Strange T/C Activity
About a year or so ago, I noticed the torque converter locking and unlocking at weird times. I can feel it lock when driving, usually after shifting into 3rd. It feels like another shift, but isn't. It then doesn't unlock until the truck almost stops, which bogs it down considerably. If I stab it while at a slower roll, the TC engages pretty violently and the truck lurches forward. I figured the TC was going out, so I drove it for a year waiting for it to totally stop moving. It never really got worse, but I figured I would replace it anyway. The trans has over 150k on a stock rebuild, and with the extra power (38R, single shots, etc), figured it was about due as well. So we spent a couple days swapping the TC with a new billet triple disc unit and a performance rebuilt 4R100. Anyway the truck drives identical to how it did with the old trans and TC. Same weird TC behavior. Any ideas on this? It just started doing it one day about a year ago, which made me think it was a mechanical issue, and I have a very hard time believing that the new parts act the same as what just came out. It was an expensive trial that didn't help a thing. Although it now has a trans that should hold up to the extra power and not have to worry about it any longer.
Any thoughts would be great. Thanks.