I have a 2012 C350 coupe with 19 inch wheels, when I hit some bumps the outer wheel well lip rubs the tire, how can I stop this without dropping to 18 inch wheels?

 

Use wheels with the correct offset.

 

^^^^ That's pretty much the answer.

What are all the specs of your current wheels and tires?

PS - Welcome to the internet. You don't have to post the exact some comment in a handful of different threads to get a response; one post in the appropriate thread would've done the trick just fine.

 

You could use a different make of tyre in the same size , you wouldn't believe the differences in sizing...