weird whine

[fatvdub]

2000 explorer
4.0 AWD
115000 miles

so the whine is not there during Idol just under acceration and is also present when I take my foot off the gas, this has been going on for a while,
also I just notice sence the snow has come, after i put it in 4wd it and get on the gas it makes more noise coming from the front. I know its had to diagnois just a whine, should I take it in sense it is my daily driver? or just wait untill it blows up

 

[timlagios]

Does it make the sound only when you drive? If so i would look at your ring and pinion, I had a truck that did that and the nut came off the pinion while I was driving. Bout scared the pooh out of me....Wait scratch that it did scare the pooh out of me.

 

[fatvdub]

yep only while the truck is moving worse under load

 

[timlagios]

def check rear end fluid aand front end fluid. thats what i would check first. without actually hearing the noise