th400 problem...?????????

[kelseydum]

I have been noticing a problem. At first it was bad and I did some work on the tranny (new gaskets and seals to stop some leaks) but I also got a new vacuum modulator. I'm not sure as to how to set it except I believe turning the pin clockwise makes it shift later and counter-clockwise... earlier. If this is backwards let me know.

Anyways, my problem is when I slow down it seems to be shifting sparatically back and forth between 1st and 2nd. When I go up a hill or even on a straight away when it hits second gear it kind of boggs out or stalls. It REALLY seems as though it it shifting into second gear too soon.

If it shifts to second gear too soon and the rpms are too low will it cause this bogg down or stall? should I try adjusting the modulator more before I assume the gear is burnt out?

 

[LOWANDRATY]

turbo 400 problems

If 2nd was burnt up, meaning the clutch drum or band was bad it would slip, not stall out or bogg, try shifting it manual, start in low then when you think it needs to shift move it to 2nd, see what happens, if it all works out ok then adjust the valve some more to make it shift longer and harder, the transmission should have band adjustments on the side. dont mess with those untill your sure its not just an adjustment with the modulator valve, turning in or clockwise will increase the amount of pressure on the valve, and will cause longer shift points, and harder shifts.

 

[kelseydum]

Thanks man. I'll try that. I mainly wanted to confirm which direction does what on the modulator. I thought I might have had it backwards.

 

[sneakysnake]

I had the vac line come loose on me one time and it wouldnt shift out of 1st until it was rapped out, sounds like your modulators not set properly.