Arising "New" Transmission Issue

[RetroJohnny]

Hey everyone, long time since I've been on here, been real busy with work and what not. But I've done a lot to my Reatta, new front supension including struts and mounts, and it really is turning out into a perfect little roadster except one underlying issue. My Reatta has always had rough shifts here and there, but lately its been completely absent and shifting great. Up until today... After driving 70 + on the interstate for 20 or 30 miles, back on a smaller highway all of a sudden the transmission suddenly started freaking out. I say this because once I hit about 45-50 MPH it would be constant slipping and failure to upshift. Just terrible abrasive jolts. It would not allow me to exceed 50MPH. So we drove it straight home and I checked the fluid and it's right on par. There are some air bubbles in the fluid though (leak possibly?) but there are never puddles in the garage, and my Reatta has put 500 or so miles on it in the past month. So this is a new issue for me, and I was wondering if any of you know where I could start looking to pinpoint this issue... Hopefully not a new transmission ? Thanks!

[RetroJohnny]

Thank you so much, I am actually planning on looking into the TCC Solenoid, heard they aren't too hard to replace. But also everytime it rough shifted the CRT would read "Electrical Problem has Occured, Sericve Soon." So my guess it has to be elecrical if the computer is aware of it.

[RetroJohnny]

Yes, I have checked the codes, the only code I found was E039, which the Reatta Service Manual reads "TCC Circuit" , So hey, maybe it is that simple of a fix. And I couldn't be the ignition coil or ICM, those were replaced not two months ago becuase I had exactly your problem, sticky gooey stuff coming out of it. But exactly your thought, the TCC is what the computer thinks it is, so that is going to be my first fix! I checked and they are about twenty dollars on RockAuto.

[Ronnie]

See if you can find DeoxIT in  your area. It works miracles on cleaning low voltage connections like on the transmission. I use the liquid in a small tube. I have to order it from Amazon. I've not found it around here. I guess the spray would be good too.

[padgett]

Any time a GM automagic acts up I drop in a can of Seafoam Transtune and drive a bit. valves tend to get sticky over time and this cleans them out. Mostly.