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Discussion Starter #1
I've posted in a few other threads about some vibration I've been experiencing on my new 2015 s touring. Had it at the dealer yesterday and they road force balanced it. I did not get the print out, but they said the tires varied between .003 mn and .013 mn. Driving it after, the vibration has improved somewhat, especially at lower speeds, but it's still there at 75. The the harmonic is different now- it's a faster vibration that is over quicker, and there's a bit of a longer pause before it starts up again. I'm guessing its in the rear tires based on how I feel it in the seat. Feels like an up/down almost wheel hop vibration. It's not crazy strong, but at the same time, I've never had a car that felt like this. I'm thinking of taking it to a tire shop for a more in depth look.

Anyway, I've noticed that my tires have the red and yellow dots for balancing purposes, and there are two questions I have about them.

1) The red dots are not lined up at the valve stems on any of the wheels- could this be the source of my vibration?

2) on three of my tires, the red and yellow dots have a good bit of distance between them- anywhere between 6 inches and a foot or so. On my drivers side rear, the red and yellow dot are almost in the exact same place. Could this indicate a poor tire?

Thanks for any thoughts you all have.
 

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The yellow dot indicates the lightest part of the tire and should be matched with the valve stem (heaviest part of the rim). The red dot indicates the high spot of radial runout and can also be used to correctly mount the tire to the rim. Usually you align the yellow dot with the valve stem to minimize the amount of weight you need to add.

I had a vibration problem on my then new 1989 Civic Si hatchback that was finally solved by replacing the tires. The tires had excessive runout in them, but it took several times returning to Bridgestone to get the tires replaced.
 

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Discussion Starter #3
None of the dots on my tires line up with the stems. I've read that the red dot takes residence over the yellow dot if you have both for lining up with the stem, however.
 

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I have seen exactly zero new cars with the tire dots lined up correctly. I guess it's just quicker not to mount them the right way at the factory.
 

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Discussion Starter #5
LOL, thanks for the reply. If I'm still frustrated with the vibrations, do you think it would do any good to take them to an independent shop, have them line them up, and do the balancing again?
 

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Since the car is new, I'd work with the dealer and tire manufacturer before going to an independent. Be reasonable, but firm with your expectations. A brand new car should not exhibit vibration unless there is problem. Vibration can be caused by an out of balance situation, excessive run-out (out of round) or structural defect (e.g. belt delamination). You should be able to get this problem solved.
 

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Tire waranty claims can be tricky, especially if you simply have a flat spot on the tire, which can easily be attained by locking your tire during hard braking, yes it does happen despite having abs turned on

Do the following in order: tire pressure check, balance tire/see if there are no flat spots or bent rims while its turning on the balance machine
 

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Yes, the first step is to confirm balance. If the technician is good, road-force balancing is a pretty accurate way to do it.

Here's a low tech solution to detect excessive run-out:
Jack up the car and arrange a light source (or the sun) to cast a clear, sharp shadow of the contact surface of the tire on the ground. Place a piece of paper in the area of the shadow. Rotate the wheel and mark on the paper the extreme positions of the shadow. Measure that difference to determine if your wheel/tire combination is out of specification.

There are additional possibilities for vibration, including a variety of drive-train components, but the most likely source are the tires / rims.
 

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Bump. Did you ever figure this out? I had the same problem on one bridgestones. Even when they were 100 miles in, the same kind of vibration happened to me from about 71-76 mph. It drove me nuts. It felt like a flat spot. I figured I may have had a bent run but I hadn't gone to get them balanced somewhere else. Also they overinflated them at the time. I adjusted but same problem.
 

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All of mine have red dots lined up, but Roadforce corrected 1...remounted to its dictation. So far, I've always had great experience w/ that Hunter balancer to eliminate vibrations.
 
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