Groan in rear end when turning

[jimprw]

Anyone have a groan coming from the rear end when turning? It is especially noticeable when turning at low speeds, and happens turning left and right.

I thought I saw something on this in one of the other topics but can't find it. At first I thought it might be from the electric steering motor (?), but after much listening it is definitely coming from the rear of the car. Only thing I can come up with is that it is tire noise from the big meats in back pivoting on the pavements as the vehicle turns or it is something more serious in the differential. I have the standard limited slip differential, not the Torsen.

 

[atrain1975]

I started threads on this site and TMS regarding grunts, groans, and creaking on the front end over speed bumps, up driveways, and on acceleration from standing. This might be what you recall reading about, but apparently a different problem than what you are experiencing.

Try posting a thread on TMS to see if you can unearth other Boss owners with the same problem.

Good luck.

 

[jimprw]

This groaning from the rear end in my Boss has continued - sometimes pretty loud, sometimes not so much and sometimes not at all when I first start driving it - but always when I've been driving it to some extent. So, at 2650 miles I finally took it in to the dealer. I had the service manager jump in the car as soon as I arrived to be sure they were hearing what I was hearing , and he did saying "that doesn't sound good...sounds like something is rubbing".

What I got back was that this was normal (?) based on Special Service Message #21287 on Oasis which I'm assuming is an/the internal network service site for Ford service technicians. In case anyone other than me has the same problem at some point I'm going to copy the meat of the service bulletin word for word on the following post

 

[jimprw]

Oasis Special Service Message Number: 21287
Message Title: 2007 - 2011 Mustang Carbon Fiber Limited Slip Differential Normal Noises
Applicable Vehicles: 2007 - 2011 Car: 00071 Mustang

Oasis Message:
2007-2011 Mustang GT500, Mustang GT Equipped with Brembo Brake Package, 2010 Mustang GT Equipped with TrackPack, 2008-2009 Bullitt - Limited slip differential normal charactistics. These vehicles are equipped with heavy duty/racing type carbon fiber clutches in the limited slip differentials. This type of limited slip differential may exhibit a chatter or moan/groan noise when making sharp low speed turns. These noises are a normal characteristic of the heavy duty/racing type limited slip differential. Note: Driving the vehicle in a tight figure eight pattern 5 times may lessen the complaint for a short period of time.

So there you have it. Strange to me Ford didn't/couldn't engineer that out. Even stranger that no one else here on this forum has seemed to have the same issue. But, for now it looks like I have to live with it.

 

[VoodooBoss]

I recently contacted Torsen and asked them if the friction modifier is required in their diff. I had heard that it wasn't. They responded that it's not necessary and that Ford had probably specified it to help quiet the diff while turning at low speeds. I have not noticed any noise while turning at low speeds in my Boss but I'll try and listen for it. Did you have your diff fluid changed recently?

 

[jimprw]

Nope...differential fluid as delivered from the factory. Also just to clarify, I have the standard limited slip differential rather than the TorSen. I'm not sure what components they might have that are the same, but suspect they are different animals. Note, too, that apparently these heavy duty/racing differentials have been installed in certain models of Mustangs since 2007 it seems.

 

[2012YellowBoss]

So there you have it. Strange to me Ford didn't/couldn't engineer that out. Even stranger that no one else here on this forum has seemed to have the same issue. But, for now it looks like I have to live with it.

I would not worry about it, sounds normal. If they engineered the noise out then you have an open rear.

 

[STIG302]

So there you have it. Strange to me Ford didn't/couldn't engineer that out. Even stranger that no one else here on this forum has seemed to have the same issue. But, for now it looks like I have to live with it.

I would not worry about it, sounds normal. If they engineered the noise out then you have an open rear.

I don't hear much over those side pipes! Not even the Mrs. ;D

 

[MrGT5oh]

Not even the Mrs. ;D
[/quote]

LMAO

 

[Silnickius]

I have noticed this as well on my Boss. Still drives fine, but it is annoying.

 

[BOSS 1276]

GT500's have the same issue. Do you have the standard trac-lok or the torsen diff?

 

[PJWANNABE]

Doing slow sharp turns my '08 Bullitt's rear did that, and so did the clutch. The friction modifier helped silence the rear clutch packs; the clutch coudn't be helped.

 

[atrain1975]

My boss is now making the grunt / groan from the rear end on low speed right turns. I have the torsen. Has anybody else with the torsen had this issue? The noise is almost exactly the same as the front end noise i had before replacing the LCAs.

 

[2012YellowBoss]

My boss is now making the grunt / groan from the rear end on low speed right turns. I have the torsen. Has anybody else with the torsen had this issue? The noise is almost exactly the same as the front end noise i had before replacing the LCAs.

Mine is fine but I have seen others say something on the other board. Unless it is real loud I would not worry if it were mine. Plus you have a long way to go on warranty if it get louder.