Tire noise or something seriously wrong

[jpu535]

I have an '02 explorer XLT 4 door with Michelin Cross Terrain tires 235-70-16. I have had a low pitch groaning noise that sounds like an old fire truck siren winding up or down. The noise starts at about 35 mph and gets louder and increases in pitch as I accelerate. The noise appears to be coming from the rear wheels or rear end. I noticed that as I make a right sweeping turn at speed, like a highway exit or entrance ramp, the noise gets louder. However, if I make a left turn it disappears completly. The noise will return as soon as the truck straightens out. The Ford dealer I bought the truck from tells me that it's tire noise and not to worry about it. I ran into another guy that has the same model truck and tires and he says his rides quiet. I have already checked tire pressure and they are to spec. I have also rotated tires and and readjusted the tire pressure accordingly and that didn't solve the problem.

Any one have any experience with this type situation? I would appreciate your suggestions.

By the way, I already checked and there is no siren under the rear of the truck.

Thanks in advance.

Joe

 

[bhults]

You might want to have your wheel bearing assy's checked out. I have a '95 EB, and I recently had to have mine replaced. My truck was making the same type of low hum noise you're talking about...at first I thought it was just tire noise..but it was louder when I was turning to the right, quiet when I turned to the left, and somewhere in between while driving straight. I don't know what kind of lifespan wheel bearings have---my truck being a '95, it probably needed them, but since yours is only an 02, I'd see if the dealer could hook it up under warranty. Also, don't let this problem go too long---I was told that bad bearing assy's can eventually harm your auto hubs (if you have 4wd). Good Luck!

 

[taxx]

4x4s don't have "hubs" in the old school way.

The bearing assembly is the hub. It is a sealed unit on the 4x4s and is not cheap to replace, cheapes I found them was for $125 or so. If it goes bad you'll know it and it will vibrate and grind like crazy. As long as that CV halfshaft is in there it won't seperate, but if it gets really bad you could cause potential problems to the CV half shaft, but if it is that bad your gonna have more problems than that such as dring straight and safely.

humms and grinind are usually bearings.

hums can also be tires.

Just noticed you are taliking about the rear oh well

Your noise sounds like a bearing. being under warrantee I would get it checked out. The turn could be putting more stress on it makeing it more noticeable.

 

[bhults]

Interesting...I didn't know it was all one unit. Yes, expensive is the name of the game. I paid close to $750 for parts and labor (both sides were done)....but at least it's nice and quiet now.

 

[taxx]

Rear is not all one part. But it is an interesting job to replace them. Being an 02 it should be under warrantee???

 

[jpu535]

Thanks to everybody who replied. Armed with the info I went to a different dealer and they confirmed a bad left rear bearing and hub. I have the premium care extended warranty and they said it was covered, until they got 4 hours into the job then all of a sudden it was a $650 non-warranty repair they wanted me to pay for. I argued that the brochure Ford uses to sell the warranty lists bearings and hubs as covered but they disagreed. I ended up calling Ford Customer Response in Michigan and got an interesting explination on what is covered and what isn't on these extended warranties. I'll post that to a seperate reply under "Ford Extended Warranties" in case anybody is interested.

Thanks again,
Joe