This might be stupid, but I'm wondering if 245/45/18 all the way around will fit without any issues...

I have a 2004 545i with sports suspension. It comes stock with 275/35/18 in the rear and 245/40/18 in the front.

 

we would recommend sticking to the stock tire sizes as it is a staggered setup

 

+1

 

I am getting an pretty amazing deal (almost free.) My friend just sold his car and these were left over so that's why I was asking. I don't need new tires at the moment but wouldn't mind getting some if it's almost free.

 

The difference is the stagggered wheels have slightly different widths ... but, IMHO, for most average driving it won't matter. And the minor size difference (245x45 vs 245x40) is also slight ... in fact F10,s are now fitted with 245x45/18's. If you want to see the actual difference here is a tire comparison website Tire size calculator

 

Thanks, I just want to make sure that there will be no rubbing. Looking at the numbers I will see a 1.5" increase in diameter at the top (3" total) which hopefully shouldn't cause any rubbing...

 

i doubt you will have any issues. it is a bit of a taller tire, but nothing to write home about...

 

I have that size all around on a 2007 530i with sport suspension. The only time I've had any rubbing was in the front when hitting a tall driveway cut at a higher speed than I should have. Doctor, it hurts when I do this....so I don't do that any more. My wheels are all same size, not staggered.

 

It will fit BUT I wouldn't do a square setup with 245's all around on a 545i. Just keep the extra tires for the front.

 

If you have 275 wheels on the back, you can't put 245 tyres on them, surely? Or did you mean change the wheels too?