I ran into the same problem on my previous ride, an E39 98 540 six-speed. When I switched from 245/40-18 BFG Comp T/A ZRs to g-Force KDs in the EXACT SAME SIZE, I ran into fender clearance problems. (This was the last model year prior to the staggered OEM set-up). Apparently, even within the same brand, there are differences in sidewall 'height' and stiffness that will have an impact when it comes to fender clearance. I opted to have the fenders rolled slightly at a body shop. BTW, my Service Tech said some suspension settling is common, and could have contributed to the condition. Needless to say, I didn't expect this problem when I switched tire models of the same variety!