Abnormal tire wear?
 

I'm somewhat new to RWD cars so please bear with me. I JUST passed 10000 miles today (I know, sad day) and I've been noticing a weird wear pattern on my rear tires (still running stock tires). The outsides seem to be wearing faster than the inside. I can tell visually that the rears have negative camber (which I'm assuming is normal) so I'm kind of stumped as to how the outsides are wearing prematurely. I know if the toe was off combined with the camber, there would be some feathering on the inside right? I'm a little confused. Also, I've had bad luck with alignment shops knowing all the geometry involved in alignments, so I'm looking for a bit of education.

Thanks guys (and girls)

Overinflated tires wear from the outside more than the inside. I have 6k on my tires, and mine are wearing pretty even. Make sure the air pressure is correct

I thought that over pressure would cause that on the inside and outside? or does the camber some how keep the insides from wearing?

Try here for further info. to much camber will affect the inside wear if you have a little to much neg, and vice versa.
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Trip, I believe you have it backwards. Too much air causes the inside to wear more. When having too much air, rather than having a "flat" surface to ride on, there is more of a rounded shape and the tire will ride on the highest point. i.e. inside (center) of tire.

OP. Just to make sure we're all talking about the same thing. When you say "inside" do you mean the middle of the tire or inside as in closest to the car? Since you said "outsides", I'm assuming that by "inside" you mean the middle of the tire.

I think there is an outside, middle and inside. My outsides are wearing too quickly. You are right, too much air causes the center of the tire to wear quickly, while too little causes the insides and outsides...

Another example would be that camber typically wears out the inside of the tire.

Those Nissan bugs are still on the prowl!

The camber "issue" isn't really a bug. The negative camber makes for better handling. Makes for more tire wear in the process.

Right, but negative camber should wear the insides of the tires faster than the outsides, and I have the opposite and as I mentioned previously, if it were a toe issue, then I'd be getting feathering on the outside (which I'm not). Aside from having positive camber on a tire, I can't think fo anything that would cause only the outside to wear faster than the rest of the tire.

Anyone know if it is just the compound of the stock tires? These days there might be different materials on different ribs of the tire... If this is just my driving habits (which is not aggressive), I'm ok with that (kind of) but if there is something I'm not thinking of, I'm all ears.

Yeah, I was just speaking to j.arnaldo's comment.

I'll have to check mine when I go outside, but I vaguely remember the numbers on mine being a little weird also. It wasn't really enough to worry about when I checked it. Kind of attributed it to a heavy right foot. :rolleyes:

Have you actually used a depth gauge or are you just eye-balling it?

Thanks for correcting me. Dam dyslexia :roflpuke2:

How about some pics so we know if it's abnormal or not.

I'll work on that...


Thats the old mark 1 eyeball... its enough to notice visually... I'll try and get some pics

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Heres some pics... this is the drivers rear tire... so the left of the photo is the outside of the photo.

Mainly what I see is the depth in the groove to the far left compared to the other vertical grooves. Looks and feels shallower.

I see that the outside inner is wearing out quicker. The wear doesn't seem to abnormal to me. If your cold air pressure is 35 then I would get an alignment, about $90.

Thats what I was thinking too... at least someone else can see it too! :tup:

The tech said the wear looked normal... its an optical illusion due to tread design. apparently, depth is good and there is no feathering or anything. PLUS I couldn't get an alignment anyway due to the fact that they don't have the updated software for the alignment machine that includes the 370Z. You'd think Nissan would get those out before one ever hit the showroom floor... I mean the car has been out for 2 years now

I was thinking the same thing a few days ago. When I hit 15k I figured I'd better check my tires. Outside seems more worn than inside/middle.

Before I go out for the day I'll check tire pressure and take a few pics and show depth of wear.

Thought I'd weigh in with my results.

Mine are wearing EXACTLY the same as Volcom370z's are. Got 6,700 miles on them, tire pressure is 38 psi. Measurements taken from outside to inside - in 32nds:

the front treads measure: 5,8,8,8.

The rear treads measure: 5,7,7,8 (maybe should drop these to 35 psi?)

I think the wear is good considering both front and rear are wearing the same and evenly, and the Z handles great.

But if I remember correctly, in New York, once any tread reaches 3/32, the tire won't pass inspection, even though most of the tire has a good 6/32 of tread depth left. I don't know this for sure, because I always replace well before 3/32 anyway on any car I drive. Being safe is non-negotiable for me.

However, especially with such wide tires, 4/32 or 5/32, especially on a car like the Z, could be dangerous on wet roads, so for a 1 or 2/32 loss of tire life, I'm not complaining.

I went into the Z knowing I'd be buying lot's of tires!

If anything you should raise pressure even more right? Over pressure should wear the centers of the tire more and underpressure the outsides. I do notice that i'm getting an even contact patch and i'm not getting any abnormal wear. a couple of things i've been thinking is that maybe the outsidesof our factory tires don't have as deep of tread as the rest of the tire? not sure where that is measured by the factory. secondly, there are tires on the market that have different compunds on different ribs of the tire, maybe we have a bit softer compund on ours?

It sounds so crazy that that would be true, but I wondered the same thing myself!

When I replace I'm planing to move up to a better tire, and I'll do my research then for the selection. I will check the tread depths on the next set just for the heck of it, just to see if they're all the same, but whatever they are, they are.

To me, with the Z it's all about handling, not how many miles the tires deliver.

Used to be that all tires were around 11/32 each tread depth, don't know about these type of tires.

I do have to say that for OE tires, these Bridgestone's do a really great job on the road. Can't really say anything bad about them. In fact, I really like them. Very pleased with them. Seems like I should move up for my next set, and I most likely will, but I don't know, these have been great tires so far.

I completely agree with you. I have no complaints about these tires despite the treadwear rating. Im thinking my next set is going to be PS2s... if all the production supercars (aside from the GTR) can run them, they are FAR good enough for the Z.

I just checked my tires and I see the outer is wearing more quickly than the rest. I still have more tread than op. I'm been lowered for almost 11k miles, been lowered 8k with h&r.

All this just means you guys like to corner more than you like to drive in a straight line.:tup:

I like it! :tup:

I think what it is though, is the outer groove in our tires has less depth than the inner grooves

It does look like that now that you say it.

Thanks... but why? I'm pretty sure that doesn't answer the issue at hand. The only thing that causes more wear on the outside of a tire would be positive camber, which my car definitely doesn't have.

Your welcome! "Why, because I tried to help you". Your first sentence tells me you did not look over the site. Your second sentence, is "contradicting", for the problem you are experiencing. In the future, I will save my time, instead of offering assistance to you!

I meant no disrespect, but I spent quite a bit of time on Tire Rack before actually posting my original posting. I also when to my dealership. I do appreciate your help, but a page full of links is kind of vague in that I didn't know what exactly you were referencing.

Hmm... I've had my Hankooks for about 1.5 years, and the inside rear (1") is nearly bald. I put in 34 PSI year round.

If that site didn't have the answer, then your car has a unique problem(manufacture defect, possible, but I doubt that).
Do both rear tires have abnormal wear?

I doubt it too. I can visibly see the negative camber in my rear wheels, yet it seems that the outer most rib of my stock sport tires wears out faster that the insides. It should be the other way around. I've also checked with my local dealer and was told the wear of normal.

My conclusion is that the outer groove of the sport tires isn't as deep as the others which seemed more likely to be the problem.