Tire Noise: Options

[gathermewool]

I have Toyo Proxie 245/40R18s on my car right now. I rotated the tires front to back (directional tires) and immediatley noticed a few things:

1. At speeds
2. There's another, higher pitched resonance at around 30 MPH, which will go away as I speed up. The noise goes away above 30 MPH, but comes back again at around 60 MPH. From 60 MPH on up, I hear the same higher-frequency tire noise.

I swapped the left-side tires back and the low-speed, vibrating hum has gone away completely. I haven't been on the highway yet, but the resonant, higher-pitched tire noise at 30 MPH is there, but quieter and now sounds like it's coming from the back.

The tires were last rotated ~5kmi ago.


I inspected both the front and rear left-side tires and nothing jumped out at me. The sidewalls looked perfect, no feathering of the tread and no dents, bubbles or anything other obvious signs of a damaged tire. The tires all have ~ 7/32 tread left, FWIW.

My question is, what is this noise and might it require replacing that tire? I have a Subie, so that would mean buying a new tire AND having it shaved down to 7/32 to match the other tires.

Thanks for your input, guys. Wasn't sure if this should be in the Tires section or maintenance section. I apologize ahead of time if it's in the wrong section.

 

[dparm]

Have the wheels been balanced?

Performance tires are inherently more noisy, BTW. And STIs are not exactly revered for their outstanding quiet rides. I run the same size tire on my Audi S4 and they are loud.

I would take it to Discount Tire and explain the problem. Let them take a look.

 

[d00df00d]

Your front and rear alignments are different, which causes the wear patterns on your front and rear tires to be different. When you swap the tires front-to-back, that creates a mismatch between alignments and tread patterns, and you can get noise. I would bet that's what's happening in your case. The fact that it's happening more on one side than the other could be because your car's left/right weight distribution is different, small variations in tire construction, etc.

My advice would be to put them in the lowest-noise configuration, wear them down all the way, and then try to get some nicer tires next time. I don't think there's any real problem you need to worry about right now.

 

[Papa Bear]

Time for an alignment (and probably new tires if you want quiet).

Start reading at 07/26/10

 

[brandini]

My guess: 1 of 2 things:

Alignment, take it to a shop that prints before and afters.

Wheel balance, only take it to a shop that does Roadforce balancing. I have a Miata and turning 1 tire 180 degrees on the wheel solved an annoying road vibration I had that was caused by the most out-of-roud tire being on the most out-of-round wheel (the machine measures this). You index the high part on the tire to the low part on the wheel and re-balance and voila! Also the machine told you which tire to put on which corner when the process was finished. It's the only way I'll ever get tires balanced again.

 

[dparm]

Also, what kind of tires are these? OEM Dunlops?

 

[gathermewool]

To answer some questions:

The tires were rotated and balanced ~ 8kmi ago.

The tires were aligned 7kmi ago - -1 deg camber up front L/R, zero toe all around.

Tread depth was measure with the tires off, and all four measure at 7/32 on the inside and out. Two tires measure 8/32 in the center and the other to measure 7/32. Again, there didn't seem to be any unusual wear patterns.

32kmi on Toyo Proxies 245/40R18 - I've read that these tend to get pretty noisy as they wear, but only the one tire is abnoxiously loud (even for an STI

) Trust me, I didn't buy this car for it's quietness. While roaring down the highway, the passenger must to turn toward me or speak way up to be heard, and vice versa. It's not terribly loud, just the-econo-box-on-steroids-that-it-is loud. Haha

FWIW, there is balancing weight residue from a strip of about 5 stick-on weights that I saw on the "good" wheel that was not making noise. The dealer did the last/only balancing, so I asked whether they usually clean up the wheel after removing weights during balancing, and he said yes. With this "good" tire swapped back to the front, there is no vibration at all, which leads me to believe that is in fact just some leftover residue. The only noise now seems to be coming from the "bad" tire I swapped it with (now in the rear.) Just this swap has cut down the low speed, low frequency vibration to zero, and the resonant, higher-pitched sound to maybe 1/10 of what it was.

I'll ask the Subie dealership how they balance tires, since they're who I went to for the only time these wheels have been balanced. I'll make sure to have it roadforce balanced, too. IIRC, the tech when last these wheels were balanced mentioned that the machine told him how to rotate the tires; something about putting the most unbalanced tires in the rear. He didn't mention anything about physically aligning the tire to the wheel, though.

 

[dparm]

I'd suggest going elsewhere for the balancing unless you have a warranty.

 

[gathermewool]

Originally Posted By: dparm
I'd suggest going elsewhere for the balancing unless you have a warranty.


Is your comment based on the residue left or because you're thinking that I DID have a strip of weights fly off?

 

[CapriRacer]

First, you have generated irregular wear on your tires and that is the source of the noise. Eventually you will get a noticeable vibration.

Let's see if your post has any indications of where the problem might (and therefore what should be done to fix it!)

Originally Posted By: gathermewool
......The tires were aligned 7kmi ago - -1 deg camber up front L/R......


First problem - any camber approaching a degree could generate irregular wear. So what was the alignment like BEFORE you had it aligned?

Originally Posted By: gathermewool
......Tread depth was measured with the tires off, and all four measure at 7/32 on the inside and out. Two tires measure 8/32 in the center and the other to measure 7/32. Again, there didn't seem to be any unusual wear patterns.......


Any time you can measure a difference across the face of the tread (unless the tire started with a difference), you have a problem. The fact that you can't SEE a wear pattern, doesn't mean it is not there.

Originally Posted By: gathermewool
......32kmi........


That means the car went 25km before you got an alignment. What made you decide you needed one? A pull? (Sure sign there is a problem)

Originally Posted By: gathermewool
......on Toyo Proxies 245/40R18 - I've read that these tend to get pretty noisy as they wear.....


Some tires are more susceptible to irregular wear than others, but it's mis-alignment that drives the wear pattern. Even the worst tires will wear well if the alignment is good enough.

Originally Posted By: gathermewool
...... but only the one tire is abnoxiously loud.....


I'll bet that that tire was where the alignment was bad.

Originally Posted By: gathermewool
...... With this "good" tire swapped back to the front, there is no vibration at all, which leads me to believe that is in fact just some leftover residue........


No, the residue is so light it has no affect on the balance - certainly not enough to cause a noise problem. It's unsightly, but will have no affect on things!

Originally Posted By: gathermewool
...... The only noise now seems to be coming from the "bad" tire I swapped it with (now in the rear.)......


OK, but here's the problem. You've rotated the tire OUT of the position where it was generating the wear pattern - and experienced the noise - then rotated it back. You need to put the tire in a position so it generates a different wear pattern. Unfortunately, while it generates this new pattern, you'll be getting noise, but that will gradually go away as the new wear pattern developes. If you don't, the wear pattern will get worse - and these things tend to accelerate. Put another way, once a wear pattern starts, it wants to keep going.

Originally Posted By: gathermewool
......I'll ask the Subie dealership how they balance tires, since they're who I went to for the only time these wheels have been balanced. I'll make sure to have it roadforce balanced, too. IIRC, the tech when last these wheels were balanced mentioned that the machine told him how to rotate the tires;.....


Yup, the tech was reading the road force - so there is no reason to quiz the dealer.

In conclusion, you need to rotate the tire back and tolerate the noise for a while. The alternative is to get a new tire - and all the problems associated with that!

 

[gathermewool]

Alignment/Balance:

The wheels were first aligned when I had the tires installed back in 12/08 at Townfair Tire. I've been running -1deg of camber and zero toe all around since the tires were new. For me, the performance gain is well worth the slight increase in wear during normal driving. Besides, the way the STI suspension geometry works, I gain camber during aggressive turn-in, so the negative camber adds a good bit of grip while driving aggressively. I haven't tracked the car yet, and can honestly say that I haven't come close to pushing this car to it's limit on the street, so a little less negative camber might be doable in my situation. It sure does feel good, though!

I had the wheels aligned after installing stiffer springs. The drop was only 5mm (4”,) but I wasn't sure if I'd properly aligned the camber bolts after install. Turns out the toe was only off by a couple of tenths, but the right camber was closer to zero while the left was closer to -1 deg. I actually forgot to draw in my sten. pad what the camber bolt looked like on the passenger side!

No noticeable pull or anything else.

The previous balance was because I thought I felt a vibration in the rear. I drive through Boston and NYC on occasion, and occasionally can't slow down in time or swerve to miss pot holes, and some were so bad it made my cry a little on the inside. I inspect for the gross and obvious every oil change, but wanted to have another set of eyes (human and Road Force) check things over to make sure everything was SAT. Subaru does in fact use a Road Force, and only one wheel required ¼ oz. to be added, so it seems that they were pretty well balanced. I was going off memory in my earlier post about what the tech said (I don't think he'd remember, even if I did ask.) My question to the dealer was only if the residue was just residue from the last balancing or if, since they ALWAYS clean up the residue (not saying they do or don't; just a general statement,) its presence means that weights have definitely fallen off. The fact that my steering wheel has no vibration with the offending wheel in the front leads me to believe it's just some leftover gunk.

Wear:

I just grabbed my sten pad and realized I incorrectly stated that only two tires wore less in the middle. All four tires measured 7/32” on the inside and outside. Only the front right tire measured 7/32” in the middle; all three others measured 8/32” in the middle.

The question of the day is whether it's an unusual wear pattern that can be corrected after a thousand or two noise miles or is it due to damage. FWIW, I drove to Boston and back and the noise did not change at all. That's only a couple of hundred, but I assumed that the tires would have quieted down at least a little. I don't mind the noise if it's normal and will go away eventually (or at least quiet down,) but if it's permanent, something else will have to be done.

Conclusion:

Bah! Noise is ok for a bit, and if it was only the vvvv...vvvv...vvvv low-speed vibration/hum, there'd be no problem. But, the anything-over-60mph higher-frequency hum would make me want to poke out my ear drums if I had to deal with it for another 5/32”! haha

I'm not sure that it would really be worth spending the money on a new tire only to shave it down, and buying four all new tires seems foolish. These tires have been wearing pretty evenly so far, irrespective of tire rotations, so I think, worst case, I'll leave the loud tire on the rear if it doesn't quiet down and maybe have to replace the tires a little sooner than usually. Heck, if I get 40kmi on high performance AS tires I should be happy. The summer tires/wheels I'll be running this spring...I'll be lucky if I can get half that!

Thanks for your insight, I appreciate it!