What to look for on used JGC

My wife wants a GOOD used Jeep GC. How long do the trannys usally last? What to I need to look out for ? Any suggestions would be a help.

my suggestion is to make sure you get a warrenty with it. I bought one brand new in 05, tons of problems with the rotors warping (dealer said it was normal), and then at 30,000 the transmission started slipping, ultimatley being replaced, and at the same time the seals in the rear axle had to be replaced. Then a few thousand later the front shocks had to be replaced, and then the left rear. I know what your thinking.. rigourus off road driving. WRONG. it never left the highway. im not sure if i just got a bad jeep, but ill never buy one again.