looking at a 2001 Audi A6 4.2 Quattro for under 4k with 88k miles. I'm always worried about tranny issues etc.. any big issues with this year model?

 

You hit it... tranny tends to go out on V8s.

 

check the trany pan for leaks it shouldn't be wiped clean either.

So what your looking for is a dirty pan with no leaks.

your also due for the timing belt etc... cooling system... Valve cover gaskets... service $$$
$800 do it yourself.