I agree with Frank.
You could see if your axle is not aligned easy enough with a tape measure. Make sure to measure in the same place on both sides.
Alignment shops might not always center your axle if the actual tire alignment is good.
Your axle will not always be centered depending on how loaded down you are.
I had this problem with my Jeep only on the passenger side. Wheel spacers took care of the issue. I am running Nitto Trail Grapplers 37x12.5 on Pro-Comp wheels with 4.75 BS. With the wheel spacers it is effectively 3.25 BS and I have no clearance issues any more.