strange sounds up front!

[9C1]

I’ve got a 2001 Yukon XL with 65k miles on it (not 165k) and it’s 4wd. When driving at lower speeds, maybe 25-35 mph I hear a wuh, wuh, wuh sound and I am guessing it’s a bearing up front. That’s when it’s in 2wd. When I put it in 4hi, I hear a much more aggressive groaning at about the same speeds. That louder sound seems different and it goes away when I let off the gas. Am I looking at a wheel bearing up front? Should I be checking the front transfer case fluid? Thanks in advance for the help!

 

[9C1]

No words of wisdom for a newbie, eh?! Just want to get some advice before I spend $ to have a shop look at this. Thanks!

 

[ezdaar]

yess check diff fluid asap.

 

[ATL]

i have no experience with this, but makes more sense to check the transfer case IMO. if it was the bearing, the noise would speed related regardless of throttle positioning. itf it stops when u left off the gas, it sounds more load related. what i mean is it seems like it does it when under a load/when pulling, not all the time like a bearing would