>From Allen Puma >I just had my 68 TH400 OG tranny rebuilt in my 68 442. I will be bringing >it back to AAMCO That was your first mistake!!!
> If I am cruising at 50 and hit the kick down, the engine >seems to race freely in 2nd gear and the car seems to not accelerate much. >As I let up my foot the tranny drops into 3rd and pulls nicely. The same >thing will happen at 20, but from 2nd to first. >On another note the >fellow at AAMCO said that the center support was the old style and he >changed it to the new style. The teeth on the new one were not as tall. >He said the center support from my 68 was used in plow trucks. Anyway, does >anyone think the original center support is better, and does it sound like >the tranny is slipping? I hope to get the car back in next week. Thanks. I wouldn't be anywhere near as king to the dumba$$ at ammco. You can't just go swapping center supports willy nilly. The center support from late '69 back has lugs that are about .040" longer than the lugs on later center supports. The later supports have a ring installed behind them which helps protect the soft Al of the case, and that was the reason to shorten the lugs. Additionally, the later supports use chincy (sp?) plastic parts for the apply piston. The symptoms you are describing could very well be caused by those missing 40 mils, allowing the center support to be too far back and preventing the clutch which it serves as the apply piston for from applying properly. I hope that no damage to the tranny case has occurred. As an aside, the ring which I mentioned seems to have been shipped from GM already installed in replacement TH-400 cases and is no longer available anywhere. Not that it ever was available on its own. Jim I think I rebuilt my 69 OG properly, but still need to get the body back on the frame to see.......
