I'm doing quite a bit of research on this as my 2015 X5 50i (F15) has the shudder problem at acceleration. Stops shuddering in higher speed turns. I've heard it all. Tire size, XCase, Traction/XDrive system.... I took it in to a local shop who only works on these types of vehicles and they couldn't figure it out. No warning lights or anything. Bought it about a year ago and has done it ever since. I cannot for the life of me believe it's the wheel and tires but who knows... brand new tires on 22x12's with 335 wide tires lowered on KW Coilovers. The local shop told me to take it to BMW which is 2 hours away. I do have warranty on it that i purchased with the vehicle given the mods already on it. What's the process of using this "Shudder Fix" stuff and where do i buy it? Just curious if i put in the xcase and fixes it it would narrow down my problem rather then spending thousands on smaller wheels. Thanks all!
