Friend bought new M4 wrong tires?

[TopJimmy]

You have no recourse. The car is used and the tires aren't "unsafe" even though they're way off from right.

Just get a proper set of 265/35 fronts and 295/35 or 305/30 rears. MPS4S is good for street use. If you plan to track get a dedicated set of wheels and tires for that.

[TideMD]

Originally Posted by brad850csi

Definitely 245/45r19 and not 245/40r19 or 245/35r19? They'll be very tall.

Perhaps go to tirerack and look up the model of tire and see what their rim width spec is? I looked up a few 245/45r19 and they have a maximum width of 9" - then perhaps contact the tire manufacturer and see what they say about running that size tyre on a 10" wheel.

I'm sure at that stage a single paragraph explaining the situation will be enough to scare the dealer

Another factor is that the tires on the site linked above (assuming it is the same car in question) are run-flats. To my knowledge, BMW has not approved any form of run-flat tire for use on M cars.

Unfortunately, this seems like a crappy situation for the buyer, as the only recourse is likely to fork out more money and mount a proper set of new rubber. As always, "caveat emptor."

[TopJimmy]

At least he gets to pick a good set of tires. That's the first thing most of us change anyway. My M4 came with factory size MPSS on 437s and they got swapped with BBS and Bridgestones on day 2.