Question, recently after driving on the highway or long drives I've smelled what seems to be burning rubber or something similar coming from the rear wheels.

Diff?

Also, the smell is stronger on the drivers side.

 

Sounds like your toe has moved on that side, normally the diff will make noise at accel, decel or your LSD will make noise during low speed parking lot turns, typically hard ones, you would hear a clunk. Doesn't sound like the diff to me. But I could be wrong. Maybe try putting a hand on that tire to see if its hotter than the other side. Its really hard to say since I cant physically see it.

 

No noise like that coming from the rear.

I did try placing my hand on the wheels to see if one was hot, or higher temp than the other. I couldn't feel anything.

If the tire were rubbing on the inside of the car, where would it be rubbing? I could look there. That was my first thought, but I couldn't see anything.

 

Is the car lowered? If not I would at least try an alignment. If you can jack it up try checking the tires on the inside, anything that were rubbing would be very visible. Also check your axle boots, thats a long shot but they're rubber too so who knows. Maybe check your exhaust for something that might have gotten stuck to your muffler and melted onto it. I could see that happening and the smell coming out of your wheel well.