Bert

I recently bought a set of very slightly used winter wheels with snow tires. They had already been balanced for the guy who owned them before (he had them on an '06 GT that he decided not to drive in the winter any more) and he said they were fine / no issues. (of course no way to tell whether that was 100% true)

When I installed them, I noticed a vibration in the steering wheel at around 50-60 MPH. I figured one of the fronts was out of balance, so I took them to the local shop to have them rebalanced. (I explained what was going on and assumed he would check them before he balanced them . . . but later when I asked "how were they" he said "oh we just strip everything off and start over, we didn't check them first")

So then I did the highway test and the vibration is still there. It is not present at all speeds, seems to be worse when there is no load and no turning, coasting at 50-60 MPH is worst. You can see the steering wheel shaking about 1/8" if you let it. Under some conditions it feels fine, under other conditions it is very noticeable.

So I asked the shop -- he said "One of the tires must have a slipped belt. Best we can do is put it on the back" (and of course took the opportunity to remind me that since I had purchased them used all bets were off).

So my questions are:

- Is there any way to tell by the way it acts whether a wheel/tire is out of balance versus a problem with the tire such as a slipped belt?

- Should I take it to someone else to check the balance, or just swap it to the back like he suggested?

- Or will there always be some vibration with snow tires? (I've never noticed this before with other cars, but the 'stang has less play in the steering so it is possible that this would not be noticeable on a different car)

thanks in advance!

cinque35

They should never vibrate.
Take them somewhere that has a Hunter GSP9700 balancer.
You could find one in your area on the link..
http://www.gsp9700.com/









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Bert

thanks for that, there are several close to me, no surprise the local guy I went to is not one of them, interesting info on that page . . .

cinque35

Yeah I had a set of tires done at Mavis that vibrated, had to bring them back, still no good.. Brought them to Firestone, also twice! still vibrated over 50mph, I was ready to throw them out..
Then I went to a place with one of those machines, which was a scary little shop, and they got them right first shot, no problems since

karman

The family owned downtown place I always recommend has no fancy showroom or big parking lot.
They do have one of those machines.
I bought a very large set of wheels and tires for my old 4X4 at an el-cheapo place.
The cheap shop I bought them at couldn't balance them even after many tries.
They shook like crazy at speed and wore a little funny after only a couple hundred miles.
My downtown shop was able to balance them perfectly even with the odd wear on them.

bob

What is the brand of tire on your winter wheels? Also the term "slipped belt" is pretty dubious, and nearly as bad as the ubiqitous "broken belt"

If a belt has slipped in the tire, it should pull like an alignment problem (a very good example of this would be the Yokohoma tires frist fitted to the Acura NSX - they were intentionally designed with steel belts placed at different angles creating a load on the suspension) This is also commonly called radial pull.

There is alot of things that can screw the balance on a wheel - dirty mounting surfaces can **** the wheel when it is mounted on the balancer - something the thickness of a business card is enough to throw off the balance (as an example).

Do you have hub centric or lug centric wheels? Lug centric wheels require a pin plate or other method to afix the wheel to the balancer by the lug holes in the rim. Hub centric wheels would just use a centering cone. Also lug centric wheels on a vehicle supporting hub centric wheels might require hubcentric ring spacers to proper locate the wheels

Was the balancer calibrated and do they actually zero out the balancing operation? Balancers typically zero out at slightly less than a quarter ounce of weight. If the tech is balancing down to a quarter ounce the imbalance could be greater since the balancer rounds to the closet quarter ounce but still might not be that far from a half an ounce out.

If the rim/tire assembly is mis matched (there is a function known as match mounting) even a balanced condition will act out of balance.

Lots of stuff can go wrong, but usually a "slipped belt" isn't one of them.

Bert

Thanks Bob! . . . .

Mastercraft Glacier Grip II, 235/55 R17 -- see photo
Yes I know these are not top-of-the-line tires, but for $500 with the wheels I couldn't resist

yeah, I think that is code for "you should have bought the tires from me and you wouldn't have this problem"

there is no pull that I have noticed (this car always pulls a little but I think it is just sensitive on-center steering, no difference with the snows versus the normal P-Zeros)

I thought the shop would have all that under control but now I am having my doubts

I believe they are lug centric . . . standard Mustang GT stuff, I do not remember any hub that engaged the wheel when I installed them

I don't know and I think I would be wasting my time to ask, they are going to say "everything was right" . . . probably better off going to a different shop

I don't know how I would detect that; hopefully a better shop can do it . . . but I have no reason to believe there is mismatch

yeah, I got the feeling that is mumbo-jumbo to confuse the customer and ward off any further probing questions about the shop's equipment, personnel, or techniques