transmission trouble

[Benjamin Henderson]

I have an 88 Chevy suburban and a few months ago i left work, On the way home the truck started slowing down with the engine needing more throttle to keep up the speed. About halfway home it stopped pulling and when i get out of the truck i noticed a puddle of transmission fluid under the front bumper from external transmission cooler. After getting it towed home, fixing the leak, and refilling the transmission I take it for a test drive. Now it has a problem shifting and no reverse. I now have to high rev it to get it shift and when I put it into reverse on a very flat area an rev it up it very high it will barely moves. Any ideas on what I should do would be great!

Thanks Ben

 

[7thdarkangel]

Sounds like it needs a rebuild.

 

[df2x4]

Yeah, definitely sounds like you cooked it.

 

[Benjamin Henderson]

Well dang it I was afraid that I might hear that. I think that I have TH 400 and since that would require taking the transmission out anyways, I was wondering about swapping it out with an 700r4 trying to save more fuel with that gas hog as much as possible. Any thoughts on that?

 

[df2x4]

I wouldn't. You'd probably need a different driveshaft to make it work, the TH400 cases are longer than the 700R4 by about 3 inches. Not to mention you'd be giving up a ton of strength and reliability.

 

[Benjamin Henderson]

Sorry But my Suburban is 4 wheel drive i don't think that will matter since the transmission tail shaft comes off for the transfer case to bolt to.

 

[df2x4]

In that case I'd be more concerned about the transfer case interchangeability. Don't the 700R4 output shafts have a different spline count than the TH400?