I'm not familar with 99 rangers specifically.
But I'd look for:
Excessive clunking when at idle and put into drive & reverse.
Smell the oil and look at it. Should smell like oil only (not excessive gas) and it ought to be brown or black. No grey.
Look at the under side of the oil fill cap for grey. (should'nt see any)
Check the coolant for any signs of grey. (should'nt see any)
On the drive check to see that the tranny shifts properly. Not too firm or too soft.
Otherwise.. just use your judgement on tires, paint, interior, ect..
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