Transmission Whine / Hum

[LukerDooker]

Wheel bearings will make a speed-related whine regardless of the level of 'gas' being applied even if the vehicle is coasting.

A differential whine usually happens under acceleration or during a stead-state operation. If you let up on the gas a differential whine usually goes away.

If this were a rear wheel drive vehicle, I'd suggestion having the differential fluid changed (about $200). I honestly don't know if this applies to the FWD or 4WD 2011+ Explorers.

This happened on my old Honda, they used the wrong type of fluid in the diff.-big no-no.
Also if doing a 360 turn in a quiet spot somewhere, the diff made a horrible groaning sound during the turn, as its being a bit stressed when doing a full circle.
But noisy only when doing a complete circle, not when turning less than that.

 

[roamingphantom]

Hi,
Just wanted to provide an update. After my visit to the dealer today I was told that I had a bad PTU and that one will be ordered on Monday. I had previously had a PTU seal leak which they had fixed.

Waiting now for them to place the order and do the fix. The service tech told me that they are aware of them going bad but not at 9k miles so we will see.