Tranny upgrade?
 

iOk so I have a 96 blazer with the 4l60e. First gear went out so I figured this could be an opportunity to upgrade possibly. What I plan on doing in the long run is lifting it and putting some 38s under it. Now, I'm looking for a transmission upgrade that will do good with tires this big but without too much modification. I was looking at getting a 4l80e but that would be way too much work. Should I go for an upgrade or get a different transmission like a 350 turbo or just rebuild the one in it for a couple hundred bucks?

couple of hundred? try 1500-2000 bucks. tell em you want the beast sunshell,and stuff for high torque towing.

did only first go out? or is 4th gone as well? if so its just a failed shift solenoid.

My mechanic said he can rebuild it for $300 parts included... And no its just first, it grinds real bad but when it shifts to second its fine and it goes all the way through to 4th and OD just fine.

you need to make sure hes doing a full rebuild. Just the kits are 150+ I dont know anyone who will dig into one for less then 600.

What did he say, I'll put some upgraded parts in and fix the first gear problem, if that's the case fantastic!
That price kind of sounds like a new solenoid, a good shell at a good price alone is like half that.
Why don't you just let him get it going properly for the three bill's, then you have the time to figure out exactly what you want to do with this.
Time for research, you would need to add a zero to do a top notch job.

If you are building for 38s, now would be a good time to replace the whole drivetrain, from the engine right to the axles. A 4L60E is fine behind a 4.3, but once you go to bigger axles, tires and a bunch more weight you will want a V8 of some sort.

$300 your mechanic is only repairing it, not rebuilding it.