# Whine when slowing down from 50 to 40 mph



## PatrickNJ (Apr 21, 2006)

'05 A4

I noticed a slight whine when the car slows (letting off the gas completely or using the brake) down only in the range of 50 to 40 mph. I have 15,000 miles on the car and was wondering if anyone has a similar problem and what you decided to do.
This may be related to reared whine but some of the members of this post say that it happens when they accelerate in the 40 - 50 mph range. 
Should a flag be raised the next time I see the dealer?

Thanks,
Pat


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## GTO JUDGE (May 14, 2005)

PatrickNJ said:


> '05 A4
> 
> I noticed a slight whine when the car slows (letting off the gas completely or using the brake) down only in the range of 50 to 40 mph. I have 15,000 miles on the car and was wondering if anyone has a similar problem and what you decided to do.
> This may be related to reared whine but some of the members of this post say that it happens when they accelerate in the 40 - 50 mph range.
> ...


If the sound is coming from beneath to the rear of the car it very well could be the rear end whine. Although the symptoms are synonymous with acceleration what you describe is similar. I'd get it checked out.


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## PatrickNJ (Apr 21, 2006)

Thanks, the next time i get an oil change I will tell them about it.
It seems like everytime I take the car for an oil change I have an issue.
But what else is new.


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## Rukee (Feb 8, 2007)

Your car's whining when it slows down cause it wants to go faster. 




Sorry, couldn`t resist.


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## GTO JUDGE (May 14, 2005)

Rukee said:


> Your car's whining when it slows down cause it wants to go faster.
> 
> 
> 
> ...



:lol::lol::lol::lol::agree


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## PatrickNJ (Apr 21, 2006)

I wouldn't be surprised. Either that or maybe it just wants to retire.
Oh well I will keep you posted on my next visit to the dealership


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## cody6.0 (Nov 28, 2006)

My car had 4,000 miles and had the exact same symptoms.

Bearing pre-loads and backlash all effect pinion movement which is what makes gears whine during accel or deaccel. Most of the time being set up results in whine during accel and too loose will cause whine during deaccel.

Although keep in mind all gears make noise but some can be canceled out. GM had to deal with this issue in alot of it's trucks and SUV's.


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## PatrickNJ (Apr 21, 2006)

Cody,

So what did they end up doing to your ride?


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## cody6.0 (Nov 28, 2006)

Well I originally had them order a new replacement diff but when it arrived it was the same part number as my old one. So I said screw it and just lived with it until I traded it in.

I am starting to belive these diffs are just loud. Too many people have had noise then replaced it only to get some noise back later.


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## GTO JUDGE (May 14, 2005)

cody6.0 said:


> Well I originally had them order a new replacement diff but when it arrived it was the same part number as my old one. So I said screw it and just lived with it until I traded it in.
> 
> I am starting to belive these diffs are just loud. Too many people have had noise then replaced it only to get some noise back later.


The rear ends all have the same part number. The rear end is one complete unit compromised of many parts. No matter what part you buy for the car, the part number will always be the same. If the part number is different, then the part is different. 

You are incorrect in your assumption it is the nature for these rear ends to be loud. Mine is as quiet as a church mouse. Every car or truck I have ever owned in my life was never loud. The car manufacturer does not build a car to be noisy. If there are noises coming from the rear it is not normal. Dana built a bunch of bad rears, some guys who have had their rears replaced got bad rears again. Some took 2 or 3 rears installed before they got a rear that was quiet.

I have ridden in many performance cars and have not experienced loudness coming from the engine, transmission or rear end. The easiest thing one can do is dismiss it as normal and forget about it. 

My replaced rear got noisy a while after it was installed. That problem turned out to be a break down of gear oil viscosity. Had I dismissed it as a "normal" loud noise eventually heat would have gotten to the gearing and turned a simple fix into a major deal.

GM opted to replace rears, if the noise was normal, they would not have spent the money to fix a potential "non problem."


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## NJG8GT (Nov 14, 2007)

Maybe you ran over a mustang or a ricer and it is still stuck under your car?:lol:


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## cody6.0 (Nov 28, 2006)

GTO JUDGE said:


> The rear ends all have the same part number. The rear end is one complete unit compromised of many parts. No matter what part you buy for the car, the part number will always be the same. If the part number is different, then the part is different.
> 
> You are incorrect in your assumption it is the nature for these rear ends to be loud. Mine is as quiet as a church mouse. Every car or truck I have ever owned in my life was never loud. The car manufacturer does not build a car to be noisy. If there are noises coming from the rear it is not normal. Dana built a bunch of bad rears, some guys who have had their rears replaced got bad rears again. Some took 2 or 3 rears installed before they got a rear that was quiet.
> 
> ...



I liked my GTO but I was not willing to go through 3 rears to find a good one. 

After all it isn't like its a simple task to change them. Since it requires droping the craddle each time which in turn nessesitates a alignment. Which unless your dealership uses expensive alignment tools that attach to the hub or elsewhere you get a nice paint scuff on your wheel in four spots each time.

I am a perfectionist when it comes to my vehicles and will not deal with that much BS to get what I should have gotten to begin with.

As for noise all differentials make a noise be it one we hear or not. You can tune most of the audible ones out with a damper on the axle housing or driveshaft.


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## GTO JUDGE (May 14, 2005)

cody6.0 said:


> I liked my GTO but I was not willing to go through 3 rears to find a good one.
> 
> After all it isn't like its a simple task to change them. Since it requires droping the craddle each time which in turn nessesitates a alignment. Which unless your dealership uses expensive alignment tools that attach to the hub or elsewhere you get a nice paint scuff on your wheel in four spots each time.
> 
> ...


I like you am a fanatic with respect to care. I was real hesitant on having mine removed. It took a few hours and then an alignment. My worries were laid to rest. I have heard of not so fortunate dealings too. 

Dana has had MANY warranty problems over there years, some of that led to their filing for bankruptcy, along with CEO's bleeding the company...yada yada yada... I know many who have lost 10's of thousands in Dana stock. I watched their stock plummet, I sold my stock when they restructured and made money.

With quality people losing their jobs.... well....... quality went with them.


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## cody6.0 (Nov 28, 2006)

With the way things are anymore does a good part really exist anymore? 

Getting what you paid for and brand names don't seem to really matter with the GTO or most cars these days. 

I was pissed when I got my Vette and the steering wheel was just a little off center. I wasn't thinking how simple of a fix it was I was thinking dammit what rack will my car fit on and hope they don't f-up my wheels.


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## 05_GTO (Mar 1, 2006)

Whine is normal, believe it or not.


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## NJG8GT (Nov 14, 2007)

05_GTO said:


> Whine is normal, believe it or not.


I noticed today that when I eased off the goat she had a noise in the rear, but it didnt sound bad, it sounded like a bunch of power trying to slow down and ready to be launched at any second. I've always noticed a slight noise since mine was new. Year later and have 1,076 miles!


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## 05_GTO (Mar 1, 2006)

NJgoat said:


> I noticed today that when I eased off the goat she had a noise in the rear, but it didnt sound bad, it sounded like a bunch of power trying to slow down and ready to be launched at any second. I've always noticed a slight noise since mine was new. Year later and have 1,076 miles!


I've been though 2 rear ends, they both whined. These rear ends are just noisy, even my "updated" new rear end whines. You can put some Torco RGO 85w140 gear oil with a bottle of Torco FM to try to quiet it down. I do not suggest using Royal Purple IMO.


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## cody6.0 (Nov 28, 2006)

Truthfully I would be weary of using the Torco additive. Finding the right mix is hard not to mention it isn't made for a cone diff like the GTO's.

If you want to use non-synthetic to keep it quiet just use the GM additive.


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## LOWET (Oct 21, 2007)

PatrickNJ said:


> '05 A4
> 
> I noticed a slight whine when the car slows (letting off the gas completely or using the brake) down only in the range of 50 to 40 mph. I have 15,000 miles on the car and was wondering if anyone has a similar problem and what you decided to do.
> This may be related to reared whine but some of the members of this post say that it happens when they accelerate in the 40 - 50 mph range.
> ...


This might sound crazy, the sound you are hearing might be coming from your tires. Last year my car [ A/4 ] would make sort of a whine when slowing down. it drove me crazy. Turned out to be low air pressure in one rear tire


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## 05_GTO (Mar 1, 2006)

cody6.0 said:


> Truthfully I would be weary of using the Torco additive. Finding the right mix is hard not to mention it isn't made for a cone diff like the GTO's.
> 
> If you want to use non-synthetic to keep it quiet just use the GM additive.


Works good for me, much better than the GM crap. IMO


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## wutanga13x (Jan 22, 2008)

so..... what do you change the gm crap with? and how much torco additive did you use?


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## PatrickNJ (Apr 21, 2006)

*Update on Whine*

I took the Goat back to the delear last week and had the entire differential replaced. The service manager told me that when they spoke to GM they said that there have been problems with the diffs in the Goats. I am assuming they gave me the same type of diff.
After the new diff I do notice about an 75% difference (less whine).


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## 05_GTO (Mar 1, 2006)

wutanga13x said:


> so..... what do you change the gm crap with? and how much torco additive did you use?


I just put in the whole bottle of FM. I used Torco.



PatrickNJ said:


> I took the Goat back to the delear last week and had the entire differential replaced. The service manager told me that when they spoke to GM they said that there have been problems with the diffs in the Goats. I am assuming they gave me the same type of diff.
> After the new diff I do notice about an 75% difference (less whine).


GM has an "updated" rear end they replace the old ones with. What is updated I have no idea. GM can not "bandage" up the rear ends, so they have to replace them.


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## GTO JUDGE (May 14, 2005)

The rear end is swapped out and replaced with a new one. Sometimes the whine is completely gone, sometimes the whine is reduced, and sometimes the new rear has to be replaced with yet another new one.

This is not GM's fault, Dana Corp built a bunch of bad ones. The entire rear end is a Dana product. Dana has to make this part good, NOT GM. GM does the work, but will not tear apart a vendor's part. If the rear end was a GM product, it may be they'd tear it apart and rebuild one, however only GM would be able to verify this.

For anyone who doesn't know the process; Once the defective part, for instance in this case, a rear end, is replaced, GM will send it back to Dana, with a HEFTY back charge. They log hours it takes the tech to swap it out, and any other charge they can tag Dana with for a warranty claim. GM will make money on this. This keeps vendors on their toes when supplying a builder with parts. 

Once Dana receives the defective parts it is examined and noted, and any improvements that can be made are implemented in the build process. If Dana finds parts in that rear end are defective, they will back charge their supplier, even a sister Dana plant. I don't know who all supplies Dana with interior parts but each Dana plant is responsible for quality control, and if a fellow Dana plant is back charged it reflects on that plant and can reduce QC bonuses etc. 

My experience in warranty work with Dana was, and this was common with back charges with Mack Trucks.... Once the returned part is completely processed, that part is destroyed and sold as scrap. Seems like a huge waste but this is what happens. Parts within a unit that are not defective are sometimes purposely destroyed and placed in a scrap container so that part can not find its way into one of the employees garages and sold. Some parts after careful inspection are put back in inventory and reused. In essence, the defective parts are recycled. This is what happens when parts are replaced within warranty, or at least this is Dana's process. I have seen some really nice parts headed to the scrap heap, and anyone caught helping themselves to these parts was disciplined or terminated.


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## 05_GTO (Mar 1, 2006)

The rear end was not designed or made by Dana originally. It's a Borg Warner Model 80 IRS, which now belongs to Dana. So I guess you can kind of say it's a a Dana.


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## GTO JUDGE (May 14, 2005)

Dana Corporation's Independent Rear Suspension Module Drive Reintroduced, Nostalgic American Muscle Car


Dana Corporation's Independent Rear Suspension Module Drive Reintroduced, Nostalgic American Muscle Car

DANA CORPORATION LOGO
Dana Corporation logo. (PRNewsFoto)[AS]
TOLEDO, OH USA


TOLEDO, Ohio, Jan. 7 /PRNewswire-FirstCall/ -- Dana Corporation (NYSE:
DCN) announced today that it will supply the complete independent rear
suspension (IRS) module, including a Dana axle and limited slip differential,
and assemble front corner modules on the high-performance, V-8 rear-wheel-
drive 2005 Pontiac GTO.
(Logo: Newscom Search )
"Through our 100 years of experience, Dana has earned a solid reputation
for delivering drivelines that operate comfortably and consistently in
demanding environments. When automotive engineers need durability,
reliability, strong product design, and engineering knowledge for high-
performance applications, one of their obvious supplier choices is Dana," said
Bill Carroll, Dana's acting president and chief operating officer.
Rather than serving simply as a stand-alone component, Dana's axle was
designed into a complete IRS module. GM and Dana engineers found efficiencies
by borrowing from the GM Holden Commodore, Dana's first high-volume IRS
module, and applying the module to the new Pontiac GTO.
The differentials and axle assemblies are produced at Dana's Fairfield
facility in New South Wales, Australia. Dana's stamped rear trailing arms are
manufactured at Cheltenham, Victoria, Australia, suspension facility. Both
axles and trailing arms are then shipped to Dana's Adelaide, Salisbury,
Australia, facility for assembly into the complete IRS module. The IRS module
and front corner modules are then shipped to GM Holden's Elizabeth Vehicle
Assembly Plant where the Pontiac GTO is assembled and then exported to the
United States. The axle utilizes Dana's proprietary technology in hypoid gear
design that maximizes gear strength capacity and durability, as well as
optimizing gear tooth meshing refinement.
These Dana axles are more compact, requiring less packaging space in the
vehicle. The advanced axle design, along with publicly recognized
manufacturing quality, assures a reliable product for this powerful sports-
coupe application.
Dana also supplies the piston rings, cylinder-head gasket, and secondary
seals and gaskets for the vehicle's 5.7 liter V-8 engine.
Dana Corporation is a global leader in the design, engineering, and
manufacture of value-added products and systems for automotive, commercial,
and off-highway vehicle manufacturers and their related aftermarkets.  The
company employs approximately 60,000 people worldwide. Founded in 1904 and
based in Toledo, Ohio, Dana operates hundreds of technology, manufacturing,
and customer service facilities in 30 countries. The company reported sales
of $9.5 billion in 2002. Dana's Internet address is http://www.dana.com


SOURCE Dana Corporation


*As far as the 2004 year, no mention is made of the rear end. I have read where some think Borg Warner made the rears, however I cannot find any documentation from Borg Warner or GM stating the rear in the 2004 GTO is a Borg Warner product. The rear end is the same for all 3 years and the parts are interchangeable. For Dana to assume the build process, Dana would have had to acquire Borg Warner or buy the patent from Borg Warner to produce the rear ends. *


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## btchplz (Mar 12, 2005)

*Rear End Whine*

OK, looking for some advice. I've read about the rear end whine and always considered myself fortunate because I never experienced any problems with it. However, I just recently took in my car for service, they did a bunch of things and one was the rear end differential service.

During this service, they found a pinion leaking (If someone would please explain this to me that would be great). So I authorized them to fix the leak. They performed the differential service, and when I drove off. I noticed a howling sound as I coasted. Usually 30 MPH or more. I didn't turn right around because I picked up the car after hours. When I called the next day, they told me that the technician probably forgot to put in the additive that quiets the rear end. They told me to just bring it back and they would take care of it.

When I took it back this morning, my service writer pulled up the previous service order, and he saw that they did in fact put in the additive. But they would still check it out. So he calls me and tells me that the noise is definitely too loud to be a simple whine. He says the tech told him that due to the pinion leak, it could have caused damage to the gears and the whole rear end needs to be replaced because GM doesn't have parts for the rear end. After reading this post I can see why. He left it as he is going to have his service manager speak to GM to see if they can cover the replacement. I am way out of my warranty so I am nervous that I may be stuck with the $4200 bill.

What do you guys think of the situation, what possibilities are there that GM would replace it out of warranty? I have been servicing my vehicle regularly with the same dealer, and I am pretty sure this is the second Rear End differential service that they have performed. My car has 62K miles on it now.

If GM does not cover it, would the car be OK to drive with my annoying howling sound? I appreciate any comments or suggestions.

Thanks!:cool


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## GTO JUDGE (May 14, 2005)

This sounds like a classic case of you caused the noise, now you fix it. I'd stand fast on that. The rear is a sealed unit. If the pinion was leaking it was coming from the unit itself. By fixing the leak (putting a new gasket on I assume that's what they did, should not cause a howling noise)

It depends on what the tech did to fix the leak, did he tear it apart and not put it back right? If he took any gears out and put them back without proper backlash tolerances the gears may not be meshing right and you are hearing the results. 

Did they use synthetic gear oil? Did they use the correct weight oil? Did they under fill the oil?

I do recall when my rear was howling and the old oil was replaced with new, After a couple of hours the howling subsided.

Damage done to the gears? Only if no oil was coating them and heat got to them. Wearing can cause howling too but at 62K, unlikely.The howling only occurred after the tech serviced the unit. That analogy doesn't make sense. 

Your service department should make this right.

*Here is some information I found;*

"Many things can go wrong inside a differential. Although the hints are often subtle, most impending failures give fair warning in the form of noise.

Several situations can create ring-and-pinion noise. If the gears have been quiet and begin to howl, they are probably worn or wearing. If the gears howl during deceleration only, it’s possible that the pinion-bearing preload has loosened. Howling under acceleration at all speeds indicates that something in the differential -- gears, pinion or carrier bearings -- has worn or no longer keeps the gear alignment correct. If the gears howl while accelerating over a certain speed range, but not all speeds, it’s likely that the gears are worn due to lubrication failure or overloading. When a newly installed gear set howls, suspect the design or setup.

A common problem is worn carrier bearings, as indicated by a low-pitch rumble above 20 mph. On vehicles with C-clip axles the noise may vary while negotiating turns. Worn pinion bearings can cause whirring noises at all speeds, under deceleration and/or acceleration. Pinion bearings tend to whir, rather than rumble because the pinion is turning several times faster (depending on gear ratio) that the carrier. Badly worn bearings can also cause howl if they do not support the gears correctly.

Worn wheel bearings can be difficult to determine. A very bad wheel bearing typically makes itself heard with great clarity; it’s the bearing that is going bad, but not destroyed that is hard to find. Turning back and forth from hard right to hard left can identify the culprit; however, I’ve been fooled by right-front wheel bearings that make noise when turning right (which heavily loads the inside-left-front wheel bearing, but also loads the outside-right-front bearing).

One common situation that may not make any noise: The pinion spins, but the tires don’t rotate. Broken spider gears can render the differential immobile, and usually make a loud, crunching sound as they make their final departure. A broken ring gear will allow the differential to propel the vehicle for about eight feet at a time, then bang or grind as the section with broken teeth tries to engage the pinion. Depending on ratio, a broken pinion tooth (or teeth) will clunk about every two or three feet.

A broken axle is easily determined. After it breaks, a C-clip design axle can be pulled out of the housing without unbolting anything -- or may even find it’s own way out. On many bolt-in-design axles, the wheel will give the broken axle shaft away by cambering in at an angle.

A high spot on a gear tooth may sound similar to a broken gear, but will only make noise while accelerating or decelerating, since the spot appears on just one side of the offending tooth. A high spot on the ring gear will make a heavy clicking sound about every eight feet; a high spot on the pinion makes noise every two or three feet and is much more pronounced due to its higher frequency.

Whether large or small, differential noise is telling you something. Listen carefully! If in doubt, pull off the cover or remove the third member for a closer look. Catching a bad part before is ruins others is definitely worth the effort."


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## btchplz (Mar 12, 2005)

This info helps a lot, the service writer called me back and said GM will only charge me a $500 deductible to replace the whole rear end. I have asked him about the oil used and how the leak was fixed, he's going to get back to me.

Not sure how much can be done because my warranty has expired, but we shall see what he comes back with.


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## cody6.0 (Nov 28, 2006)

They did actually fix the leak though?

One of the most common misconceptions when doing a pinion seal is that you can remove the pinion nut remove the yoke, replace the seal and put it back together and it's fine. 

When in reality once you loose preload it's gone unless a solid pinion spacer is used. After a crush sleeve is relieved of pressure it is done working unless you crush it further which would lead to problems.


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## btchplz (Mar 12, 2005)

Well I think it's a little late to check how the fixed the leak. I already had the rear end replaced, but I have to tell you. A lot of things wrong that I thought were the transmission ended up being corrected by swapping out the rear end. 

I used to get a grinding feel when I would start to move in first. Now it's completely gone. I also used to get this clanking sound when releasing the pedal while driving in reverse. That's also gone. That just goes to show that anything that is out of the normal, you shouldn't dismiss as non important.

I think I was very fortunate that I only had to pay $500 to replace it. Lesson learned.


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## GTO JUDGE (May 14, 2005)

btchplz said:


> Well I think it's a little late to check how the fixed the leak. I already had the rear end replaced, but I have to tell you. A lot of things wrong that I thought were the transmission ended up being corrected by swapping out the rear end.
> 
> I used to get a grinding feel when I would start to move in first. Now it's completely gone. I also used to get this clanking sound when releasing the pedal while driving in reverse. That's also gone. That just goes to show that anything that is out of the normal, you shouldn't dismiss as non important.
> 
> I think I was very fortunate that I only had to pay $500 to replace it. Lesson learned.


Some are opting to leave the rear end alone even though they are hearing a distinct whine or other issues. Some don't want the hassles of getting a new rear end or think that nothing will become of it.

It isn't clear if no problems will arise from the whine or if other problems will result as a byproduct of this. If GM is replacing these rear ends under warranty and people choose not to go through with it, it could end up costing more than what you paid down the road.

Glad your issues were taken care of.


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## btchplz (Mar 12, 2005)

GTO JUDGE said:


> Some are opting to leave the rear end alone even though they are hearing a distinct whine or other issues. Some don't want the hassles of getting a new rear end or think that nothing will become of it.
> 
> It isn't clear if no problems will arise from the whine or if other problems will result as a byproduct of this. If GM is replacing these rear ends under warranty and people choose not to go through with it, it could end up costing more than what you paid down the road.
> 
> Glad your issues were taken care of.


If anyone else experiences something similar and are within warranty, I strongly recommend having it looked at and replaced if necessary. I would also look into buying the extended warranty.


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## PatrickNJ (Apr 21, 2006)

*Rear End Whine revisited*

I had my rear end replaced and I still get the same noise slowing down (from 50 to 40 mph) I also get a growling-rumbling noise when accelerating from 40 to 50 mph. Going to take it back again.

*With these similar problems that we have how can you tell that the problem is stemming from the rear end differential and not the transmission? *


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## GTO JUDGE (May 14, 2005)

PatrickNJ said:


> I had my rear end replaced and I still get the same noise slowing down (from 50 to 40 mph) I also get a growling-rumbling noise when accelerating from 40 to 50 mph. Going to take it back again.
> 
> *With these similar problems that we have how can you tell that the problem is stemming from the rear end differential and not the transmission? *


I have heard of some owners having to have the rears replaced several times before they got a "quiet" one. Some report still having some "slight" whine. 

As far as telling if it's coming from the rear and not the transmission... I am not sure while driving but with the service bulletins coming from GM, the symptoms indicate rear end issues. I would request changing the oil out and new synthetic oil with the friction modifier installed at the dealer be the first step to see if this quiets it down and if not then another change out would be next. 

Having the car with it's back end of the ground while the car's gears are engaged while someone is listening to the rear with a stethoscope they will be able to narrow it down.


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## PatrickNJ (Apr 21, 2006)

Thanks, That's what I fugured.
As far as the type of diff fluid what would you suggest, Royal Purple?


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## GTO JUDGE (May 14, 2005)

PatrickNJ said:


> Thanks, That's what I fugured.
> As far as the type of diff fluid what would you suggest, Royal Purple?


Some guys swear by this. If the Rear is under warranty I seriously doubt they will use Royal Purple. If you are doing the work yourself then that may be a good alternative.

Make sure you siphon out all the old oil. I worked for Dana many years and I can tell you, unless customers ask for certain fluids, Dana will not always use the "good stuff."


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## PatrickNJ (Apr 21, 2006)

Well I am going to take it back again and see what they will do.
If it's just a matter of flushing and changing out the fluid with something different then I am all for it. I have a feeling they will try giving me another diff. I will let you know what happens.


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## MJGTOWISH (Jun 15, 2006)

I hate to bring this from the dead but,

is there a aftermarket upgrade to fix this issue? I'm doing the pedders street kit 2 sawp and a bunch of little stuff. and when usng RP oild should i use a friction modifer if so what kind?


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## keebler28 (Oct 16, 2009)

I had the same issue with my 99 Mustang GT. It had quite few more miles on it than you have on the GTO but idk, any suggestions help?  I talked to my mechanic about it and he was fairly certain it was an issue with my rear differential - my pinion bearings were getting worn.

"Several situations can create ring-and-pinion noise. If the gears have been quiet and begin to howl, they are probably worn or wearing. If the gears howl during deceleration only, it’s possible that the pinion-bearing preload has loosened. Howling under acceleration at all speeds indicates that something in the differential -- gears, pinion or carrier bearings -- has worn or no longer keeps the gear alignment correct. If the gears howl while accelerating over a certain speed range, but not all speeds, it’s likely that the gears are worn due to lubrication failure or overloading. When a newly installed gear set howls, suspect the design or setup."

Check out Diagnosing Drivetrain Noise for some more information on this... 

Hope this helps.


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## keebler28 (Oct 16, 2009)

MJGTOWISH said:


> I hate to bring this from the dead but,
> 
> is there a aftermarket upgrade to fix this issue? I'm doing the pedders street kit 2 sawp and a bunch of little stuff. and when usng RP oild should i use a friction modifer if so what kind?


You could always replace 3:55's with 3:73's or if you're really looking for some power, the 4:11's.


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