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Highway Noise....?

4K views 8 replies 5 participants last post by  mrchuck 
#1 ·
Hello all,

Posting to ask for input on an issue with my '05 SS/SC. I've started noticing a droning sound, much like tire noise. It started showing up only at highway speed, 60 mph and above, but gradually became louder and more noticeable at lower speed, to the point where now the drone is as loud at about 45 mph as it used to be at 70. I have 30k miles (47k km) on the car, with original Pirellis and stock rims.

At first I thought tire noise, but the sound is the same regardless of the type or quality of pavement surface; interstate concrete to 2-lane blacktop, wet or dry, warm or cool, makes no difference at all. Higher speed means more noise, lower speed means less.

Am I just misidentifying tire noise arising from normal wear, or is something else going on here, like rear wheel bearings needing r&r or repacking? Or are my ears fooling me, and is the sound actually originating from the front-end?

Any help you can provide will be greatly appreciated.

Thanks!
 
#2 ·
you must not puch your car at all, I have a little over 10,000 on my tires and they are almost to teh wear bars. But Im pretty sure your due up for a set of tires and that is def. tire noise.
 
#3 ·
Thanks for the post, suprchged.

Tomorrow, I'll get out my digital vernier/depth gauge and get an accurate reading on tread depth, front/rear, and post the results, probably with pics. I am pretty easy on the car, at least from a dead stop. Mainly highway miles.

So I can't really hope to get more than 30 k miles from Pirellis? Bummer.
 
#7 ·
the UTQC rating of these tires i think are around 300 so around 10-15,000 miles is acceptable. I personally am not going back to the stockers for the fact they SUCK. Im getting the KDW's NT by BFG they grip better and have better wet traction.:)
 
#4 ·
Thats crazy 30 thousand on stock! I am impressed! Hey have you ever rotated them? If so did you move the front driver side to the back driver side (what you are suppost to do).
Some places will do the old fasion way and rotate them across. This ruins the bands in your tires and it makes them real loud.
 
#5 ·
Where the Rubber Meets the Road....

As promised, here is the tread depth/tire condition update:

Both front tires read out with a tread depth of 4.4mm or .1795". The rears are not quite so perfectly matched, but do read a little deeper at 4.71/.1865 L, and 4.74/.1875 R. All measurements are taken in the outermost tread groove.



As you can see in the photos, the wear is pretty even, and there is still some room before the wear bars will be touching pavement.







Being the factory rubber, they have only been rotated once.

This afternoon, I put in a call to the dealer, where I had the tires rotated at the same time as an oil change. That was almost 20 000 km (12 k miles) ago. I asked about the precedure for tire rotation; crisscross pattern, or straight front-to-back, and before I had finished asking, the service guy interrupted and told me they never cross sides, because it can cause the belts to shift and ruin the tires!

So, you anticipated the answer very well, Klugster. In fact, many years ago, my dad taught me about this, saying that in the old days, with bias-ply tires, it didn't matter which way you swapped them around. They even used to advise swapping the spare into the rotation to extend the life of all five; an idea from the days of full-sized spares, naturally (I know this stuff because I'm OLD). However, said Dad, with radials, if they've been run any distance, changing sides, and reversing the rotation can actually make them fall apart.

Personally, I still have a sneaking suspicion it's bad bearings, either front or rear. Noticably warm wheel centers on the rear (but not the front) after 20 minutes of highway travel just tends to confirm this idea. I guess time, and miles, will tell the tale.......

Steve S.
 
#6 ·
I just measured my new '07 SS Perelli's and the 4 tires nominal depth is accurately .300 + or - .020. I think you did good with your pair of tires. You have trvelled an average 15k per year all highway miles. If you have good lube in caliper pin slides, lotsa pad left in your brakes, I'd buy some new tires, and save the old ones for the poor weather/season.
 
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