I'm going to check out a 1995 ford explorer 4x4 with 90k miles.

What are some things i should look for? Are there any common problems that I should know about?

 

Ball joints, rusted out brake rotors, leaking rear axel seals, Exhaust system, radius arm bushings, leaking valve cover gaskets. tune up?, Look at it straight on and see what kind of wheel pitch (camber) it has, also check surface of the tires for cupping, if badly cupped could be a condition you will continually see.