So I'm in the process of overthinking this, and thought I'd turn to the forum with that.

2007 MCS, city/hwy driver, replaced the OEM tires with Kumho Ecsta SPT runflats, those stayed on for 2 years, and I admit I didn't rotate enough.

So the rear tires ended up with really bad cupping. No evidence that the suspension was to blame, dealer said suspension (sport) is OK. I've read enough to know that the cupping is common.

Replaced all four 2 years ago with Potenza G019's (non-runflat) and now those are showing the same kind of wear, but not quite as bad -- I've rotated more often but still not enough, but the noise is getting bad.

The front tires don't show visible wear right now. So I am (over) thinking the following options:

1. Rotate the tires now (I don't do it myself), put the cupped tires on the front and have them judge whether the cupped tires are bad enough to replace. They should be objective as I wouldn't buy replacements from them anyway. (Tirerack for me.) Then replace the two cupped tires if they're judged to have excessive wear.

2. Go ahead and replace the two rear G019's only. But with rotation the front will need replacement in another year most likely anyway.

3. Bite the bullet and replace all four (I am thinking of going with current-gen runflats if I do that) and promise myself I'll get rotation/alighnment often, and get at least two years out of those. I can afford it and I expect to keep the car another year or two.

Now that I write it down, I'm thinking #2 sounds like the sensible thing, unless I really want to go back to runflats, which is a whole 'nother argument, hashed out in many a thread, and I won't ask for advice here.

 

Option 4. Find the cause/source of the cupping and fix that before buying new tires, which otherwise would probably also experience cupping.

A puzzle, considering no evidence that the suspension was to blame. From what I've read, cupping (scalloped wear along the edge) is usually due to worn (or bent) suspension parts. Worn shocks is a favorite suspect, but other suspects include ball joints, wheel bearings or bushings, and even springs. Re-check tie-rods and wheel/tire balance as well.

If your tire had a feathering wear pattern instead, that could be due to a bad toe alignment setting, but I'd suspect something is worn or bent as a cause for cupping.

 

A good independent shop with alignment capability should be able to help you shake the wear issues down. This will protect the replacement tires from the same issues.

 

I looked over our listings, and found a BMW/ Mini specialty shop. I called them for you and
they do alignment work.

Terry Sayther Automotive

 

Flip them: have them remounted on the wheels so right hand tires now mount on the left and vice versa.

 

Thanks all -- I think I just needed a nudge out of the rut.

Option #4 is definitely a component of 1, 2, or 3.

I think perhaps having it diagnosed with the wear on the tires might be easier than telling them "trust me, there was cupping, see if there's a problem."

 

Okay, so I am having cupping issues on the rear of the Yokohama AVID ENVigor tires that I put on my 2007 S 20,000 miles ago. It is just showing early signs of this issue, and the noise is not terrible, but noticeable at highway speeds.

I had taken the vehicle back in to my local shop where I had them first installed, after having them shipped directly from Tire Rack. It needed front pads/rotors and I was going to have them rotate at this time. That's when they pointed out the cupping and told me not to switch them out now.

They had done balancing and alignment when installed 20K miles ago.

The comment they made to me is that this is a common issue with this vehicle and the only way to really deal with it is to rotate every 5K miles so they wear better, but since I let it go too long, my best option is to purchase two more matching tires, dump the back tires, rotate the fronts to the back and install the new ones in the front.

Sound right?

I have 85K miles on this car, and this is the first time I've experienced the issue, although I probably rotated closer to 15K in the past. Any reason one brand or another may be more prone?

 

Agreed

I'd install your new pair on the rear.

 

Just curious, why? The theory I had been given is that the fronts wear faster, so if I install the new ones in the front they will start "catching up" with the wear that's already on the ones that are currently on the front.

Thanks for the answer either way.

 

Here is a great article on the placement of a new pair of tires.

 

Thanks, Alex. Makes sense now. (By the way, I couldn't get your link to work, but found the article your referenced here

 

I fixed it. Thanks.

 

For those that want to see some pictures of tire tread wear-

http://www.procarcare.com/includes/c...dtirewear.html

Rotating tires always is helpful if you care to wear your tires out more evenly, otherwise it can be possible to buy tires in pairs if you can get matching ones easily.

Best tires on the rears always best.

 

Well, add me to those with rear tire cupping. I have the General Exclaim UHP in 205/55/R16.The tire pressure has been kept at 35 lbs, and the alignment was checked and is OK. I am inclined to the comment above that it is a problem with these cars. Seems like a little engineering before the fact would have been good. I plan to buy two new tires, as the noise is too loud. Only about 6000 miles on these tires and not run in the winter. Disappointed.