4l60 to th400?

As I posted earlier I believe my tranny is about done, But I have a th400 sitting around. The bad tranny I think is a 4l60 that is stock from a 94 k1500 GMC z71 4wd. I was just wondering if my th400 which came out of a 81 2wd short bed chevy will fit and run properly in my 94. If not what donars will fit and run properly. Your Advise is much appreciated!

It will not fit. Generally 2wd and 4wd transmissions are not interchangeable.

Also, although the 400 trans is strong, the lack of overdrive and the lack of a lock up converter means it's a high-revving gas sucker.

Finally, the 400 trans is 27 years old had may have been sitting around for a while and may not work anyways. Even if ti worked fine when it cam out does not mean it will work fine now. I have had used transmissions sit around for a while; maybe the seals dry up or something, but sometimes they do not work right without a rebuild.

IMHO sell the 400 trans and put the dough towards a rebuild of the 4L60.I am not a big fan of installing used auto transmissions because it's way too much work to swap them to find out if they function properly.

Thats just what I was thinking, Thanks alot for your input buddy!