wogs73

What would cause a turbo400 to disengage when I let up on the throttle? Other than that everything works fine. It's like it goes into neutral and then has to catch up when I accelerate.

Thanks :confused:

lyonsh

It could be a hydraulic problem (sticking valve), or it could be worn clutch packs.

Or it could be something else. I'm not an auto trans expert by any means, but I've seen these two things cause similar problems.

BB73Chris

Would a high stall torque converter act like that?

arrio76

Does it upshift at normal speeds? Is your issue with the trans happening in 3rd gear or lower gears? Need a bit more to go on.
Initially it sounds like a late upshift problem. Could be leaky vacuum to the modulator or defective modulator. Also could be the govenor or shift valves sticking.



[Modified by arrio76, 11:54 AM 4/17/2004]

wogs73

It only happens in third gear. It shifts fine under all circumstances just disengages in third under light throttle.

mandm1200

I can't help you with your problem but I can give some advice. I had a work van that did the same thing except it did it in 2nd gear. The van was always loaded and weighed about 7500 lbs. so downshifting into second was a necessity at times. Called a local GM-Chevy garage and they said to bring it in and they would change the screen and fluid. I didn't think that would fix the problem, but I knew they should know more than me. I was quite disappointed when I got it back with the same problem. The only difference was my wallet was $100 lighter.