Crack rim issues?

[LifestyleRush]

I have a friend with a 2011 E89 and he just cracked his 8th rim. He is super careful when it comes to avoiding pot holes and curbing wheels. Is he just unlucky or are other people having this issue?

[Vintage]

Many other people have had issues with BMW wheels, probably in large part because of the super stiff RFTs that they come with from the dealer. These tires transmit a huge load into the rims and they fail from time to time. It is a bitter pill to swallow as the RFTs are much more expensive that normal tires and then those expensive tires ruin your rims. I myself had a cracked 296 style wheel recently and NEVER hit a curb, pothole, or other road obstacle that would cause such a problem. Not that I would encourage lawyers to file suit, but jeeze . . .

search this forum and you will find many with the same problem as it is often commented on

[LifestyleRush]

He has the 19" sport package on RFTs which I think is the same setup you have. He constantly has to replace the rears.

[35is_GVA]

I have noticed a lot of posts regarding wheel cracks. Is this issue only related to US version of the 296 19" ? Are these wheels made of different mix of alloy for US market?

I have been on huge pot holes on numerous occasions and at all sorts of speeds. I do have it regularly checked for cracks. Nothing so far - been almost 2 years.

Are there any others with these wheels and do not have cracks from riding on potholes?

[Vintage]

Well, we tossed the RFTs and shod the car in Michelin PSS. Awesome. Yes, we have the sport package with the 296s and we had no problem until about 25k miles, then a rear wheel failed for no apparent reason. As a result, my wife picked out replacement wheels, the VMR 710s . . . you see below

[Mr. ///M3 RD]

Originally Posted by LifestyleRush

I have a friend with a 2011 E89 and he just cracked his 8th rim. He is super careful when it comes to avoiding pot holes and curbing wheels. Is he just unlucky or are other people having this issue?

I too had 2 cracked rear rims mind you the wheel was the OEM Style 296 (other people had similar issues) just make a search here on ("cracked rims" or 296 wheel cracks")

Suggest to your friend the following ...

A) Always make sure tire pressure is okay (I found my RFT lost air quite often just a few ponds). Checking air pressure weekly or bi-weekley is highley recommended.

B) He should change to non-RFT.

C) When traveling long distances with the roof in the trunk and some luggage add 10% or ~ 4 PSI more air pressure to the rear tires then specified by the OEM.

D) Consider changing the 2.5 Degree Negative Camber on the rear wheels to 1.5 or 1 Degree Negative Camber.

All four points above (A to D) have been recommended to me by a very knowledgeable US Tire Shop Owner.

Summary; You see the RFT have very stiff sidewalls along with the negative camber (point D above) and the possibility of reduced air pressure (loss of pressure) in the rear tires exserts forces to the inner rim of the wheel (where cracking takes place). Cracks start at hairline Cracks then open up and lead to air pressure loss. Cleaning of wheels and then inspect them for hairline cracks on the inner outer wheel rim is strongly recommended.

I've come to the conclusion that the most likely cause of wheel cracking is the fact that a) the tires are RFT with this heavy sidewall and b) the negative chamber. As one travels and the car goes over imperfections in the road like overpass and bridge expansion joints, manhole covers and other road imperfections it adds stress to this soft alloy wheel. As time goes by this build in stress will have to go some place and a hairline crack will be the result of that. If driving continues then this hairline crack will open up and propagate (mine was 3 inches long). In the end the pressure loss will take place.

The process is similar to taking a paper clip ... open it up then bend it gently back and forth in time it will crack and break apart.

Facts are;

1) No dammage can be seen (in most cases I've seen) for going thru a pothole.

2) Why only the rear wheels crack.

3) Why is there so much discussion in this Z4 forum on the rear wheel cracks.

Good luck to your friend ... hope his nightmare soon ends

[LifestyleRush]

Vintage those look great.

M3rd thanks for that wonderful response. Very detailed I appreciate it

[Pacemaker1000]

It's not just 296 alloys and not limited to the Z4
Here in the UK I have been told BMW will honour any fault even after warranty expires. Could be because of the following.

http://www.bbc.co.uk/watchdog/consum...w_latest.shtml

[zEdP]

I have a 2009 model with the adaptive suspension. Until now only one 296 cracked and was replaced by the redesigned version.

[Mr. ///M3 RD]

I simply cannot believe that 2 years have past since I posted my case here in the Dealership Review Thread (see link below) and the cracked wheel issue has still not been resolved by BMW.

I think about my spoiled 2011 vacation trip across the USA whenever I pass my expensive garden hose storage addition

Perhaps it will take another 2 years ... what you fellows think?

Dealership Review Thread ----> Click to go to post 28



The photo above ^^^ shows the damage done to the rim in 2 places from using tire irons to remove the RFT resulting in a bend wheel!

Photos below show my now permanent $700- US Garden Hose Holder ... also a close up of the crack that required a replacement wheel.