Hi All,
As many know I just bought a very nice used 2003 Edge 3.0 automatic with 37,000 miles. Noticed today after a short 1 hour highway trip that between 40-50 mph or thereabouts I can hear a high pitch whine and can control this noise by letting off gas or giving it a little gas.
It is not real loud at all but no mistaking it or not hearing it either. Is this the ring and pinion in the rear end? Does it need new gears, different oil or additive, or do they all do this and is normal?

Thanks very much for your professional input.
Bye

 

A whine in that speed range often is the rear axle. I would check the current fluid level to see if it has been run low, then drain the fluid and inspect its condition and the condition of the gears and bearings.

 

Hi Bob. Thanks.
I do know there is zero signs of any leakage anywhere on the rear axle and the truck has never had a warranty claim in it's life or any work done to it except the scheduled maintenance by the original selling dealer including the big 30K service.
I will check the rear fluid level.

 

Yeah, it would be good to do that before draining to know if it was possibly underfilled. Some dealers change axle lube at 30K even though it not part of scheduled maintenance under normal conditions. After you drain it, you could look for other problems like water contamination or metal shavings.

 

Does the whining increase with wheel speed or motor speed? It could be a few thing but this will help decide if the problem is before or after the tranny.

 

Increases with wheel speed. If I place in N while driving it stops.

 

It MIGHT help to put the rear on jackstands and have someone "drive" it while you carefully listen around the truck.

 

OK this comment make zero sense... sorry.... So if you are going 60 MPH and put the truck in N the noise goes away? If so it is most likly something on motor... Could you please clearify this for me before we go forward

 

Usually, an axle whine is loudest when the engine is driving the wheels. Ease into the throttle, it whines. Let off or put it in neutral, it lessens or stops.

It could be a something else but his symptoms are consistent with an axle whine.

 

If you let off the gas, wouldn't the whin continue as there is still preasure in the axle? I personaly have not had the axle whin, so I am not 100% sure.

Another thing to try is to put the vehicle in park, hit the gas, does it whin? This would eliminate the drive train, or point the finger at the drive train...

 

On the throttle, the ring and pinion contacts on one side of tooth faces, off the throttle, it shifts to the other. Because of the power applied, more wear or chatter will usually occur sooner on the "drive" faces as compared to the "coast" faces. The noisy R&P's that I've heard seem to be the most noticeable under light throttle, steady speed conditions.

 

Understand.... Interesting.. Wondering if an additive would resolve this problem?

 

Bob. You are dead on. What you have described is precisely what my truck is doing.
It is not screaming loud or real bad but definately makes a whine noise.

 

Have you tried an additive? AMSOIL makes one (that got an extra one of) that I wouldbe willing to make you a deal on, too see if this would resolve your problem.

 

Hi Charles,
Would it be compatible with the factory fluid? Also the gearing I have is the open 8.8 with a 4.10 ratio, not limited slip.
If so I would be interested.
Thanks.

 

Yes, everything should be compatible... It isn't just for LS rear ends. It is an additive to help withfriction and noise... I have never had anyone try it yet with the Whining noise that you are explaining... So i am kinda interestedin knowing if it wouldwork. Seding PM now.

 

I've had this same exact whine ever since I bought my truck. It is exactly what Bob and CP are describing. I was told it's ok and normal between those speeds or something like that.

 

my guess is u-joints.
i would take it to the dealership and have them look at it for warranty work.

 

i have that same noise. mine gets louder with speed and goes away when i let off the gas. i changed the fluid out with royal purple when i changed the cover not too long ago. i read somewhere it was in a lot of rangers

 

yup its a tsb for the manuals. http://www-odi.nhtsa.dot.gov/cars/pr.../tsbsearch.cfm
not sure if it applies to the autos. dont have time to look at all of them right now.

 

Did this resolve the problem?

 

nope. still there. im sure its my diff cuz in any gear over 50ish i can hear it. not sure when it started cuz i had my exhaust off at the cat so couldnt hear crap.

 

Can you share the TSB? I could not find it on the link you provided

 

Can you post the TSB Please?