Wheel Balancing - Ughhh,..

[SoarinZHP]

I had a flat about a week and a half ago. I took it to Discount Tire to have it fixed. Every car I've had for the last 16 years has been to see Discount Tire. They fixed it without a problem. While it was there I asked them to cross and balance the wheels. Ok... So, I drive off and it felt fine. I get up for work the next morning and I'm saying, WTF? There's this irritating vibration at 45,53 and 65 MPH. I make another appointment to have them rebalanced. Take the car in. They do it again. It's still not right. I'm getting irritated. I figure if the monkeys at the first location can't do it, I'll take it to another. I had them pull all the weights and start from scratch. Even a ceiling fan can be balanced... They spent some time balancing, checking wear patterns, flat spots, etc. They tell me it should be fine. It was still jacked up....

I had enough of that crap. I found a performance shop that does a lot of cars used for tracking, upgrades, coil overs, etc. They weren't surprised when I told them my story... I had them peel on the weights of AGAIN and start from scratch. After spending 45 minutes with it, I am told it is ready....

I spoke to the tech who did the work and asked him how it went. He told me they were all off about 1/2 gram. 1/2 gram?!?! I can't imagine 1/2 of a gram would make that big of a difference....

I take the car home. Absolutely amazing. I still can't bel

So.... Has anyone else had a similar experience?

Are our cars built with such narrow tolerances for imperfection?

[johnrando]

Wow. You are scaring me. I usually go to Discount Tire too. Not sure why the problems. Just curious, stock wheels/tire sizes?

[az3579]

I had that same experience when I went to the Mafia meet and got my wheels mounted to my existing tires down there. I could have sworn the tires were defective (all of a sudden, after the changeover mind you :shifty) based on what the guy was telling me. Well, they were, just not in the balancing department. Came back home, had them rebalanced, and all was well (relatively).

[SoarinZHP]

Out of the box stock... Typically I've had very good luck with 7 previous vehicles and never had a problem.

Hence, my question about the narrow tolerance due to the suspension or the profile of the tires....

I'm just happy to have the ultimate driving experience in my not so special car back.... Imperfections in wheel alignment (any pulling or deviations in tracking), steering wheel placement (the wheel better be completely centered when I'm driving straight) and vibration bring out an out of control, raging lunatic in me....

Then again, most imperfections in the car in a tactile or aural sense drive me batty. Rattles especially. Ever been driving around and something is rattling and you go bonkers trying to find it only to discover it is the garage door opener sitting in the ashtray?

[johnrando]

lol, +1!

[Oli77]

I just did a little calculation and at 50 mph, a 17 inch wheel is rotating ~660 revolutions per minute.

A 0.5 gr weight error at this rpm should not throw this off that much.

At work, we spin things at 5000-20,000 rpm (about 10 times faster than the measure above) and a 100 milligram difference does not throw things off (granted the radius is a little less at work). I would think we should tolerate 1 gram difference but I am not a tire balancer just a back-of-the-napkin calculator :).

[SoarinZHP]

Man... I wish I had the know how to figure out and explain the above post. Impressive. All I know is I am a happy man... And the not special pleasure I receive from my car has become even more not special.