From the info handed down to me when I was looking, check for loose, missing and or broken bolts where the rear attaches to the frame..cracked rear end housing, or broken where it attaches. Check the drive shaft to see if everything is tight and not loose... But I guess that would be a normal check as in a GT....
I ALWAYS check to see if the fan is intact, but you'll notice that as you are looking at the drive shaft.
Check for cracks in the frame. Seeping steering cylinder, heck, about all I can think of off hand. What model you looking at?
Good luck
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