Whining Noise

[Mike1925]

2013 Ram Big Horn, have had this truck since new, love it! At 94K, I have developed a high pitched whining sound while moving, the pitch gets higher with speed. Have ruled out wheel bearings. Cannot tell where the sound is coming from, even with passenger(cert Mechanic) hanging his head out the window. Sometimes it sounds like it is coming from the rear, than the transfer, anyone heard of this?

 

[pacofortacos]

Have him put it up on a rack and listen to the pinion bearings.
High pitch is usually engine accesory - belt tensioner, etc
OR
Pinion bearings in the rear usually.

 

[hsousa88]

Developed the same noise on my ‘12... think it’s the idler pulley.

 

[Mike1925]

It's not engine accessory, goes up and down with the speed of the vehicle, we were leaning towards the rear. It sounds like the truck is in 4 wheel drive all the time(it is not).