Rotational noise? Drive shaft?

[Countryboi]

Hello, brand new here, on my fourth Mustang, a 2008 GT with 53K original miles I bought today. Two weeks ago I had just gotten a 2007 GT/CS with 91K but in excellent condition. Two semis decided they wanted to be in my lane so...it got totaled.
In driving the new(er) car home tonight, I noticed the exact same noise in the '08 as in the '07; a "rotational noise." Now I'm deaf in one ear, the other not much better, so I could be confused, but I've heard all the tales about the two piece driveshaft so I'm wondering if that's what's making all the racket. I don't know how to describe it other than "rotational" since it sounds like I'm driving on tires worn down to the wear indicators. Kind of annoying even being deaf.
Would the one piece aluminum drive shaft Ford markets be a cure? Thanks in advance.

 

[msvela448]

Where is the noise coming from? Is it under the arm rest where the 2-piece driveshaft carrier bearing is located? Or is it coming from the back of the car where the axle is located? My first thought is... Does the car have different rear end gears? Sometimes aftermarket gears "whine" a little, especially if a home-mechanic put them in and didn't set them up properly (just reused the stock shims). Is it worse when accelerating or decelerating, or is it a consistent sound all the time?

Sent from my SM-N986U using Tapatalk

 

[GriffX]

This is a document to locate noises from Ford. I have a noise from the driveshaft which is only speed dependent no matter if accelerating or decelerating.

 

[Countryboi]

Being deaf in one ear, and very impaired in the other, it's sometimes hard for me to tell, but it does sound like it's coming from that armrest / rear axel area. Mostly when I get about 40 mph. On the '07 the rear output shaft seal was leaking so that may have contributed. The '08 I don't know, haven't crawled under it very far to see what's going on under there, but at 54k I didn't think that carrier bearing would be this noisy. In fact, I'm surprised at the amount of road noise in these cars. Could be me I guess, but it sure is noisy.
I appreciate the noise finder info! That will help, but I think in the end getting rid of that two piece shaft will go a long ways at fixing this issue. But boy are they proud of those things!

 

[GriffX]

I just did the noise insulation job and I could kick myself that I have not done it years before. The car is noisy and I found almost no noise insulation anywhere besides the floor pan. It is so much more enjoyable to drive now.
With the document you should be able to locate the noise to the diff or the driveshaft, I guess.

 

[Countryboi]

Is there info out there about the "noise insulation job"? Or is it in that pdf on locating noises?
Also I found a NEW noise! When I go to start the car, I get a loud bang coming from under the dashboard, like a vent slamming shut or something. WTH??

 

[JC SSP]

Lol notorious HVAC blended door actuators. There are four of them in total.

Search the forum, someone posted a step by step guide.

 

[Countryboi]

Wow, thanks!

 

[GriffX]

Is there info out there about the "noise insulation job"? Or is it in that pdf on locating noises?

Yes, I did not the "everything alubutyl" route, I use the Quite Ride documents to place alubutyl stripes and combined it with car sound insulation self-sticking sheets form a special German company on the inside of the covers. I have cut tons of 2x20 alubutyl stripes and combined them.

https://www.quietride.com/web/viewe...nstructions/AS/Ford/Mustang/MUST 1014-CAK.pdf

https://www.s197forum.com/threads/w...lation-make-the-most-difference.140239/page-4

 

[Countryboi]

Thanks so much!

 

[Dcraig10004]

Get rid of the two-piece driveshaft. It will absolutely cure this noise. It's like night and day. Go for the For Racing one-piece aluminum driveshaft. You will be amazed.

 

[Countryboi]

That's what my plan was! I'm definitely doing that, and maybe the noise reduction insulation too. I had to make an hour drive this morning and it drove me nuts!
Thanks!

 

[MrBhp]

Our cars are also very susceptible to tire noise. Another thing that insulation can help with. That s197 link posted above is good. Start at the beginning of the thread.

 

[Countryboi]

Don't I know it! Mine has some Pirellis on it now and they're very noisy. I know tire noise is not any easy fix, but that driveshaft....got to go!
Everyone has such good info here!

 

[Doobage1922]

Get rid of the two-piece driveshaft. It will absolutely cure this noise. It's like night and day. Go for the For Racing one-piece aluminum driveshaft. You will be amazed.

Does the mustang being lowered effect anything? As far as the 1 piece drive shaft? For instance, mine is on eibach lowering springs, do i need anything else, or can I install the 1 piece drive shaft without any other components?

 

[Laga]

Does the mustang being lowered effect anything? As far as the 1 piece drive shaft? For instance, mine is on eibach lowering springs, do i need anything else, or can I install the 1 piece drive shaft without any other components?

The rear of the driveshaft from The Driveshaft Shop comes with a CV joint at the back. This will accommodate any changes in DS angle due to lowering, nothing else involved.

 

[aharris042]

I’m going to kind of revive this thread. My 07 GT with 56,000 miles on it just started having some sort of rotational noise coming from the rear end out of nowhere. It’s high pitch and starts around 40 mph. it doesn’t get any worse or any better with acceleration or deacceleration. It only gets louder or quieter with the speed I’m going. It’s not your typical differential sound that sounds more like a clunking and roaring sound. It’s much higher pitch than that. I’ve got a new driveshaft on the way and I’m really hoping that fixes it.

 

[JC SSP]

Check your differential fluid level and condition?

 

[aharris042]

Check your differential fluid level and condition?

Has been recently replaced along with the diff additive.

 

[JC SSP]

High pitch to me means gears or bearings inside the differential... I don't think the drive shaft will make that noise, but you never know... Please keep us informed on what you find.