[Hiddenknife]

Hi folks!

I ve been searching alot on this topic weather you should pick OE tires for your BMW model or regular non OE tires. Interstingly i ve not yet found any conclusion on this matter if you should run OEM tires to avoid any potential xDrive issues or run normal non OEM tires because of the better price & comfort being non runflat. Nobody gives an clear answer why you should pick one over the other technically. Theoretically BMW approved tires have the same rolling circumference, being created specifically to meet the stringent low RC tolerances of xDrive.

Yesterday i found something very interesting. I compared two brand new tires one Pirelli Sottozero 3 (star marked) runflat and a regular Michelin Pilot Sport 4s non runflat of the same size, load rating and speed rating. 245/45/20 103V

In the photos attatched you can see the OE tire is slightly taller than the non OE one even if it has 0.5 mm less thread than the non OE tires. (8 for MPS4S and 7.5 for Pirelli)

I ve seen many people post around that if you mount tires based on the readings on the B pillar specs you are totally fine as long as it matches the exact tire size, load & speed ratings. But the question is, are they acutally the same? Obviously it seems they are not. Are we exposing ourselves to transfer case/xdrive issues? i dont know. Maybe we dont see an immediate effect on the drivetrain but maybe it stresses it s componets running non approved tires.

Making this post is not because i am an advocate of OEM tires but because i wanna see what othets think about this matter.