Shift prob after rebuild(1st gear not working in "drive)

[Russell Keys]

Shift prob after rebuild(1st gear not working in \"drive)

I recently rebuilt the th350 in my blazer. It pulls much bettter than before but when I put it in drive it always starts in 2nd. Then shifts to 3rd normally. But when i put it in manual low it starts in 1st fine but when shifted into 2nd it stays in 1st until I shift it into drive. Then it shifts fine but seems to skip 2nd. I was confident in the rebuild until now. Does anyone have any ideas or suggestions on what I can check or adjustments I can make? Any help will be appreciated.-Russell

 

[FWP]

Re: Shift prob after rebuild(1st gear not working in \"drive)

Just a guess, but to me, sounds like a a sticking valve in the valve body. If you haven't, check the usual- linkages, vacuum hose, kickdown, etc.... Next drop the valve body, and see if all the pistons slide on their own. Maybe something stuck there, like the 1-2 valve. HTH

 

[Russell Keys]

Re: Shift prob after rebuild(1st gear not working in \"drive)

Yeah I was leaning toward the valve body too. I just didn't want to have to drop it. I talked to two shops today and they said the same thing. It looks like it's gonna be fun to put that thing back in. Thanks-Russell

 

[NoSmog73]

Re: Shift prob after rebuild(1st gear not working in \"drive)

You might want to try trans-x. It does work pretty good it is said to lube the stick valve's

 

[Ryan B.]

Re: Shift prob after rebuild(1st gear not working in \"drive)

I agree with FWP...
After checking the linkage, vacuum line to the modulator, kickdown cable....
Sounds like the sticking 1-2 valve in the valve body is a good theory.

One thing i might add is when dropping the valve body out with the tranny in the vehicle...
...when all the check balls fall out, its hard to keep track of where they went...
If you can remember where they went otherwise look in the rebuild manual for the locations of the checkballs...
I used transmission assembly lube (grease) to hold the checkballs in the proper cavity while re- installing the vavle body. Makes it 100 times easier when those checkballs are already held in place with grease!
I've heard you could also use a little petrolium based vasoline
if you have a difficult time getting some tranny assembly lube.
If you can find the right size threaded studs... there are two places to screw em in and use them as guides to center the gaskets and valve body on....
But i stuck 3 bolts though and got everthing lined up and then started the rest of the bolts.
You'll also need an inch lbs torque wrench for the valve body....... but i'm sure you already know most of this if you rebuilt the tranny yourself. /forums/images/icons/smile.gif

Good luck! /forums/images/icons/cool.gif