I've got a 1999 trailblazer 4x4 with a 4.3L. I'm looking to beef the truck up and am wondering if I should go with a new transmission or if there's any good aftermarket rebuild/shift kits for it. I'm doing the drivetrain first but looking to get about 350 to 400 horses out of it. Also wondering if anyone knows how many spline axles I have and wat size ring gear...? I have a GU6 RPO code so 3.42 ratio. looking to put an eaton posi on it n need to know both those things.

 

https://www.700r4l60e.com/store/home.php?cat=64

They offer everything from Transmissions to Rebuild kits to Shift kits. If you've never done one before be sure to do some research first. There are a lot of parts to inspect that the book doesn't tell you about. Or at least not the book I use. I've had to learn a lot as I go. By '99 they have most of the bugs worked out of these transmissions so a shift kit may be all you need depending on how many miles you have on it.

 

Your rear axle is the 7.625" gm 10-bolt. I believe your axles are 28 spline.

Are you looking for on-road or off-road use? For on-road and light/medium off-road, I would look at the Detroit Tru-Trac diff.

 

aright cool n i wouldnt b messin with the tranny myself just installing it. everything else i can do. would shift kits come with all new clutch packs?

yea on road, medium off road. honestly ive been thinking about getting fully adjustable air suspension...might sound greedy but do you know of any suspension that can handle off road but also drop it to the tires when i put my street wheels on it?

 

Blazin, here is a link that I am feeling:

http://www.transmissioncenter.net/st...build_kits.htm