aR.

I know it is Not a new topic as a whole of stuff is written on it which I am going to ask about but there is a tons of "conflicting / contradictory and some time confusing information" on this subject ? which I have been reading in last couple of days.

Please bear with me as I am New to E60 as well as to this forum and also somewhat less informed.

I have a 07:550 which came with 124s and I am ready to replace those with 166s. My question is in regards to the size of tires to run on this. I understand that M5 comes with a bit wider tires (255/40 on the front and 285/35 on rear)- I have even seen one member running 245/40 in front and 275/35 in rear. But many posts here suggests to run 245/35 in Front and 275/30 in the rear for a 550.

The question is why..Is there a concern of rubbing in a smaller wheel well than in the case of M5? Did anyone actually put on the real M5 size and had this issue or everyone is just worried and simply guessing about it?

Another question is in regards the use of the spacers..I have read some place that somebody recommended like 12 mm spacer(or a 10 mm spacer) for rear? Would it not be better to run the actual M5 wider tires without the spacer or spacers are needed to clear the inside of the wheel well from this "extra 10mm of the rear wheel? I also read that some members are running the actual 285/35 on the rear without any problems ? I even read using 285/30 in the rear also ? like Lomag is doing with No spacers.

Moreover, one Member, I believe M53odt is running 265/30 on the front and 285/30 on the rear BUT with 9 1/2 inch wide wheels - Not a staggered set. This is being achieved by using an even lower profile tire - 30 instead of 40 in front and 30 instead of 35 at rear -reducing the tire profile by 5 mm. How does that perform in ?pot hole? situation and the overall life of the tires?

Another item is using very thin- like 3 mm - 4 mm spacers on the front. Some people are using it - and others and Not. Why is that the case? Any comments.

I would really like to get to bottom of this so I can make this decision. Thanks a whole lot to several of you whom I had written privately and gotten their valuable input.

Thanks again for your feedback.

550isport

Wow,

I'm glad I was poking around on this forum. I am ordering style 166 M5 wheels this week for my 550i due for delivery later this month. I was going to buy the exact same size as the M5 255/285. Now I read that the 255 front rubs? Is that confirmed and is there a work around to allow you to run those tires?

DRP

Lomag

You can not use the standard M5 tire sizes because their diameter is larger and it's going to throw off your speedometer and they'll also raise your car by half an inch plus maybe cause other issues down the line. The front's also won't fit but the rears might. Basically, when you upgrade the rim size by 1" you must decrease the aspect ratio of the tire by one level and you generally keep about the same diameter. So with the 19" 166 wheels for the E60 your choices are 245/35/19 for the front and 275/30/19 or 285/30/19 for the rear.