whine in front end of 2010 4.6

[JeffS2010]

I recently bought a 2010 Explorer, V8 Eddie Bauer with just 87K on it, for just under $10,000. Thought it was a great deal. After driving just a couple hundred miles I'm hearing a whining sound at low speed (below 25) and low gear. Can't tell if it's located in the transmission or front differential. It stops when I let off the gas and when speed increases enough to shift gears. Any thoughts appreciated for this newbie.

 

[94Eddie]

The first thing to do ASAP is to check the fluid levels in the differentials, transmission and transfer case. This is to make sure you aren't running any of them dry, or low on fluid, which could lead to a very expensive repair. It could be a number of things from the CV joints, wheel bearings, gear issues in the differential etc. Do you see anything leaking fluid?

 

[06bluez]

also check your tires to make sure they are worn evenly. if they are mismatched you're gonna need new tires... difference in rotation speed can make the auto 4x4 kick in