Hi everyone. I've got my 530xd in the winter and it's time to change to summer tires - I'd like to combine it with changing rims as well, however I'm newbie in this topic. Could someone tell me what width and ET should I be looking for? I'm aiming for 18" or 19" rims, preferably 18" and I'm planning to put 245/40 R18 tires on them. Right now I have 17" (probably style 138) rims with 225x50 tires. Any help? I'm kinda lost in this topic. Also from what I've read xDrive further complicates this topic?

 

Welcome to the forum! There is a wealth of information about rims and tires for xi cars on this forum, but I understand it can be a bit overwhelming, so let me distill it down to some of the basics.

BMW AWD cars (xi's) have a different offset from their RDW cousins ("i" cars). Standard offsets for xi cars range between ET 35 and ET 45. Go lower than that and you start running into problems. Basically, the lower the number the more the wheel sticks out. The higher the number the more the wheel sits inside the wheel well. Rims with too low an offset can cause troubles with the outside edge of the tire rubbing on the fender or wheel well. Rims with too high an offset can cause troubles with the inside edge of the tire rubbing on the suspension or wheel well.

I have a 530xi. Stock for my car is a 245/40R18 tire with a 43 offset. The first number is the width of the tire and the second is the sidewall height. Rim widths range from 7.5 - 9.5" normally, but can go higher with rear staggered tires, but that's a whole 'nuther topic. For now, just go within that range. What tire/rim combinations you choose ultimately depends on your preferences. A good site to consult is WillTheyFit, where you can compare different tire combinations. If you have more questions, feel free to ask.