I got a t350 in a 84 cutlass supreme. My problem is that it only shifts from 1st to 2nd gear only and hard. When it does shift its @ about 25 mph. What can be the problem?

 

Is there a vacuum line from the manifold to the transmission vacuum modulator check this out it is like a booster for the tranny when mine was not on my th400 it ran 3500 rpm in first.

 

It would help to know that type of trans it is (TH350, TH200, 200-4R). As noted, if it's a TH350 with vacuum modulator, either the modulator is bad or the vac hose has come off. If it's a trans with a throttle valve cable, the cable is probably not adjusted properly.

 

Thanks guys but i couldnt find the vaccum modulator. i did find the throttle valve cable, how do i adjust it properly?