New tires and new 'wobble'
Last weekend we had the local tire shop replace our 8 year old tires (size 7.50R16) with a set of Cooper Discovery HT (235/85R16). Driving home from the tire shop (DiscountTire.com) it became imme...
Forum Discussion
Knownuthin,
Most Discount tire shop techs are fairly on the ball when it comes to analyzing tire/balance issues. They can get pretty technical when it comes to todays balancing. But, I don't care how technical they can and want to get if, you have one or more out of round tires, you can balance them every day for the rest of your life, AND THEY'RE STILL OUT OF ROUND. AN EGG IS AN EGG, PERIOD!
If tires are round, which, in motor home cases, getting perfectly round tires is less frequent than you would expect, then balancing is a no-brainer. It doesn't matter what technique you use, lead (now other metal since the planet hates lead), balancing beads, powders, rotating balls (as in Balance Masters) etc. Any of those methods will work, IF THE TIRES ARE ROUND!
So, here's the deal. Make sure the tires are inflated to the correct pressure and not low. Then, take the rig out and drive it for a good 15-20 minutes so that they are warm and, have no residual effect from sitting during the night. Then, upon return home, as soon as you can, raise the front end or, at least one tire at a time and place a gauge of some sort (could be two small 2x4 pieces nailed together with one standing up about 10-15" and, a nail protruding through it.
Now, place the tip of the nail very close to the outer tread(s) and then begin to spin that tire/wheel by hand and observe the deflection of the tire in close proximity to the tip of the nail. In other words, watch the variation of the distance that is created between the tread and the tip of the nail as you spin the tire.
Now, in the past, when I talked with several Discount Store Managers, a runout of more than .060 was declared an "unacceptable" tire and, it would be replaced. Anything more than that amount was an egg. So, you see, since tire manufacturers have been making tires since the Civil War, they pretty much know how to make them round. But, quality control does slip through the cracks every now and then and, a bad "batch" of tires will cruise right on down to the local tire store and be sold.
Now, the method for checking that I described above is a home procedure. Discount and any other tire store can do it right on the tire balancing machine much easier. Now, I'm not guaranteeing that this is your problem but, based on the fact that you have had multiple Discount tire stores "goof around" with your tires and they're still shaking/wobbling, and you don't mention that it ever happened prior to the tire change in the first place, than, I'd just about bet your house that it or "they" are out of round. Just a suggestion here. Good luck and please, please come back and post what you find out so that others will learn.
Scott
Most Discount tire shop techs are fairly on the ball when it comes to analyzing tire/balance issues. They can get pretty technical when it comes to todays balancing. But, I don't care how technical they can and want to get if, you have one or more out of round tires, you can balance them every day for the rest of your life, AND THEY'RE STILL OUT OF ROUND. AN EGG IS AN EGG, PERIOD!
If tires are round, which, in motor home cases, getting perfectly round tires is less frequent than you would expect, then balancing is a no-brainer. It doesn't matter what technique you use, lead (now other metal since the planet hates lead), balancing beads, powders, rotating balls (as in Balance Masters) etc. Any of those methods will work, IF THE TIRES ARE ROUND!
So, here's the deal. Make sure the tires are inflated to the correct pressure and not low. Then, take the rig out and drive it for a good 15-20 minutes so that they are warm and, have no residual effect from sitting during the night. Then, upon return home, as soon as you can, raise the front end or, at least one tire at a time and place a gauge of some sort (could be two small 2x4 pieces nailed together with one standing up about 10-15" and, a nail protruding through it.
Now, place the tip of the nail very close to the outer tread(s) and then begin to spin that tire/wheel by hand and observe the deflection of the tire in close proximity to the tip of the nail. In other words, watch the variation of the distance that is created between the tread and the tip of the nail as you spin the tire.
Now, in the past, when I talked with several Discount Store Managers, a runout of more than .060 was declared an "unacceptable" tire and, it would be replaced. Anything more than that amount was an egg. So, you see, since tire manufacturers have been making tires since the Civil War, they pretty much know how to make them round. But, quality control does slip through the cracks every now and then and, a bad "batch" of tires will cruise right on down to the local tire store and be sold.
Now, the method for checking that I described above is a home procedure. Discount and any other tire store can do it right on the tire balancing machine much easier. Now, I'm not guaranteeing that this is your problem but, based on the fact that you have had multiple Discount tire stores "goof around" with your tires and they're still shaking/wobbling, and you don't mention that it ever happened prior to the tire change in the first place, than, I'd just about bet your house that it or "they" are out of round. Just a suggestion here. Good luck and please, please come back and post what you find out so that others will learn.
Scott
