exhaust problem
and to answer your question NO
when you change rim size, you have to alter the tire size to accomodate it. basically you run a different tire, but it has the same overall diameter.
16, 17, 18, 19" rims dont affect the tire diameter...its the TIRE that affects the diameter.
16" rim with 245/50/16 tires are 25.7" in diameter
17" rim with 245/45/17 tires are 25.7" in diameter
17" rim with 245/40/17 tires are 25.7"
18" rim with 245/40/18 tires are 25.7"
get the picture
the exhaust is the problem...fix that
you can try raising the exhaust up by modding the hanger, or depending on how big of an issue, you can use a body hammer and dolly to make a slight divet in the exhaust.

