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Un-even tire wear

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Old Mar 20, 2007 | 05:54 PM
  #1  
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Un-even tire wear

I bet this has been covered somewhere, but the search thing won't ever load...

Anyways, I admit I spin and slide and do circle's in my 7, who doesn't?
But when I drive right and safe, this problem still happens.

On my rear tires, the outside (on both sides) is full of tread. But going towards the inside, it gets thinner and thinner.
Eventually, the outside is noticeably worn and the inside or my rear tires are barely showing the metal belts.
My front tires are fine though.

Well.. I asked people on a smaller forum about my problem and they said I should get a full alignment done.
They said I should do that, or get my rear wheel chambers adjusted.
So whenever I get new back tires mounted and balanced, I asked the guy about it.
He said I needed some kit, and that my whole rear end is f*ed up and all this other bull.

So, my real question is, do any of you guys have this problem and how did you fix it...

Thanks in advance,
-Brett
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Old Mar 20, 2007 | 06:30 PM
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If you are saying that the inside of the tread is wearing more than the outside, the problem is that you have too much negative camber on the rear wheels. That is, the top of the wheels are canted inward too much. Have the camber adjusted and/or replace worn out suspension components.
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Old Mar 20, 2007 | 06:38 PM
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From: North GA
Originally Posted by Go48
If you are saying that the inside of the tread is wearing more than the outside, the problem is that you have too much negative camber on the rear wheels. That is, the top of the wheels are canted inward too much. Have the camber adjusted and/or replace worn out suspension components.
so what... go to a tire shop and tell them to adjust the camber?
Because thats what I did and the guy told me I needed kits and a bunch of new rear end stuff

And exactly what suspension components? Thanks!
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Old Mar 20, 2007 | 07:03 PM
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you need to buy a camber kit to adjust the rear camber
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Old Mar 20, 2007 | 07:11 PM
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Originally Posted by pimpdaddy7835
so what... go to a tire shop and tell them to adjust the camber?
Because thats what I did and the guy told me I needed kits and a bunch of new rear end stuff

And exactly what suspension components? Thanks!
Yes, you need to get a rear camber adjuster. They are fairly cheap (~$100).

Is your car lowered? If not, it should be OK and this may be indicative of other suspension components that need replacing.
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Old Mar 20, 2007 | 07:17 PM
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I was wondering if he had lowered it also. With that kind of wear you definitly need a rear camber adjuster.
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Old Mar 20, 2007 | 08:43 PM
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ITS CALLED TIRE PRESSURE PEOPLE

WHEN YOU HAVE FUNN TREAD ON THE OUTSIDE AND NONE ON THE INSIDE..THAT MEANS YOUR TIRE PSI IS TOOO HIGH...WHEN YOU HAVE NONE ON THE OUTSIDE AND ALL ON THE INSIDE ITS TOO LOW..THINK ABOUT IT.
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Old Mar 20, 2007 | 09:01 PM
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no that wouldnt be tire pressure i thought so to but he said theoutside of both tires not the ousides of the tire meaning that the side facing the car is less worn than the side facing away from the car
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Old Mar 20, 2007 | 09:13 PM
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From: North GA
Originally Posted by DriftingB26RX7
ITS CALLED TIRE PRESSURE PEOPLE

WHEN YOU HAVE FUNN TREAD ON THE OUTSIDE AND NONE ON THE INSIDE..THAT MEANS YOUR TIRE PSI IS TOOO HIGH...WHEN YOU HAVE NONE ON THE OUTSIDE AND ALL ON THE INSIDE ITS TOO LOW..THINK ABOUT IT.
uhh.... hate to burst ur bubble... but my pressure's just fine thank you
45 psi... and I've deflated it and inflated it and it's still the same....

so i gotta buy the camber kit thing and I'll be all set?
and my 7 isn't lowered, and im pretty sure my shocks and all are good

so who sells those kits?
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Old Mar 20, 2007 | 09:15 PM
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The issue is as has been stated. CAMBER. It's likely that the struts and springs are worn out (as they were on my car which exibits the same issue). The worn components cause the ride height of the vehicle to be lower and in turn change the angle of the rear arms and obviously the tires that are connected to them. There is no factory adjustment for the rear wheel camber however there are several aftermarket kits you can buy that allow it to be adjusted. I went with Racing Beat's adjustable rear subframe link.

If it were over-inflated tires, that would cause excessive wear more in the CENTER of the tread pattern as the tires would basically be swollen up like ballooons.

*EDIT.. I think there may be some mis-communication here. The OP *I THINK* means "inside" = inboard side of tire toward car and "both sides" = both sides of car. NOT "inside" = middle of tire and "both sides" = both outboard sides of tire.

Please correct me if I'm wrong here.

I'd say you better start getting to work on that suspension!

Last edited by RoughRex; Mar 20, 2007 at 09:23 PM.
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Old Mar 20, 2007 | 10:16 PM
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ok, so it's your camber. are you still using stock struts? might wanna change them. and adjust the camber since lowering the car puts negative camber on. and 45 psi is too much for our lightweight cars. i recommend between 32 - 35 psi. dont follow whatever the tires says, that just says that is the MAXIMUM pressure that your tire can hold.
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Old Mar 21, 2007 | 06:39 AM
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Originally Posted by DriftingB26RX7
ITS CALLED TIRE PRESSURE PEOPLE

WHEN YOU HAVE FUNN TREAD ON THE OUTSIDE AND NONE ON THE INSIDE..THAT MEANS YOUR TIRE PSI IS TOOO HIGH...WHEN YOU HAVE NONE ON THE OUTSIDE AND ALL ON THE INSIDE ITS TOO LOW..THINK ABOUT IT.
WRONG dumbass.
Keep off the caps.

When your tire pressure is too high, the CENTER wears faster.
When your tire pressure is too low, the inside AND outside wear faster, leaving the center okay.

STOP GIVING WRONG ADVICE.

Unless your FC is dropped really low, it's actually toe in / toe out that is causing the bad rear tire wear.


-Ted
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Old Mar 21, 2007 | 08:55 AM
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As for asking about random advice on a forum like this, take it with a grain of salt. Some people, like DriftingRB26RX7 have no clue what they are talking about. Others, like RETed, have a vast wealth of knowledge (even though I dont always agree with him/like his statements) behind them. Take that into consideration. Me for example, I am currently in a tech school, and pretty much just learned about all this stuff, and aligned my car. I've seen badly worn tires because of toe, and camber, but that doesnt mean I'm a genius.

I would say however that your problem is either excessive negative camber, or excessive toe out. Get a 4 wheel alignment done, and make sure you have him print out a report of what your current alignment settings are. Before you run off and do that though, read the next part.

If your toe is really bad, as RETed suggests, run your hand over the tire toward the center of the car, and then back the other way. If you feel an edge, or something that tries to grab your hand, then toe could be the issue. If you dont have that edge however, or feel as though the tire has a "high spot" that grabs your hand on one side of a tread block or the other, toe is more than likely not your issue. Either way, a 4 wheel alignment will tell you what you need to do.

Start there.

Oh, and yes I do have a similar situation, but I did it intentionally to corner better. Im currently running about -.7 degrees camber in my Vette in the rear, and about -.5 in the front. Toe is perfect, and caster is set a little high to help keep it straight during accel/high speeds. And im glad to say that it worked It runs perfectly straight down the highway at 70, and will take corners about 2x the posted speed. It does however wear the tires exactly as youve said though, inside wears much faster than the outside, etc.

Good luck fixing your problem.
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Old Mar 21, 2007 | 09:06 PM
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I guess I didn't decribe my issue the best Take a look at my nice pic at the bottom.

Thats what I mean and it's like that on both rear tires...

And I barely notice a slant in the tires... like if I'm looking from the side. The top is father in and the bottom is kind of outwards... I guess this is what 'toe out' is?

Well whenever I get some extra money I'll get that alignment.
And I'll remember to get a sheet like Rotary Noob suggested

But.. can someone explain what the whole toe thing is? Sry... I'm young


Last edited by BrettLinton7; Mar 21, 2007 at 09:12 PM.
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Old Mar 21, 2007 | 09:35 PM
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http://www.familycar.com/Alignment.htm

You have too much negative camber and will need to fix your suspension and/or purchase a kit to make the rear camber adjustable.
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Old Mar 21, 2007 | 09:39 PM
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that took me about ten minutes to even understand what the hell i was looking at...and then i finaly realized you drew in the lights and the liscense plate
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Old Mar 22, 2007 | 06:20 AM
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Originally Posted by pimpdaddy7835
And I barely notice a slant in the tires... like if I'm looking from the side. The top is father in and the bottom is kind of outwards... I guess this is what 'toe out' is?
This actually sounds like (negative) camber.

Is the car dropped significantly?
You should be able to stuff at least THREE fingers in between the top of the tire and the bottom of the wheel well.

Toe-out is when the front of the tire points towards the outside more than the rear of the tire.


-Ted
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Old Mar 22, 2007 | 07:53 AM
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Yeah thats some serious camber. Thats what I thought as soon as i heard how your tires are wearing (since mine are the same...)

Yeah. Negative Camber is your issue.

Get a 4 wheel alignment, you may need to get camber plates or something similar to fix it.
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Old Mar 22, 2007 | 07:07 PM
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Ok... so a 4-wheel alignment and a camber adjustment kit, and I'm good to go? And the guys down at the tire shop'll be able to put that kit on right? And I took a pic, which you can kinda sorta see the 'slants'.





Yes, I've got 2 different rear tires
Anyways, you can atleast see the slant.

(And if you look towards the inside of the tire, you can slightly notice less detail in the tread pattern, like the second and third pic)

And I was thinking... would new rear shocks fix this? Because I was looking at the website Roughrex left and it had a drawing that gave me that impression







And... while I'm asking all these Questions, I've got another problem suspension related...
When I corner kind of tight, the whole car vibrates and shakes until I'm out of the curve. And when I go over the smallest bumps, I feel it. So what's causing this too? Shocks?
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Old Mar 22, 2007 | 08:59 PM
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Yes, worn struts and springs are what's causing these issues. I will also note that after replacing the struts and springs on my car the ride did get noticeably stiffer, however; once I replaced the front and rear sways with a set that matched the springs (both are eibach pro kit). The ride got quite a bit smoother. I'm betting this only occured because I used aftermarket struts and springs that were stiffer than the originals and the factory sways were not strong enough to work with the stiffer springs. If you decide to replace these items, there is a good chance that you will not need a camber adjuster but only if you buy springs that maintain the stock ride height... which I had a hard time finding.

Any reputible automotive shop should have no trouble installing the camber kit you choose.

As far as shaking around corners... I'm not real sure. Check the ball joints and tie rod ends for play. The only other thing I can think of is that you have a non LSD rear end and you are dragging the outside rear tire around the corner... but I would expect that vibration would be minimal in that situation. Also, check your wheel bearings. Jack the car up and put it on stands. Then grab each wheel and try to move it around, yank on it etc. If it wobbles or moves in and out a little you will need to replace the bearing.

Last edited by RoughRex; Mar 22, 2007 at 09:08 PM.
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Old Mar 22, 2007 | 10:01 PM
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This happened yesterday because I lowered the car and did not adjust the camber!


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Old Mar 23, 2007 | 03:44 PM
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Yeah, if I were you, I would buy a camber kit, new shocks, new springs, and the same tires for each side. Tires can make a difference on how well it will be aligned when you are done. Even if the tech does a perfect job on the angles, the tires may be different enough that they cause a pull.
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Old Mar 23, 2007 | 04:31 PM
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actually that happened cuz you didnt check you're tires and let the inside edge get too low. the cause of the wear was bad camber but the cause of your tire blowing out was laziness on maintaining your car.

i work at a tire shop. as everyone has said, its negative camber. replace the worn out stuff and get a 4wheel allignment and that should fix your problem. if its all stock stuff you dont need a camber kit, you only need that if you lower your car (but if you're gonna replace the springs anyways might as well get lower ones, for a smooth riding street car eibach pro kit would be my recommendation, lowers your car about an inch, little bit stiffer ride and definately tighter handling.)
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Old Mar 23, 2007 | 05:47 PM
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There is a lot of wrong information that is being said. You do not get any camber change with worn struts, only worn springs. struts only dampan the up and down movment and do nothing to hold the car up.
also you may want to check that nothing is bent. I don't think it will be since both tires are wearing out the same.
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Old Mar 23, 2007 | 08:37 PM
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anyone sugest rotating your tires more often?
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