Howl in 4WD When Decelerating

Hi all,

I'm hearing a loud howling sound whenever I'm in 4WD only when my foot is off the gas. When I'm accelerating or maintaing speed, there is no noise and everything sounds normal.

Any ideas? I'm not sure how to diagnose this.

Hi or Low range?

Mine does it all the time in Low range.

Your front differential is telling you it needs servicing or the pinion depth is set incorrectly.