Trans problem

[YELTRK68]

My trans shifts to fast (1st to 3rd by 35mph), the fluid is full . I've tried to change the modulator still nothing. I've been told it could be the converter. If I hold it and shift it manually it...

[YELTRK68]

I meant to say it works fine when I shift it manually

[mr48chev]

What trans?
If it is a Turbo 350 the detent cable may be hooked up wrong on not hooked up.
The turbo 400 usually has the electric controls for the kickdown and when to shift on the gas pedal and that switch may not be working if you have a 400.

Also if it is a trans that originally came out of a car the governor may be set for a much higher gear ratio rear end and be causing it to shift sooner than you want.

[YELTRK68]

It's a 350 trans and I think the cable is hooked up but will check it tomorrow. The trans and 350 eng came out of a 78 camero. My truck had a 250 six in it with a 3 on the tree trans.

[Black-Dragon]

hey dad

[mr48chev]

Ok you have pretty much the same combo I have in my truck. I have a 350/350 that came out of a 79 Elcamino.

Check the adjustment on the detent cable or readjust it per instructions in a manual.

[68C15]

a bad vacuum modulator will cause early shifts.

[Longhorn Man]

YELTRK68... you have answers on the other thread that you posted ... the one of the exact same question.
Lets try not to double post, it wastes space, and gets confusing.

[KB71C10BBSUPER]

If you have replaced the vac mod on this, some are adjustable to control the shift pionts. If you pull the vac line off, look inside the vacuum port of the mod. if there is a slot where a small screwdriver will fit turn it clockwise one turn and test drive. This should delay the shift points. If not, it is possible the springs on the govenor are tired. That is a little differant job.

[KB71C10BBSUPER]

Sorry, if that is not enough continue one turn until desired shift point is acheived. If it is not adjustable then that is your first option to change.