DJ Piner

Hi Guys, I have a 2008 GT vert with only 35K miles with auto transmission. Had the car for just over two years with no issues. Today I noticed when I make a hard left or right turn such as turning in my driveway my rear axle is making a loud whining noise. Anyone have any ideas what this might be. It does have a limited slip rear end. Clutches gone bad maybe???? I don't have a clue. Any help or ideas are greatly appreciated.

drewsky

Are you 100% sure it's your rear end? These things are pretty noisy as is in these cars. But whining all if a sudden is strange... Maybe it's coming from your trans or something stupid like low power steering fluid? Pretty much all the components in these mustangs are very reliable but noisy. Made to perform just not be luxurious like a bmw or Mercedes you know .. Mine has been noisy in every way for 5 years but love it still.

DJ Piner

No I'm 100% sure it's coming from the rear axle. Just afraid of the cost to repair if clutches need to be replaced or if that is even possible.

jpplaw

Could be the clutches. They do sell a replacement kit with Carbon clutch discs. Maybe first try draining the rear end first and do a refill with a good (Royal Purp, Mobile 1, Amsoil) 75/140 oil and a bottle of Ford friction modifier and see if it quiets it down.

DJ Piner

Took it by my local dealer and they pulled the rear cover. Clutches are bad and the wear pattern is way of on the ring gear. It has a 3.31 gear so if I have to replace it I'm thinking of going back with a 3.55. Don't understand how wear pattern is off so much from the factory. It doesn't have 36K miles on it yet. Has anyone used the ring and pinion complete kit from AM and if so does it come with everything needed (except clutches)? The dealer cost is just over $1500.00 out the door parts and labor:-(

jpplaw

My car came stock with 3.31 gears. Started whining at 16k miles. Got them replaced under warranty. Those very quickly chewed themselves up and another warranty replacement happened. Those started whining in another 5k miles or so. Supposedly the dealer's top gear expert was setting them up too - and this was Tasca Ford, so you would think they would know what they were doing. I got fed up and at that point, I gave up and bought the 2012 GT500/Boss 302 complete Axle assembly (stock 3.73 gears) from American Muscle. It was around $1200 with the forum discount. Did the replacement right in my driveway. A little awkward but very easy to do. So $1200 (plus a couple hundred labor, if you don't or can't do it yourself) could have you a whole new stronger rear end with upgraded gears and clutches. I would seriously consider going that route, I do not regret it at all.

I have never had another problem with gears since - and I'm pushing ALOT of power. I did replace the axles later with Mosers but that was just for racing "insurance" purposes.

3.55 isn't very much of a change from 3.31, but 3.73's will really wake the car up and you'll love the response.

ticopowell

I would try and get the dealer to fix it under warranty, a 2012 with less than 36k should be pretty close to still being under warranty. I agree a whole rear end might be cheaper, and the boss torsion diff doesn't have clutches to wear out next time.

PNYXPRESS

Mine was doing the same thing. Took it in under warranty and they found that it was due to being low on fluid. They did the turkey baster TSB, topped off the fluid, and added friction modifier. Hasn't made a sound since. I also have the 3.31 gears

jpplaw

Having the dealer (or anyone, really) set up gears is like a crap shoot. Sometimes you win, sometimes you lose.
Also, from what I have heard, the pumpkin castings are made in mexico and some are doomed from the beginning due to casting flaws.

moosestang

You could buy a whole rear axle from american muscle for less. Don't pay the dealer $1500. I'd rather have a dedicated race shop or transmission shop set up my rear gears.