Hello,
Ihave a 2001 Mercury Mountaineer 5.0 V8 AWD (78K) and have just started to hear a noise(and non-pulsing vibration)that seems to be related to the drivetrain. It starts at about 5MPH and increases with pitch (based on speed) until it I hit about 60 where it is less noticeable mostly because of the road noise.I can hear it when the vehicle coasts down the hill in neutral and it gets the loudest around 30MPH. I am thinking it has something to do with the differential (bearings?), although if I could confidently diagnose it myself,! would not be looking here for expert advice. Hopefully, someone can help me assess.....

Any ideas?

Thanks!

 

might be the wheel bearing. do you notice it through each shift? my 99 explorer had a similiar sound which was caused by the wheel bearing. @$600 for replacement of the set..

 

Yes, the noise/vibration is there regardless of which gear the truck is in. The changing pitch fo the noise leads me to believe it is something to do with the drivetrain though....

More opinions are welcome ....

and I'll be sure to post once there is a resolution and I can get back to enjoying my Mountaineer.

 

Does the noise change when turning around long bends? get quieter toward the left or right?. What i would normally do to diag a rear end noise verses a wheel bearing noise in a explorer is lift the truck up on the rack. get someone els to drive the throttle and brake. Then get the wheels turning. using a stethiscope listen to the bearings. and also the Diff. Both the rear wheel bearings and diffs go out alot on these trucks. Is some models you can stop one wheel and listen to the other wheel. the switch although it would like it may be wheel bearings from what you are describing.

 

Just had it professionally diagnosed. It was actually both front wheel bearings.

$650 Total

Thanks for your help!

...now if I could just get that check engine light to go off - O2 sensor....AAArgh!!