[Jockbmw]

Hi,

I’m wanting to swap my existing tyres for something a little more accommodating for the state of our local roads. My current setup is staggered 20” with 245 40r20 on front and 275 35 r20 on the rear. I was wondering if anyone had switched to 245 45 r20 and 275 40 r20 and if there were any issues with x drive. I believe this is stock tyre size for newer x3 but unsure if this will work on f25.

Cheers
Jock

[TEF]

Don't know much about 20" tire sizes, but believe the current X3 wheels have a 5 x 112 mm bolt pattern vice 5 x 120MM on the F25.

[richardodn]

So basically you're looking to go to slightly taller tires without buying new wheels. The goal front to back is to have the same rolling diameter. Your proposed sizes meet that goal. The other main consideration is rubbing. The new tires have ~.5" taller sidewalls but the same tread width. There is a potential for rubbing on the front tires while turning but you shouldn't have any issues in the back.

Since your new rolling diameter will be larger, your speedometer will read slower than your actual speed.

Ideally though, you really should be looking for 18" or 19" wheels to solve this issue.

[Jockbmw]

Thanks, I’ll check out the clearance and see if I think it will fit. If not I’ll look at picking up a set of 19” alloys and put some tyres on that.

[DannyX3]

Take a look at this fitment guide. I would go to 19’s.
https://www.wheel-size.com/size/bmw/...-xdrive20i—181

[chris55552]

I have the 310's 20 inch and wanting to downsize to the 369s in 19 inch I believe. Im hoping to reduce the weight of both tires and wheels and on all 4 corners, I hear it does make a noticeable but not drastic difference.