Turbo 400 shifts too soon?

Pulling out of the driveway, it's in second gear before the front wheels are straight!

Can anyone give some advice?


Thanks!

 

Supposed to shift at 20 and 30 under normal acceleration, thats what the guy who rebuilt mine told me, and what mine does.

He also said it can only be the vacuum modulator or the governor causing shifting problems, I know there is a kit from B&M to change shifting speed using different governor weights, never tried it though

 

Is it possible that the th400 came from the factory behind a 6.2 diesel? Cause that would do it.

 

If you have an adjustable vacuum modulator, screw the adjusting screw, in the ******, in to delay the upshift. If when you pull the vacuum hose off and ATF runs out, replace the modulator with a new one. You also need 12V on the terminal on the left side for WOT upshifts beyond 3600 rpm. The voltage is applied at 3/4 throttle and above.

 

If it is from behind a diesel, that's ok. You would just need to change the governor to a gas one. They are pretty cheap, and some transmission shops might even give you one.

Governors can be tuned with weights and springs, a-la the B&M kit, and others.