Help me ID sound!

[Svashtar]

Guys, sorry this is kind of a BS post, but as you have helped me with so many other issues with my car I thought you might have an idea on this.

I always have the radio on, and today was driving on a smooth street, very slowly at 20 MPH, just coasting with no engine sound, with the windows up and the radio off. I heard a distinct continuous soft "thrumming" coming from what sounded like the right rear tire area, but hell it could have come from the rear end.

Maybe it has always been there and I just cluelessly never paid attention, or maybe I've just become more perceptive, but now that I have keyed in on it it's all I seem to hear. Maybe it's totally normal?

Anyway, the faster the car coasts the faster the cycle of thrumming (I hate to use that word but it's the only one that fits.)

The car has 26,500 miles on it. I had the 4:10's installed 22K miles ago by a guy who knows his business, and have had zero issues. He checked for the axle TSB issue at the time he did the gears and reported no wear at all, and insisted the soft axle problem would be showing at 4K.

Could it be a wheel bearing? Most folks would hardly even notice this, but it's bugging me.

Q: how often should the differential oil be changed? The wheel bearings repacked? I know it used to be 15K miles on older cars but not sure if that has changed.

Any ideas?

Thanks as always!

Norm

[Blackened300a]

Check for something in the tire threads, a rock would give you a rapping sound and something softer my give you the noise you are hearing, also check the parking brake. Maybe a spring came off or its hung up a little in the rotor.

[Svashtar]

Thanks very much, but no rock. Even one the size of my fist wouldn't make a sound like this. Definitely a mechanical sound, with a constant cyclic rate to it. I don't know what gears sound like when they are going bad though. I'm thinking about _carefully_ jacking up the drive wheel and running it in gear and see what I can find out. To me it sounds like something inside the wheel, but that's just my untrained perception.

Thanks,

Norm

[69marquis conv]

Any chance you could have cupped areas in your tire?

[CRUZTAKER]

I'd start with the inspection of the tire. Perhaps swap sides with it.
It would be a perfect world if you could actually rotate it forward. You could rotate both sides to the front for a slow walk down your street just hear if the sound remains.

If it isn't tires, it could very well be gears. My 4:10's have a distinct sound from about 28 to 38 mph cruising. I posted a thread regarding this when I had mine done 3 years back. They did it for a long time without any issues.
I'd like to further comment on the sound remaining all this time on that set of gears, but they have since bit the dust at the mercy of some very sticky Mickey Thompsons some time ago. :P

[Svashtar]

Any chance you could have cupped areas in your tire?
Hmm, I'll check it out thanks, but offhand it's just not that kind of sound. Wish I could describe it to you. Hey, you know those old WWII submarine movies, where they show the boat underwater and the prop is making that constant thrumming/pulsing sound? That's it exactly. (If I was in a sub I'd be happy. :))

The tires are getting close to replacement. Wear down the middle of the rears and on the front insides, even though the dealer insists the car is in alignment spec. Not too bad but there. But they are in good shape otherwise.

I also think it's the tire because the noise increases when I make a left turn, which means the right outside tire is turning faster. Of course the pinion gears kick in during a turn as well, right? but it just gets louder, doesn't start for the first time.

The parking brake is a good suggestion. I'm just paranoid about the gears as it took me forever to find someone qualified and able to do the work. I know it's soon in the life of the car, but I think it might also be a damaged or bad bearing.

Thanks again.

Norm

[Marauderjack]

Norm,

If it is a "Wump...Wump...Wump" sound that increases with speed it is probably a wheel bearing or axle issue......Been there...Done that!!:argue:

If you are still in warranty your dealer should fix it free!!:beer:

If not the complete "Kit" from Ford is about $300.00!!

Good Luck and let us know what you find!!

Marauderjack:burnout:

[hbarrett]

I am having the same problem now, and sounds like it is coming from RR wheel - '04 MM, 25k miles. Had dealer install 410s 20k miles ago, and just started making a noise at rear wheel. Noise is most distinguishable at 20 to 30 mph, but may be because there is less road noise at that speed. Dealer replaced outer wheel bearings under warranty and noise is still there, now they tell me that it needs inner bearing replaced. I will find out Wed if this fixes the noise. I suspected the gears, but they are saying 'no way.'

Guys, sorry this is kind of a BS post, but as you have helped me with so many other issues with my car I thought you might have an idea on this.

I always have the radio on, and today was driving on a smooth street, very slowly at 20 MPH, just coasting with no engine sound, with the windows up and the radio off. I heard a distinct continuous soft "thrumming" coming from what sounded like the right rear tire area, but hell it could have come from the rear end.

Maybe it has always been there and I just cluelessly never paid attention, or maybe I've just become more perceptive, but now that I have keyed in on it it's all I seem to hear. Maybe it's totally normal?

Anyway, the faster the car coasts the faster the cycle of thrumming (I hate to use that word but it's the only one that fits.)

The car has 26,500 miles on it. I had the 4:10's installed 22K miles ago by a guy who knows his business, and have had zero issues. He checked for the axle TSB issue at the time he did the gears and reported no wear at all, and insisted the soft axle problem would be showing at 4K.

Could it be a wheel bearing? Most folks would hardly even notice this, but it's bugging me.

Q: how often should the differential oil be changed? The wheel bearings repacked? I know it used to be 15K miles on older cars but not sure if that has changed.

Any ideas?

Thanks as always!

Norm

[hbarrett]

Dealer fixed the problem today. Pitting in the bearing race caused the noise.
I am having the same problem now, and sounds like it is coming from RR wheel - '04 MM, 25k miles. Had dealer install 410s 20k miles ago, and just started making a noise at rear wheel. Noise is most distinguishable at 20 to 30 mph, but may be because there is less road noise at that speed. Dealer replaced outer wheel bearings under warranty and noise is still there, now they tell me that it needs inner bearing replaced. I will find out Wed if this fixes the noise. I suspected the gears, but they are saying 'no way.'

[Svashtar]

Norm,

If it is a "Wump...Wump...Wump" sound that increases with speed it is probably a wheel bearing or axle issue......Been there...Done that!!:argue:

If you are still in warranty your dealer should fix it free!!:beer:

If not the complete "Kit" from Ford is about $300.00!!

Good Luck and let us know what you find!!

Marauderjack:burnout:

That is exactly what it sounds like thank you!


I am having the same problem now, and sounds like it is coming from RR wheel - '04 MM, 25k miles. Had dealer install 410s 20k miles ago, and just started making a noise at rear wheel. Noise is most distinguishable at 20 to 30 mph, but may be because there is less road noise at that speed. Dealer replaced outer wheel bearings under warranty and noise is still there, now they tell me that it needs inner bearing replaced. I will find out Wed if this fixes the noise. I suspected the gears, but they are saying 'no way.'

Yes, this is exactly my experience. 25K miles and 21K miles since the gears were installed. Don't hear it at all for the first 2-3 miles, and then it kicks in. Can hear it best at about 25 MPH, but road noise makes it harder to hear at higher speeds. Except the difference is my mechanic installed my 4:10's as the dealer wouldn't do it, and even though they are Ford gears they are considered an out of warranty mod.

Thanks very much to all! I am sure it is the bearing as well. The hell of it is, I know this dealer and if he knows about the 4:10's he will insist that they are causing the problem.

If it WAS the axle, then I would lose the gears, correct? Couldn't the dealer just change out the axles without messing with the gears? I have a stud and girdle kit on the thing, so he knows they're there.

Man, I hate talking this thing to the idiot. He screws up something else every time. I'll keep my fingers crossed and hope it is only the bearing.

Thanks again.

Norm

[hbarrett]

Good Luck! Please be sure to let us know how you make out with this problem.
That is exactly what it sounds like thank you!



Yes, this is exactly my experience. 25K miles and 21K miles since the gears were installed. Don't hear it at all for the first 2-3 miles, and then it kicks in. Can hear it best at about 25 MPH, but road noise makes it harder to hear at higher speeds. Except the difference is my mechanic installed my 4:10's as the dealer wouldn't do it, and even though they are Ford gears they are considered an out of warranty mod.

Thanks very much to all! I am sure it is the bearing as well. The hell of it is, I know this dealer and if he knows about the 4:10's he will insist that they are causing the problem.

If it WAS the axle, then I would lose the gears, correct? Couldn't the dealer just change out the axles without messing with the gears? I have a stud and girdle kit on the thing, so he knows they're there.

Man, I hate talking this thing to the idiot. He screws up something else every time. I'll keep my fingers crossed and hope it is only the bearing.

Thanks again.

Norm