[X2 Monstah]

At about 15000 miles, I was receiving vibration and thumping from my front tires on my 2016 328i. I had an alignment done at the dealership and new Continental run flats put on because my front tires were badly cupped. Now, 5,000 miles later, I'm getting the same symptoms. I drive mostly highway and haven't hit any potholes, curbs, etc. What would cause my tires to be cupping again? Two alignments and two sets of tires on just over 20,000 miles is ridiculous. I'm starting to think the dealership never did the alignment, knowing i'd be back soon for yet another set of tires. Any thoughts?

[bimmer456]

The tire manufacturer may cover for road hazards if you still have sufficient tread dept.

[rak299]

Are both front tires cupping? If no, my guess is a bad shock. If yes, I would take it back and ask that they recheck the alignment. (probably screwing up the alignment is more likely than not doing)

[goj]

Pictures? Something is not right here tire cupping usually happens when your shocks are completely useless. If both front tires are exhibiting this than you likely have 2 bad shocks.

You or someone else hit a large bump/pothole or damaged the car. Check the strut towered to make sure everything looks bolted up normal. If it does, take it to a reputable independent shop or to the dealer to inspect your suspension.

[wdeerfield]

i dont think its bad shocks but you need to check your toe in on the front. i had the same thing with my continental rft tires but am not having the issue with my snow tires. maybe its the tires as well. get a before and after measurement of the alignment. (verify the timestamps of the readings if possible)

[X2 Monstah]

Thanks for the replies. I'm having an Indy shop check the alignment today. I'm also going to have all 4 tires re-balanced. The cupping is at the very initial stages. I hope an alignment and re-balance will help. Once done, do you think the tires will begin to wear normally (again, they are at the very early stage of cupping), or are the tires crap now? I really don't want to replace the tires again. And I certainly don't want to spend the money on better, non-RFT tires if the car has a serious problem.

[X2 Monstah]

Okay, this may be complete BS, but a guy at work just told me the cupping is cause by my rear deck spoiler. He says at speed the rear of the car is being forced down, therefore lifting some weight off the front tires. He says the front tires are then "bouncing" and causing the cupping. He insists if you have a rear spoiler, you must have a front one as well. At first, I though he was talking nonsense, but...Hmmmm.

[BlueCrabMafia]

Originally Posted by BSM F30

Okay, this may be complete BS, but a guy at work just told me the cupping is cause by my rear deck spoiler. He says at speed the rear of the car is being forced down, therefore lifting some weight off the front tires. He says the front tires are then "bouncing" and causing the cupping. He insists if you have a rear spoiler, you must have a front one as well. At first, I though he was talking nonsense, but...Hmmmm.

Complete and utter BS.

[X2 Monstah]

Originally Posted by BlueCrabMafia

Complete and utter BS.

Thanks. I was hoping to hear that response.

[vgore]

Originally Posted by BlueCrabMafia

Complete and utter BS.

LOL the stock spoiler is too small to generate any significant down force. It is only good for looks. Unless you have something like this

http://www.racecar-engineering.com/w...tm/zupdtmh.jpg

[X2 Monstah]

Originally Posted by vgore

LOL the stock spoiler is too small to generate any significant down force. It is only good for looks. Unless you have something like this

http://www.racecar-engineering.com/w...tm/zupdtmh.jpg

That's exactly what I have!

[goj]

Op - please post pictures of your tires. Seeing it will give us a better idea of whether it's alignment or something more serious

[X2 Monstah]

Originally Posted by goj

Op - please post pictures of your tires. Seeing it will give us a better idea of whether it's alignment or something more serious

Pics don't show anything. I can feel the cupping by hand, but photos from several angles don't really show anything. The cupping is very minor at this point, but enough to be bothersome.

[liveevil]

Originally Posted by vgore

LOL the stock spoiler is too small to generate any significant down force. It is only good for looks. Unless you have something like this

http://www.racecar-engineering.com/w...tm/zupdtmh.jpg

I have a huge Js racing Gt Wing on my Honda S2000, and I never experience cupping.

[BlueCrabMafia]

Originally Posted by BSM F30

Pics don't show anything. I can feel the cupping by hand, but photos from several angles don't really show anything. The cupping is very minor at this point, but enough to be bothersome.

So are you feeling peaks and valleys?

[BlueCrabMafia]

Originally Posted by vgore

LOL the stock spoiler is too small to generate any significant down force. It is only good for looks. Unless you have something like this

http://www.racecar-engineering.com/w...tm/zupdtmh.jpg

Just a bit of FYI, spoilers (regardless of size or shape) generally don't start developing down force until around 90mph.

[X2 Monstah]

So, after two sets of tires, two alignments, and re-balancing the tires, I was finally able to get a smooth-running car again. The vibration/whoomping that was driving me nuts for months is gone! The culprit? A bent rim on the front driver's side. Not sure why that wasn't found earlier, but I now have the rim repaired and I had a set of Continental DWS 06's put on. Drives like a dream! I love my car again.