Off road tire noise

[stevie s]

Hope someone can shed light on this.

I have an 05 CTT with 67K miles on it. I am hearing a noise that sounds very much like the noise that is made by off road tires on pavement. It seems to be coming from the front passenger's side. It slows down when I lift off and the pitch increases when I step on the gas. It starts as soon as the car starts moving and the pitch changes with speed. It never goes away.

I am running Falken tires and am suspecting it is indeed just tire noise but am not sure how to narrow it down to tires. They came with the car when I bought it a couple of months ago so I have nothing to compare against. I crawled under the car yesterday to inspect the cardan shafts and bearings and they look good. Am also wondering if a wheel bearing will cause this noise. I have also read that the differential can produce sounds but not sure what it is supposed to sound like. Looking for some feedback and suggestions. Thanks.

Steve

[wvicary]

A failing wheel brng or differential problem can often sound like tire noise. Rotate the tires front to rear or swap them with another set completely to help eliminate the cause. Does the noise change with loading (turning the steering wheel side to side) while driving at the speed it occurs at?

[hahnmgh63]

I would agree with wvicary. Rotate the tires front to rear and see if the sound changes. Besides the wheel bearing on that side also check the CV Joints. Once a wheel bearing starts going bad it usually doesn't last long but CV joints can slowly go bad over a fair amount of time. Try going down the road and do slight S turns to see if the noise changes pitch appriciably, if it does my bet will be on a wheel bearing or CV joint. They both normally last longer than this in Cayennes but it could be a bad joint/bearing or a torn boot causing premature failure. Hopefully just the tires.

Edited August 1, 2011 by hahnmgh63

[stevie s]

Thank you both. I will try rotating the tires. As to the change in noise based on the load levels, I do not hear a change. I was driving slow this afternoon trying to gat a good idea of where this is coming from and I am starting to feel that it could be the differential. I hear the sound start up when starting to move and I feel a slight vibration in the pedals. Could low fluid levels in the front differential cause this? To describe the sound another way it is a whirring sound that starts low and increases with speed.

Steve

[meszaros1]

any feedback on the problem? I'm chasing a similar noise...

Thanks

[clarksongli]

Thank you both. I will try rotating the tires. As to the change in noise based on the load levels, I do not hear a change. I was driving slow this afternoon trying to gat a good idea of where this is coming from and I am starting to feel that it could be the differential. I hear the sound start up when starting to move and I feel a slight vibration in the pedals. Could low fluid levels in the front differential cause this? To describe the sound another way it is a whirring sound that starts low and increases with speed. Steve

Low fluid can cas Diff noise, although if you are at that point, damage as already been done to the front diff.

niether problem would be felt through the pedals......

here is a way to tell if you have a tire or driveline problem.....drive at a normal speed where you can hear the noise and slightly lift off the gas so you are basically "neutral" and not accelerating or decelerating......

If the noise changes or goes away you got a diff problem......if it remains, it sounds like a tire or maybe a wheel bearing.

From what i can inspect on mine ( i have a diff problem) the pinion bearing and preload relaxes over time....this causes unacceptable lash on the gear contact area.....when you load and unload the power, the helical cuts preload the pinion gear/shaft into the bearing/housing.

the problem is common....the fix is expensive....and complete failure is low....basically drive on it....i've put 50k on mine and the noise is louder, but no collateral damage to note.