alignment & front tire cupping...

[blovatt]

I've recently been noticing a lot of "cupping" on the outer edge of my front tires... 2011 E70 with OE 20" Bridgestone RFTs -- 12k miles.

rear tires show very little wear at all -- certainly even wear...

I've been reading on this forum and a lot of other places that this is not uncommon for this car -- and that the dealer almost always blames alignment.

However, you never hear back from someone who got an alignment from the dealer and then stops having the problem (not that I've heard the opposite either).

The car tracks straight -- I can let go of the wheel and let off the gas at 80 mph in the center lane of a flat road and it does not turn.

Now that I look closer, I suppose there is a bit more wear on the passenger tire than the driver's side... but still, these cars seem to be very sensitive to road camber, etc... so I'm really not sure about the alignment.


To bring the situation to a head, I ran over a nail the other day and now need a new front driver's tire... I'm ok with replacing front tires every 12k if this is normal, but the rest of the tire seems like it has another 10k in it at least...

I ordered the same tire again (from tire rack for 30% less than what they want at the dealer!) because I have no spare and must get RFTs and I'm getting them installed Monday.

I feel like I should do the alignment, but if I take it in for the $300 alignment and it (the same wear pattern) happens again, I'll be aggravated.

I'm also contemplating keeping the passenger tire I'm replacing in case I get another puncture... not sure if this is worth it -- the tire is $325 shipped...

Anyway -- i'm running long here, so I'll stop

Any suggestions or advice will be appreciated.

[SpaceGrey_Tifoso]

There was a thread that I found last year that I thought was very helpful.

I had the same exact problem. I pointed out to the dealer when they installed a new set last November. New set from the Rack as well. I asked lets keep it as close as possible and please provide the report when I come to pick up the car.

Also try to find out who is the best technician in the shop for this.

So far fronts over the past 10 months have not had the inside edge wear that my previous set had.

Let me digg for that thread and follow up with a link

[SpaceGrey_Tifoso]

This was the thread I found helpful.

Good info starts on page 2 ...

http://www.xoutpost.com/bmw-sav-foru...-really-2.html

[blovatt]

Thanks! -- this is exactly the information I need.

The specific toe measurements that weasel provided are probably what I need to preserve the tires longer.

I will report back with my alignment info once I take it in -- probably mid next week.

[blovatt]

Actually -- weasel did provide some great info, but ard was the one with the suggestion for toe with less front tire wear:

0.02 to 0.04

[ard]

1. DONT use a BMW dealer.

2. DO demand that they set the alignment where YOU want it..not just 'somewhere in the BMW spec'

People think an alignment is like an oil change: "Yup, did it"... you need to know where to set it.

Keep the toe to the minimum of the spec and you'll be happy.

My two cents...I have a great guy that aligns all my cars (but cannot corner balance the P car) at a Big O Tire store. $99. Every bit the same quality as a $300 BMW rim job.

[ard]

Oh, speak of the devil...you posted while I was composing.

[autoque]

Originally Posted by blovatt

Actually -- weasel did provide some great info, but ard was the one with the suggestion for toe with less front tire wear:

0.02 to 0.04

What about the rear tires? Same toe setting?

What are the recommended values for camber front and rear?

[blovatt]

autoque:
I'm certainly no expert on this (I think some of the guys on the forum are/were actually BMW Techs, so they'll be able to answer more authoritatively), but the "recommended" settings seem to be +/- tolerances from a "target".

If you check that other thread referenced above a couple of people have posted their alignment reports -- there you will see their "before/after measurements", the "target data", and the "Max difference" (which I'm assuming is the tolerance that BMW says is "ok").

It looks like the target toe for both front and rear .05' (per wheel - .10' total), but that a bit less (i.e. .02 - .04) on the front helps with the outer edge cupping.

From what I'm hearing, you pretty much have to demand that the car is set-up as close as possible to the target, because the tolerances are quite wide.

I'm going to get an alignment next week sometime, and I'm not experiencing uneven rear tire wear, so I will post my alignment report when I get it so you can see how my car is/was setup.

Note however that I suspect I may have a thrust-angle issue due to my wife bumping curbs with the rear tires... i.e. she's not used to the wide rear tires on the 50i sport compared with our old 1st gen 3.0i...


ard:
Thanks for you suggestions -- I would love to go elsewhere for an alignment, but I'm not sure where. I've had nothing but on-warranty BMWs for quite a while, so I always just use the dealer for service (never had an alignment though) and don't know of a good alignment shop (or even a mechanic) that I trust to work on the car.

Not sure if anyone out there is in South Florida (West Palm Beach area), but if anyone knows a good place other than the dealer(s) to do this I'm all ears...

[F150 Duke]

I had the same problem and had it fixed last week. '12 sport activity. The front alignment was found to be out. My front tires were cupping and starting to get louder. The swaped the tires off the rims and switched sides. Then did an alignment correction.

By the way, I only had the cupping and noise. Never a pull to either side when going down the highway.