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Axle Bearing Failure?

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Was on my way to 2 days at VIR and noted an unusual whining noise that appeared to be coming from the rear of the car. I was about 100 miles from home and called the Ford 800 number to find the location of the nearest Ford dealer. Turns out there was one 10 minutes away. I drove to the dealer and the had one of their techs test drive the car. His analysis: axle bearing. He recommended I just return home and have my local dealer fix it since it could take a couple of days to complete the repair. I agreed and made it home OK. Tomorrow I'll drop the car off the at dealer and will report back after I find out exactly what the problem was. I am more than slightly pissed off. The hotel has a 24 hour cancellation policy and said they would need to charge me one night unless they get someone to book my room at the last minute. I may lose my instructor no-show deposit on the event (although I did call and let them know the situation) and worst of all...I WON'T BE DRIVING VIR THIS WEEKEND! :-((
 
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Oh man. What a bummer. What type of noise were you hearing? There are a few of us who are hearing a constant metallic rubbing noise from about 5 -40 mpg. Some say it is just the way the torsen diff sounds.... I took mine in to the dealer to have them document it and look at it. They say it is normal??? I removed the diff cover and looked at everything when I first started hearing it. Nothing looked out of place or smelled funny or anything. I am just going to keep my eye on it. Please keep us informed.
 
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It's a hard noise to describe. I may mount my GoPro at the back of the car and drive around a bit just to record the sound. You can begin to hear it around 10 MPH on up to 80 MPH+. Pitch changes with speed, and you can hear it best coasting in neutral so there is no exhaust noise. The service tech who drove it said it is not the diff or pinion gear and he's pretty sure it's a bearing. Will keep you guys posted...

Funny thing is the same dealer had new CO Boss on the showroom floor. As I was getting ready to leave, 2 twenty-something employees (I think they were both sales guys) came running out to check out my car. They said they've been asking the manager if they cound start up the one they had and he won't let them. I had the side pipes fully uncorked in prep for VIR so I was happy to accomodate them. Made their day.
 
Bummer. There was a guy on another forum that had a early build car and had the same problem within weeks of owning the car. It took his dealer a few days to order the parts and install them. Good luck.
 
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Interesting thing I noted: You can barely hear the noise with the back seats up but it's very noticable with the seats down. That means it may have been doing it for a long time and I only noticed it when I put the seats down to load some stuff in the car. At any rate, the car is at the dealer now. We'll see what they find out...
 
Oh man I just saw this thread Chuck. I hope it's just the normal rear end noise we get in these Mustangs. It's definitely loud if you put the seats down. That's why I'm going to do a rear seat delete when the roll bar goes in. I'm sorry you missed out on your track weekend. Let us know what the dealer says.
 
The noise was much louder and noticable when I removed the seat bottom a few weeks ago, that was with the seatbacks still up. I have the seat delete in and it does a good job of blocking the noise, you can still hear it but it is not that bad. I never listen to the radio but if I did it would block it out even at low volume. I do not worry about it.

Daytime pics

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CIMG2389.png
 
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cloud9 said:
Oh man I just saw this thread Chuck. I hope it's just the normal rear end noise we get in these Mustangs. It's definitely loud if you put the seats down. That's why I'm going to do a rear seat delete when the roll bar goes in. I'm sorry you missed out on your track weekend. Let us know what the dealer says.

Normal rear end noise? It sounds like a component in mechanical distress. How can ANYTHING so obnoxious be normal? Is it only the TORSEN that makes that horrible noise? If I threw away two days at VIR, one night hotel charge and an instructor no show deposit forfeit for "normal" noise I'm livid!!!! If that's the case the noise should be mentioned in the Boss 302 supplement (maybe it is and I missed it).

I hope it's NOT just the normal rear end noise. I'll at least feel the weekend was not thrown away for nothing!!!
 
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PTRocks said:
I had a similar noise with my car. It was the ring gear that was pitted. Get the dealer to do a visual inspection of the gears.

1314635639-random-pics-your-boss-302-p1020226small.jpg

After they did the repair do you still get a lot of noise for the rear end? Mine is loud enough with the seats down that I can still hear it with fully open side pipes while cruising on the highway with the radio on. I had to crank up the volume to mask the noise. Just want to know what's considered "normal" before I insist the dealer open up the diff.
 

BLAZN BOSS

I use to do rear end work for a lot of people in the area I live in, both for the shop I owned and at home, mostly 9" ford, some GM and dodge. I see some small places that I guess your calling pitting and I can tell you that some of the guys that bring me gears are used from a buddy and the want to go to the track and use it askeing me to set it up for them........actually pitted from rust ........but no noise. What I do see in that picture is an AWEFUL gear wear pattern........terrible run off on the heel .......you unfortunatly didn't capture the other side of the gear tooth for me to see. This gear wear pattern Im seeing would definetly make noise. I cant tell what's going on without being there but that ring and pinion set would go in the trash. And after setting a new set up and checking wear pattern if it showed up like that again I would even run it and would look for a new housing. I have set up just every day drivers to sub 8 second rears and would never let that out my garage that looked like that.
 
My car makes the same noise. When I took it to the dealer they had their senior mechanic ride with me. He said it definitely wasn't wheel bearing. He thought it was normal road/ gear noise. If this noise is caused by improperly assembled rears, I wonder how many are done wrong? There is a lot of us that have noticed it.
 
ChuckP said:
cloud9 said:
Oh man I just saw this thread Chuck. I hope it's just the normal rear end noise we get in these Mustangs. It's definitely loud if you put the seats down. That's why I'm going to do a rear seat delete when the roll bar goes in. I'm sorry you missed out on your track weekend. Let us know what the dealer says.

Normal rear end noise? It sounds like a component in mechanical distress. How can ANYTHING so obnoxious be normal? Is it only the TORSEN that makes that horrible noise? If I threw away two days at VIR, one night hotel charge and an instructor no show deposit forfeit for "normal" noise I'm livid!!!! If that's the case the noise should be mentioned in the Boss 302 supplement (maybe it is and I missed it).

I hope it's NOT just the normal rear end noise. I'll at least feel the weekend was not thrown away for nothing!!!
The "normal" noise is a low level hum or whirring noise which is mostly masked with the seats in upright position. If it's something other than that it's quite possibly a more serious mechanical issue. Not having heard what you're hearing, there's no way to know if it's other than "normal".
 
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The "normal" noise is a low level hum or whirring noise which is mostly masked with the seats in upright position. If it's something other than that it's quite possibly a more serious mechanical issue. Not having heard what you're hearing, there's no way to know if it's other than "normal".
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As I said I could still hear it with side pipes wide open and radio on. We'll see what dealer says. Thanks.
 
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Here's the latest update:

Dropped the car off at Waldorf Ford on Sat, 11/13. Not having an appoinment, the service advisor said they would get to it late Monday or early Tuesday. On Wednesday afternoon Dave (the SA) gives me a call and says they have found a "suspect" bearing in the diff and ordered the part. Dave calls me back on Friday afternoon and says they replaced the bearing, put it back together and the noise is still there. They then called Ford who tells them it's probably "normal". Dave has the service manager drive the car. He determines it is NOT normal. It just so happens that Waldorf has an unsold Boss in stock so Dave and his manager take it for a spin with the back seats down. Some normal whine from the diff but MUCH less than my car and certainly not objectionable. Service manger gets on the phone with Ford and they approve a whole new rear axle assembly...the whole enchilada. Since that will take a few days to come in I picked up the car today and will bring it back when the axle comes in.

Now a footnote: last month I replaced the rear axle lube, per the Boss 302 manual supplement, after the first track day. I used Royal Purple Max Gear 75W140 full synthetic. I confirmed it meets or exceeds all Ford specs. Dealer is aware (it was still purple when they drained it) and said there is no problem with the choice of lube I used...it's fine...no warranty worries. However, in the future I think I will ONLY use Motorcraft fluids (with the exception of brake fluid) in my Boss.

I put my GoPro on the back window and drove around a bit to record the noise. It is FAR more noticable live than in the recording but I think you will hear it. I recommend you skip to 8:00 and start listening there. You should be able to hear it during easy acceleration. Than between 8:45 and around 9:10 you should be able to hear what it sounds like at higher speeds. If this is the "normal" sound of a torsen they may be putting a whole new rear axle on my car for naught!

http://www.youtube.com/watch?v=Rce_Xx2X5VE
 
Thanks for the update Chuck. It's kind of hard to tell from video, but is there a metallic almost screeching sound? If so, that would not be normal but it's really tough to tell from the video. The noise I hear from mine is more of a whirring sound and like you can hear the rear pads "rubbing" on the rotors.
 

BLAZN BOSS

Cars going straight dont have noise because of any type of differential unit regular traction loc or torsen, (some old detroit lockers made a clanking when the springs wore). Straight down the road the only thing that can make noise is the pinion bearings, differential carrier bearings, axle bearings or ring and pinion set. The dealer replaced your bearings and the noise was still there because from the wear pattern I saw it was the ring and pinion anyway. Now there can be ring and pinion noise but at a low level. Its two gears working together. But not so audible that its anoying. Your getting the best deal by them replacing the whole unit..........mechanic probably dont want to keep trying till its gone. Now with these Bosses we all have carbon fiber clutch plates and when turning into say a parking spot you can hear a sound...sorta "whoop whoop" ........like when cleaning a window and the rags squeak. THAT is a normal noise. If they were the regular clutch plates the friction modifier would get rid of it.........but thats only for traction lock rears. If it were my car I would ask if I could heat gun the stickers off the old housing..........keeps the history of the car. Also have them log it in your owners manual and they can stamp it that you have a replacement factory rear end. I wonder if these rears have the cars serial number stamped in it????
 
That does not sound much different then mine but maybe a lower pitched sound. Best I can describe mine, it sounds like a cricket on a hot summer day in a field off in the distance.
 
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It's a metallic sound...almost a whine above 50 MPH. Loud enough I can hear it with the side pipes uncorked and the radio on if the back seats are down. Dealer agrees it's not normal so I guess I'll be getting a whole new axle. I'll keep you posted...
 
ChuckP said:
It's a metallic sound...almost a whine above 50 MPH. Loud enough I can hear it with the side pipes uncorked and the radio on if the back seats are down. Dealer agrees it's not normal so I guess I'll be getting a whole new axle. I'll keep you posted...

Chuck, none of us doubt you - just saying these things are fairly noisy. Keep us posted if they do find any problems.
 

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