How to Silence Rear Axle Noise?

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Mine was so loud that I thought that people could hear it from a sidewalk. I eventually just had the gears changed again and bearings were replaced. I figure this will be the last time since I don't drive it often maybe two thousand miles a year. Still waiting for it to return from the supercharger installation. Things are really backed up at the mustang shop I go to.
 

Juice

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That sounds like classic symptoms of a wheel bearing going bad. Gets worse when you turn one way and not the other, in this instance, your right rear wheel bearing. You turn left, it's loading up that bearing and making more noise.

FWIW, I have 3.73s in my car and they are known to "sing" a bit while going down the road. What gears are in your car?
Wheel bearings in rear do not change noise turning. The side loading is handled by the carrier bearings. So if you have noise one way and not the other, it is a carrier bearing that is going bad. Except if you installed Cclip eliminators.
 

gbstang

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Wheel bearings in rear do not change noise turning. The side loading is handled by the carrier bearings. So if you have noise one way and not the other, it is a carrier bearing that is going bad. Except if you installed Cclip eliminators.

That is not necessarily true.. You DO load your axle bearings in a turn.. The C-clips only keep the axle in the carrier from wandering (for better words) the bearing retainer keeps the axle in the car.. The load felt during turns will be the axle bearings themselves and not the carrier bearings.
 

Juice

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Wheel bearings in c clip axles do NOT carry any side loading.
All side loading is handled by the carrier bearings through the c clips.

All the rears I have worked on, not many had a bad axle bearing. If you have a bad axle bearing, there is a real good chance the axle is also toast, as the axle is the inner race.
 

Rick Simons

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Generally speaking:
A pinion bearing issue will change with load and sometimes speed.
On these cars a wheel bearing will make more noise as speed increases, but won't necessarily change when cornering.
A carrier bearing will get louder as speed increases, AND when cornering. Since the axle bearings are the floating type, lateral (cornering) loads are transferred to the carrier bearings via the thrust block between the spider gears.
Another thing to check: does the axle housing get too hot to touch in operation?
 

Chistopher

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Another thing to check: does the axle housing get too hot to touch in operation?

I don't know, I don't usually touch the axle housing during operation. :)

I'm going on a bit of a longer drive tonight (1 hour) I'll give it a check. But the more that I look at it, the more I think it's just that the previous owner took out the factory noise deadening.
 

Chistopher

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Sound deadener did next to nothing. I did the entirety of the rear seats and trunk. My dB meter read exactly the same at 10, 25, and 45
 

Maczs007

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Ever since I upgraded my rear lower control arms I have had a constant scraping noise that sounds like a small pebble stuck between the brake dust shield and the rotor but it isn't that. I think it is just normal rear end noise amplified?
 

Maczs007

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Sound deadener did next to nothing. I did the entirety of the rear seats and trunk. My dB meter read exactly the same at 10, 25, and 45[/QUOTE

This guy uses two different materials and measures before and after:
 

Edmon

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For the investment of a couple hours and $40 of supplies (gear lube and Permatex), you can pull the rear cover and inspect the gears. Take note of excessive metal flakes in the oil or excessive wear on the gears. That's probably the easiest item to eliminate as a possibility. And I doubt the rear axle lube has ever been changed, so it needs to be changed anyway.
Could you help me here too please.
Having the same humming/griding noice.
But only when the car in decelerating!! At 30 or 60mph. Doesn't matter the speed.
Is this a pinion gear going in and out ?
No noice change when cornering.
Thanks in advance
 

Mach2burnout

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Could you help me here too please.
Having the same humming/griding noice.
But only when the car in decelerating!! At 30 or 60mph. Doesn't matter the speed.
Is this a pinion gear going in and out ?
No noice change when cornering.
Thanks in advance

Do you still have the back seat?
Do you have aftermarket UCA or LCAs?
Have your gears ever been changed or the gear lube changed?


Sent from my iPhone using Tapatalk
 

gbstang

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Could you help me here too please.
Having the same humming/griding noice.
But only when the car in decelerating!! At 30 or 60mph. Doesn't matter the speed.
Is this a pinion gear going in and out ?
No noice change when cornering.
Thanks in advance

Yup, sounds like gear noise for sure, especially if its only in decel.. If the backlash at the pinion/ring gear is incorrect it will definitely make noise either accelerating or decelerating.
 

Edmon

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Do you still have the back seat?
Do you have aftermarket UCA or LCAs?
Have your gears ever been changed or the gear lube changed?


Sent from my iPhone using Tapatalk
Hi, everything in car is stock. Back seats are in place. The differential oil was changed 5000km ago.
 

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