Bent Rim?


#1

On a recent trip our, a 2007 Mazda 3 with 63,000 miles on it developed a vibration in the steering wheel. Sometimes we could feel a vibration in the floor too. And there is a noise very similar to what tires make when they have a lot of irregular wear on them. I would say it came on suddenly. I did not hit anything.

The front shock were replaced about 3 months ago. We got new tires about 6 weeks ago.( And it was like a new car again .) These tires were not cheap and we did not get them at one of those discount stores. The tires are low profile, the rims are nothing special- just what came on the car.

I took the car back to the place I had purchased the tires. They told me one of the rims was bent. They had put 3.5 ounces of weights and it still wobbled. My regular mechanic advised me to get the tires rotated first to see if the problem went away and to get a second opinion about the rim, so I did. The vibration problem seemed to go away after the tires were rotated, but the tire noise was still there.

Next I went to the place always go to for alignments. They checked the suspect wheel and said they could not "see’ that it was bent. They too put 3.5 ounce of weights on it, thirteen little square weights. Now the suspect rim is on the driver’s side rear instead of the driver’s side front. And the vibration is back.( And my car feels like an old clunker.)

What should I do?

Thanks to all who offer an opinion.


#2

Just offhand this sounds like the possibility of a bad tire. That’s a lot of weight (3.5 ounces) needed to bring a tire into balance and anytime I’ve ever mounted and balanced a tire something like that would have gotten my attention.

Tires generally have a tiny red and yellow dot on them to aid in mounting. One of those dots should be aligned with the valve stem. Have you looked closely to see if that dot is matched with the stem?

I will add that a defective tire can cause a noise and that a visual inspection of a tire or the rim may not reveal anything. However, a bent rim should be noticeable when the wheel assembly is spun up on the balancer. Hope that helps.


#3

Ditto to everything OK4450 explained. The protocol described by him in his second paragraph is a process known as “indexing”, which should be done with all low profile tires that have such manufacturer’s index dots on them, but many tire guys are too lazy or lack adequate training.

Regarding the internal damage, there is a type of balancing called “road force balancing” that spins the tire with a simulated road force by pressing a spinning drum against the tread while balancing. This can detect internal damage that a normal spin balancer cannot. It the tire store has such a machine, have them check it that way.

In summary, check for indexing and have a road force balancing performed and the tire replaced if defective. That should smooth out the ride.


#4

You need to keep after the place you bought these tires. As OK said, if it’s a ‘bent rim’ they should be able to show you easily by rotating the wheel and seeing it wobble. Adding 3.5 ounces is very high, more like a bad tire. How many ounces on each of the other tires?


#5

Did you change tire size? You mention low profile tires, did this vehicle come with low profile tires?


#6

What concerns me is that the problem came on quite suddenly - and apparently not when the tires were changed.

I’m wondering if we are talking about a CV joint - but I can’t discount the possibility that the rim is indeed bent - that might explain the amount of weight to balance.


#7

Capri, that’s an excellent point about the CV joint. I discounted a bent rim because a bent rim is so easy to see on a machine and he/she stated that the second shop couldn’t verify it. But we won’t really know until we know.

My money’s on a defective or damaged tire.


#8

Thanks for all the input. I suspect it is nothing more than a defective tire. I have one tire with no weights at all, one with 8 and one with 9. That doesn’t sound right to me. I have had some experience with bad cv joints. The boot is not cracked and I do not hear any strange noises like the other cv joints made.

I am going to my son’s wedding this weekend an will have to deal with this later.

Thanks again for your input.


#9

A bad inner CV joint can cause a vibration or wobble, normally at a specific speed. All the ones I have experienced have felt like a rotational wobble and could be felt throughout the vehicle, and they don’t normally make noise. The popping sound often associated with a bad CV joint is the outer joint, which goes bad much more frequently than inner joints.


#10

Sounds like you have a tire with a broken belt or the tire is out of round. I remember my dad buying a set of tires probably back in the '70’s, the car wasn’t handling right and had a bad vibration, he took it back to the store where the tires were bought and they confirmed he had a tire that was out of round. They replaced the tire and the problem was solved. Usually a tire with a broken belt will have very abnormal wear patterns. The tire may look new in one location and be and be worn or cupped out in another location.