Thread: P0742 after fluid and filter change.

Originally Posted by QUICKSILVER462

What you are seeing with the car in the air and one wheel turning and the other one not turning is normal for an "open" or "non-posi" differential, which is why these cars have traction control.

Just got off the phone with the shop, and they told me the same thing, that these cars hve an open differential, so that was normal. I was actually just forum searching to confirm this, and it found my post with your reply. Thanks for the info though, I appreciate the confirmation.

Took it to the transmission shop, the managed to get the max adapt long shift code to pop up in addition to the tcc stuck on code. Final verdict was to go ahead with a rebuild. The car has 160k on it, the logical part of me thinks I'm an idiot for doing the rebuild, but we do love these cars don't we?

Should be picking the car up today, shop said the tcc oscillation, the rpm jumping up and down, was a computer problem on these 97 to 01 models. That it caused the convertor to pulsate in and out of lockup really fast, eventually leading to premature wear. He said the GM service manuals say that there are a couple things they can do, but the ultimate solution is to reset the computer. He said doing this usually works for about a year, then has to be redone. Anyone got any comment on this?

Got the car back today, replaced the torque convertor, tcc, epc, put in a hardened 4th clutch hub. Total was 1772 and some change. I think I made out ok, but time will tell. Especially since I'm about to make a 700+ mile trip tomorrow.