perfect shape, perfect shifting. Till now anyway.

i understand everything can fail at any point. But am having a hard time believing that a good 3D TC would fail after ~~60k miles. Especially with no abuse. I don't truck pull, rarely pull trailers, heck I rarely even drive it hard enough to smoke, haha. I'm hoping some guys will chime in a say there is lots of problems with the TCC solenoid, or another solenoid on the valve body. Really don't want to afford a new TC or a built truck, haha.

I left on trip in a car for holidays, so trying to troubleshoot from my computer while gone. Thanks!

 

[Motorhead]

I think that you would be best served to have a good knowledgeable transmission mechanic put a real time scanner on the truck and see if the lock up mode is on command or not when the converter is locked.
You might try disconnecting BOTH battery grounds for 10 minutes and then re-connecting them to see if that clears the issue.

 

[cerberusiam]

As a rule, if you have FOD in the circuit it is blocking the apply and they want to slip or lockup slow, it almost has to come in from the pressure side not the release side of the circuit. The other issue is the pump cover warping and dragging the clutch, that usually is due to a bad TC or just bad assembly. It should show sooner than 60k or after a trauma to the drive line but that is not an absolute. The fact it is a triple bears some though as far as warped pump cover but it just as well could be cheap design. Too many triple converters simple do not put any help into the real issue sin the TC they only try to stop slipping. Not all TC's are equal and depending on the cost you can pretty much tell how well engineered and built they are.

The sprag failing will have some pretty definite symptoms driving. It will want to pull thru the brakes at a stop, the throttle will feel dead until you get past 30-35 mph then it feels normal. It will shift into and out of OD without issue, you feel the lockup in D and OD firmly apply, etc. The problems start once you stop and try to accelerate. The other 2 failures will almost always impact shifting and lockup feel.