Help me diagnose road noise

mazda
protege
vibration
noises

#1

I have a 2003 Mazda Protege with 120,000 miles on it. It recently started making a noise between 30 and 45 mph that sounds and feels like vibration. Above 45mph (ie. interstate), the noise seems to dampen a bit, but it is definately still present. It makes virtually no noise below 25mph. There is no ‘wobble’ or deviation of steering. Engine speed doesn’t matter - I put it in neutral and rev to 6000 and it sounds fine. It usually makes the noise while coasting as well, as long as I’m between around 30-45mph. It may be coming from only the front right wheel, but its a little hard to tell since I’m always in the drivers seat. I jacked up the car and the wheel had no lateral or horizontal wiggle motion as would be expected with bad bearings. Hmmm… I think thats it, thanks alot for your help! Let me know if you need any more info!


#2

You MAY have a tire separation causing the vibration.

From your post it would seem the vibration would be from the drivetrain/tires/wheel bearings/suspension, etc.


#3

Worn tires can generate a lot of road rumble. If you have tires that are into the tread wear indicators (or close), I would replace them before spending a lot of time looking for problems elsewhere.


#4

First step might be to swap the tires front to back and see if the noise moves. if it does, you have a tire problem, not a suspension problem. That’s good news, tires are usually cheaper than suspension parts.

If you don’t have a torque wrench, buy the cheapest one you can find and use it to make sure the lug nuts aren’t too improperly torqued when you move the wheels. Too loose and the nuts might come off. Too tight and the disk rotors may warp.


#5

Thanks alot guys! One more note, the noise/vibration definately goes away when I turn to the right. I have to be going ~30-45mph and, coasting, as I enter a R turn it goes away completely. Does this give a clue at all?
Thanks!
Matt


#6

What type tires are on the car and how much tread is left on them?

I have tires on my Acura that are nearing the wear indicators (evenly worn, no cupping, directional tread) and they are VERY loud at 35-45 mph. Don’t know why that particular speed range makes so much noise, but below 35 they are quiet and above 45 they are less noisy.

When the tires had more tread they were not noisy. It’s only been the last year or so, as they’ve gotten to about the 3/4 point in their life, that they’ve become so noisy.

When I’m accelerating, coasting, turning, etc, the noise varies, but it is still loudest in this speed range.

What you’re hearing may be your tires.


#7

Mcparadise may be correct on the tires.

But the disappearance when turning right thing on top of the general description really leads me to say to worry about the pass side wheel bearing.

I recently originated this post b/c I too failed to find any kind of normal signs of a bad bearing - other than the noise:
http://community.cartalk.com/posts/list/2123091.page


#8

You’re describing a bad wheel bearing.

A bad wheel bearing can make noise, but not indicate that it’s worn from the wiggle test at the tire. Try this. Raise the vehicle so the tire is off the ground. Place your hand on the strut spring. Now rotate the tire slowly. If the bearing is rough, it sometimes can be felt on the strut spring.

Tester