ok, i have a 96 lumina with the 3.1 and the 4T60E transmission and 213300 miles. The issue is that when on the highway, occasionally overdrive will slip for a second and throw a P1870 SES code. i was looking at possibly doing a rebuild on the transmission. i found an ebay kit here: ebay rebuild kit and was wondering how feasible this is as the motor still runs great and the body is still in good shape. Thanks in advance

 

I'm in a similar 'boat', I have a 1997 Lumina 3100 (Vin M) and have a decent amount of slipping between shifts, and no shifting (stuck between gears/N) when the transmission is cold (any weather below 40*F, if engine is cold start). I've read the my problem is mostly related to solenoids on the valve body, but have still wanted to do a full rebuild, while working out the other issues. Anyone have any information on doing a rebuild? Some publisher would be well-off to publish 4T60-E service books, plenty of us with info needed from such a source.