>Well I ran it on jack stands with wheels on/wheels off and could detect no noise.
>Checked fluid levels and drain plugs for filings in front diff and transfer case.
>Replaced T case fluid.
>Driveshaft (front) u-joint is fine.
And the faint noise is still there,the service manual says that some gear noise is to be expected and in talking to a mechanic he says the same.
Maybe this truck is just too quiet when compared to my previous 4x4s.
I'll keep snooping and let you know if I find anything.I was hoping that another Denali owner might say "yeah mine does that too" and make me feel better but, that hasn't happened so far...thanks for the replys,Mike
Does this whine/noise happen only when taking a tight turn? And does it happen more on one side(when turning) than the other side? I'm just asking because I had a Buick Rendezvous that had the versatrak auto 4x4, in other words it was 4x4 but I didn't have a choice on when to kick it in, it did it on it's own. I could always tell when it kicked in, and upon turning with the 4x4 on my rear end whined really bad, like a constipated cow (sorry) I have no other way of describing it.
We took it to a mom and pop mechanic and was told we needed a new rear end(costs 2k). I looked on TV(different site) and seen about the rear diff fluid and how it should see regular maintenance. Well the gear oil I needed was $65 a quart and I needed 5
But found a cheaper route....changing the fluid and not getting a new rear end lol. However after the fluid which was zilch had been taken care of in both the T-case and rear diff, the noise was still there. I fixed it by selling the POS and getting an Envoy
I have not had ANY noises from any of my 4x4 gears (A4x4 4hi 4lo), I do hear a little bit of noise in 4hi and 4lo when turning as in 4x4 your turning radius is greatly decreased, but it is NOTHING compared to the Lemon I just sold. I can't tell you honestly what the noise was from, it could have been just normal whining from a grumpy 4x4 being made to turn a radius that was just to tight, or maybe it needed a new rear end, either way that thing was a huge waste. It had more problems in the rear end than Kim Kardashian, I couldn't take it anymore.
But just know that there will be some noise when turning having the 4x4 engaged, and you may hear more as it is a quiet running vehicle. If all else fails...well then, good luck!