New tires improperly balanced. How often ?

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I just replaced some Continentals with General Gmax as05's. I was very disappointed to have vibration at highway speeds. Returned to the installer. They said all 4 were out of balance. Claimed the machine must have been out of calibration. Is this common?
 
It can happen. Most of the busy shops around here just do a static balance with lasers, so roadforce/dynamic balance is not standard. But any shop that sells tires should dynamic balance for free.
 
Bought a set of tires and alloy wheels from a major internet supplier. They were not properly balanced. Had a lot of weights on them, and far fewer when properly balanced. The internet supplier recommended and paid for the re-balance. No harm, no foul.
 
Bought a set of Uniroyals from the local Chevy dealership, which installed them - pretty bad vibration. And the paint marks weren't mounted anywhere near the valve stems. Went back, told them about the imbalance/paint marks, and after the service advisor (the guy that receives the car, whatever he is) tried to tell me he'd never heard of paint-mark-at-valve-stem and that it didn't matter, they remounted and balanced them and they're fine after 50K. I don't do tires at my shop, but when I discuss new tires with customers I always tell them if there's any imbalance go back to the installer ASAP and tell them to make it right. No excuse for anything but buttery smoothness from a new tire.
 
Mount tire with paint mark 180 op the heavy side of wheel ( if marked) to minimize balance weights. If you cant spin the wheel, if you require excessive balance correction, deflate tire and rotate 120-200 deg opposite where it was and HOPE it will balance better. The valve stem has nothing to do with the heavy side off the wheel in my experience. But that was in the 1970's smile If wheels are unmarked heavy side, spin them bare and find heavy side, then mount tire dot 180 opposite.
 
I just had a couple of rims bent back. Low profile tires and those 17 or 18 inch rims tend to bend easily from potholes. It's not always a balance problem.
 
Originally Posted By: ARCOgraphite
Mount tire with paint mark 180 op the heavy side of wheel ( if marked) to minimize balance weights. If you cant spin the wheel, if you require excessive balance correction, deflate tire and rotate 120-200 deg opposite where it was and HOPE it will balance better. The valve stem has nothing to do with the heavy side off the wheel in my experience. But that was in the 1970's smile If wheels are unmarked heavy side, spin them bare and find heavy side, then mount tire dot 180 opposite.
Once again, the idea behind matching the marks is about runout (actually uniformity, but it's a little complicated.), not balance. The idea is to get a *rounder* assembly - BUT - There is no standardization about the marks - color, meaning, etc. Same with wheels. So matching the marks MIGHT get you a rounder assembly - and it might not. The good news is that is doesn't cause any harm. If one wants to rotate a tire on a wheel to get smaller balance weights - Great! Just be aware that it doesn't get you a better balance - just less weights - AND - you might be screwing up the runout!
 
Just watching tires spin on my road force I visually see many tires that have run out, with a smooth turning wheel. It might have a little effect sometimes with the tread being further away from center, which will take more weight to counter. If a tire calls for over 2 ounces per plane, I will index it 180, and sometimes it cut it by 75%, and sometimes makes it worse.
 
I've seen a bunch of bent wheels, too. Having worked at a tire shop there's a learned helplessness in (not) informing the customer and just putting the most bent wheel on the right rear. That gets them out of the shop on their new rubber, and if they complain it'll be in 6000 miles after the rotation when the dud rim comes forward. 95% of customers do NOT want to hear that there's something else wrong with their car when buying several hundred dollars worth of rubber. The competition across the street can sell tires and keep quiet. Many drivers don't care, and many more think it's upsale hi-jinks, even if it's just sourcing another rim from the boneyard. Get the tires sold and out the door-- any problems can and will be taken care of afterwards via warranty.
 
The last two sets of tires I had mounted at Les Shwab (reputable NW chain), had to be rebalanced a week later (4/4 on one install and 3/4 on the other). One was a brand new set of Cooper, the other my Toyo Open Country just moving rims. I don't know whether they tend to settle after initial use somehow, or it was a sloppy person each time, but I've not had good success with reliable balance on the first pass. Another time, a tire change revealed a ball joint wearing. It was not apparent in the steering previously, but rapidly became apparent with new tires.
 
noticed my tire shop balancer spins real slow, always dead on even with all the weights inside.
 
Yes it is comnon, many tire shop will not do calibration until someone come back complaining. So if it is reputable tire and vibrate, the balancing machine typically is the culprit. Even more interesting, one batch of my tire is silen at 110 kmh bit vibrate badly at 130kmh. I thought a drive shaft issue but after rebalance at one of the shop that i complained before, the problem solves
 
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