I have a 2000 Durango SLT 4.7 litter V8 (4 wheel drive).

My SUV just started whining about a week ago. I can here the whine when I accelerate to 30+ mph and gets louder as I speed faster.

I have check the frond and rear DIF fluid as well as trans and transfer case fluids.
I have pulled off the front tires and I don't see anything abnormal. I've tried to "wiggle" the wheels and there is no "play" in either wheel.
I've looked at the whole drive train looking for any "wet" spots, and have found none...All looks normal to me.
I've jacked up the rear wheels and started the vehicle and accelerated to about 60 mph and the whine is not present.
I have rotated the tires to see if that could help, but it didn't.

I got on the interstate when traffic was low and sped till I heard the whine. I switch lanes back and forth to try to hear a difference in noise, but it sounds the same.

I really don't know what else to check, if you guys could offer some advise before I have to send it to the shop, would be most helpful.

Thank you

 

do you get any change in pitch between acceleration vs coast? if so, this could be a pinion bearing.

would you call it a whine or a roar or a growl. roaring and growling could be bearing. i'm stumped on the whine. can you tell front or rear or center?

does it do it in both 2wd and 4wd, or only one?
i read that in 2wd, on jack stands, it didn't do it. can you feel anything bad when manually rotating front wheels?

without anything else, and if i had to just make a guess, i'd guess tires or front bearings. are they simple tapered bearings, or expensive hubs?

 

I also went into neutral while going down a hill while it was whining
I also put the SUV into neutral and turned off the engine while going down this hill again.
The whine remained the same.

When I rotated the front wheels, I didn't feel anything abnormal, or did I hear anything abnormal.

This SUV has less expensive hubs two wheel anti-lock (around the $160 range)

About the whine, it kind of reminds you of off-road mud grip tires riding on a really rough road.
On my SUV, I don't hear any difference in pitch if I'm on a old road or a freshly paved road.

 

the 2wheel abs hubs are not that expensive, sounds to me like you got the 4 wheel abs hubs, a quick check to napa online shows $124 for the 2wd hubs, but i have seen them even cheaper if you spend a little bit of time looking
http://www.napaonline.com/Search/Det...+50022+2022007

 

When was the last time your rear diff oil was changed? The friction modifier mixed with it will breakdown over time, which can cause your rear diff to make some ugly noises.

 

this is true if he has a limited slip rear differential, i did not see any reference to it (still worth checking to make sure)