I just purchased a Tahoe that had a bad transmission. I was told that 4gear didn't work. When I got there there was fluid all over the place and looes like it leaked from between the transfer case and at the rear main seal. At the time it had no reverse. The Guy gave me a quart of fluid and I drove it Home in second. When I got home I played with it a bit and now the reverse works as well as 1-2. 3 and 4 however do not.
I have rebuild a few manual transmission's so I am capable or handling this. I am just curious what I will probably be looking at being that it mostlikely was starved of fluid. Would it be bands? Servo? What is the usual extent of damage on these tranmissions?

 

if it was driven low on fluid it could be just about anything or everything, 4l60s are known for the reaction shell for reverse failing. Rebuilding a automatic compared to a manual is a whole different animal but can be done with a good manual and time.