[johannes37]

Hi all

I had a 320xd GT (2018) for a few years now, but first time posting
The car came with 2 sets of 18” alloys (original BMW), they had the same tire sizes for both winter and summer. That is front tires 225/50/r18 and rear tires 255/45/r18.
The winter tires need to be replaced now, I called the BMW dealer today and they said I can’t run this rear tire size, i.e. 255/45/r18. Their recommendations was to buy new rear rims and run 225/50/r18 on the rear as well.
Would any of you have experience with this? We had the old winter tires for the past 2 winters with no issues, so I would be tempted to go for the same size as before. Would you have any thoughts on this ?
Thanks
Johannes

[Billfitz]

If the diameter of the front and rear tires is the same then no worries, especially as you've been doing it all along.

[bogdanmihaisavu]

As per BMW standard, for winter wheels only (is different for summer), you can't run your setup.
Long story short, for winter setup you have to have same J, same ET and same tyre size on all 4 wheels.
You can check on realoem for your setup.

[bogdanmihaisavu]

And below is the summer setup (all accepted sizes and combinations for your car).

[PJ Gross]

On my stock 400M wheels, I run blizzak ws80 235/50/18s.
Odometer/speedometer is still slightly overstated but closer than stock. No issues and have been great for two winters.

Putting them back on today for another Michigan winter