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Discussion Starter · #1 ·
For quite a while, I have noticed that I have some vibration in the front left of my car. I tend to get more noticable vibration when going slow, and then it seems to go away or else the frequency gets to a point where it isn't as noticable. For instance, when I slow down, there is a distinct whump-whump-whump from the front left.

Well I noticed that recently, I am losing tire pressure pretty rapidly from that wheel, maybe 5-7psi every few days. With a lot going on, I have just been putting air in it, and looked to diagnose it soon.

Well today I pulled off the wheel assuming a simple patch job, and unfortunately could not come up with a nail or any other debris in the tire. Upon closer inspection, I noticed that the tread on the inside was really messed up. Basically one part of the tread is higher, then lower, then higher, then lower, etc. Seeming to indicate that the tire is "wobbling" when rotating.

So now I am wondering if the tire is warped, or if I even have a broken suspension piece.

Any ideas on how to diagnose this a little bit better. I dread this, because it's obviously something I am going to need outside assistance on, especially a bent rim, so I am hoping to have some idea of what is going on to make the fleecing by wherever I take it a little bit less.

I had planned to get some new tires for it in the next few weeks or so, so the tire wear thing is no big deal, but of course I need to sort this out before new tires are put on...this kinda puts a crink in things.
 

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We know that the tire is shot, but why ??
Probably the rim needs to be restored as well....One too many potholes will do this..And these very low profile tires do not help...
Jack up the car enough for the tire/wheel to clear, then spin this assembly with a dial indicator set against the rim. This should determine if the wheel is running true or not...
Examine the front end pieces, particularly the rubber bushings.
But, the fact that the tire is losing air pressure tells me that it is not seated well to the rim. A bush with some soapy water can easily bear this out...
 

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Discussion Starter · #4 ·
Thinking of heading to discount tire, and have them check it out, since I am going to buy tires from them anyway. Their price is only slightly more than if I bought tires online and then had them installed somewhere anyhow.

Since having a look, it appears the tire on the other side is like that as well.
 

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If the tire has a wear pattern that repeats around its edge, it may be cupping which is caused by suspension wear - struts etc. If, however, each block of tread is angled the same way; this is feathering which can be fixed by alignment correction. If it is not too bad it may be possible to put them on the rear.
 

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Discussion Starter · #6 ·
Ok, I just checked, and all 4 tires seem to have the same type of wear. It really is very strange.

Here is an image to give you an idea of how the wear is. It is just on the inside part of the tire, the rest looks normal. And really, unless you feel the tread and look closely, you would not notice anything abnormal.

The tires are those dayton daytona's or whatever, which I think were OEM for the car, but of course this was a second set. I got them with the car originally at 55k and the car now has 92k. I am wondering if it is just something weird with the tire. If it was something with the suspension, I would expect the wear to be greater on the inside, but fairly even, not "bouncing" exactly on the same tread spot over and over and over again in such a uniform pattern.

 

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That's scallopping, and it's a classic sign of misalignment.


Without researching, I can't remember whether it's a toe issue, or camber.
 

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Discussion Starter · #8 · (Edited)
Google searches seem useless, as some say that is Scalloping, some say it's Chopping, and some say it's a sign of worn out suspension parts, and some say it's misalignment or poor rotation intervals.

I am taking it in Monday to have tires put on, and I hope they can tell me whether it's a suspension issue or what not.

I guess my suspension parts may be worn as well, as they now have 92k miles on them.

I just checked the rear suspension and it seems ok with the simple push down test. If I push down hard from the trunk, it just bounces back up and does not continue to bounce. I don't really know how to test the front though, but when I go over things like speed bumps, I still her "whoosh whoosh" not a bang of any sort, if that means anything. The rear could be out of alignment though from the trip 1.5 years ago when I moved, the car was pretty loaded down, and I drove about 1500 miles that way.
 

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I had a similar wear pattern and it was diagnosed by the tire shop as feathering. One sympton is that the wheels would go out of balance after a few months due to the uneven wear. They corrected the front alignment and the problem has not reoccured.
 

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Discussion Starter · #10 ·
My plan will be to get the new tires on, have an alignment done, and then check the wear pattern after a few thousand miles and go from there.
 

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Discussion Starter · #11 ·
I got new tires today, and it has improved a little bit. THe ride is quiet again, but likely due to the fact that the tread is not worn yet. I still notice some vibration in the steering wheel, but the vibrations at low speed and the slight "wobbling" of the wheel when braking is gone.

I guess I will have a full alignment done, and see if that fixes the issue, if not, I will have to start looking at suspension issues.
 
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