New Tires + Wheels Balanced Twice = Still Shaking

[William330]

Just installed new tires at a local place last week, and felt the steering
wheel shake afterwards (it shook most at about 40MPH).

The steering wheel never shook -- always rock solid.

So I took it to the BMW dealer and had them balance the front wheels again.

They said the balance was off by "30 grams, that's a lot."

OK. It's now better, but still vibrates.

Any ideas? Is it possible the tires were not installed centered on the rims?

I once read about a machine that spins the wheel, and sands down the high
spots on the tires. Seems like overkill, but if it works...

I've now already dropped $300 on tire installation, between the first shop
and the BMW dealer. This is crazy.

Updated: Did some googling and came across this machine:

http://www.gsp9700.com/pub/features/how.cfm

Looks effective.

 

[ThatOneGuy]

It's possible, even though new, you've got a defective tire.

 

[William330]

It's possible, even though new, you've got a defective tire.

You know, when the tires showed up, some had a small white dot painted on
them (about a half inch around). I wonder if that means "factory seconds"?

I ordered them from tirerack.com -- could that be how their prices are so much
lower than at a tire shop?

I'll investigate if the front tires are the ones with the dot (can't recall now).

On that http://www.gsp9700.com website above, you can search for shops
that use the "road force" balancer, and my local BMW dealer fortunately
has one. The machine can detect defective tires (uneven sidewall stiffness).

Other than a defect, I have a hunch the first shop didn't seat the tire on the rim
properly.

 

[Big Daddy]

William I think you are on the right track, have the dealer use their "road force" balancer. If they appear to be way out of balance or around they should be replaced. I too have seen the white dots and although I cannot remember what or why they are there it is not an indicator of seconds.

 

[standheizung]

William I have had that problem before.

Here is my guess. No wheel is perfectly round and no tire either. However, they are built to a spec so that "generally" the vibration is minimal. Sometimes, the high side of the tire and the wheel can be aligned, so that together they are out of spec. This happened to me a couple times.

In order to fix this problem, i would suggest trying two things:

1. Take the tires back to the original installer and have them rotate the tire 180 degrees on the wheel. If this doesn't work, try 90 from there. And finally another 180, so that you will have tried 4 different configurations all up.

2. (This is something you can do yourself) Exchange the front tires with the back. If the vibration is slight, it will not bother you as much on the back.

 

[William330]

Thanks for the tips and suggestions!

The original installer is 'fired' as far as I'm concerned (other issues not mentioned, besides the bogus tire balancing). And unfortunately, you can't swap front tires for rear on a 330, as the rear tires are wider.

My current status on the tires is this: At about $350 on tire installation alone, I've decided to cut my losses and let them vibrate / wear as-is.

And next time, a BMW dealer will mount and balance the tires.

When I took it back to the BMW dealer for follow up, they said:

1) They balance ALL tires they touch with a "road force balancer" (see earlier post above).

2) Since they did not mount the tires, and were just doing a "clean up" balancing from the previous shop, they said any further action is now an "investigation of a front end shimmy" and wanted to charge me for 1 hour labor ($125) to locate the problem (waived if I decide to have them "fix" whatever they discover is wrong).


So I'm shutting the process down. No more money flowing out the door on these tires.

My only concern is that the slight shimmy may damage the wheel bearings or some front end parts, but that's (hopefully) just me being overly paranoid? (It's really a slight shimmy, as if the tires are slightly out of balance.)

All this said, the original BMW factory tire installation was dead perfect -- smooth as silk, no vibrations.