I have a 2001 chevy blazer 4x4 and its trans is pretty much spent. I have a buddy who has a 2001 trailblazer with a basically new trans for the same size engine but it's not a 4x4... Is that gonna make a difference?

 

Yes. It won't fit.

 

Tom is correct.

A 2wd and a 4x4 4L60e is not going to be interchangeable.

You need to stick with a 4x4 trans, but you do have a little flexibility on the year and even what the trans came out of. I want to say so long that it was bolted behind a 98-05 4.3 V6, it should be a direct drop in. There's some differences in the early ones, they had one piece housings with integrated bellhousings, then later on the bellhousing became a separate bolted on piece. Too much later and I think there's a speed sensor in the tail housing that the prior ones did not have.

Hoping the user Transman will step in with a little more guidance