How much bump are you running in the rear? The gas tank is on the passenger side and adds a decent bit more weight over there. You should take a moment and update your profile with current build. I can't recall what you're working with. I'm guessing that you've got decent bit of lift and no adjustable rear arms to push the rear axle back....so you're pulled closer to the pinch seam there than you otherwise would be?? The gas tank is the only thing I can think that could influence a difference in respect to weight from side to side....and bumps might not be appropriate still.

Have a few pics of where you trimmed?

 

I have the 3" Mopar lift. I did not install the lift, but had the dealer install it. I don't think the rear had different bump stops included, but I'm not sure. The kit came with 4 rear control arms, but they are not adjustable. The driver side has not rubbed since I did the trimming but the passenger side has. I will post pictures tomorrow.

 

Looking at the Mopar 3" lift on quadratec, and I noticed that the specs do say max tire size 35". I mentioned that cuz they include all new fix length rear arms, so the axle does push back a tad, but I have to think the rear isn't pushed back as far as most kits with adjustable arms like to move it. When the rear is moved back that far (with adjustable arms), you run in to clearance issues with the rear sway bar links hitting the upper control arm mounts on the axle....requiring you to scoot the rear sway back and inch or so....which creates clearance issues with the factory muffler. So, I'm thinking the rear axle is still sitting a little frontward of center in the wheel well....narrowing the clearance between the tire and body. It's not a big deal, but outside of trimming more (if you can), I think the solution for you is just going to be more bump stop in the rear. Still guessing that it's maybe the gas tank adding additional weight....just enough to lean the passenger side of the body a touch lower and creating just a little less clearance than on the driver's side. hard to tell without seeing pictures of the difference in clearance between the two sides though.