07 Denali 6.2 Engine Noise

[black07denali]

My engine makes a noise that is most noticeable around 1500-1800 RPM's. It doesn't matter if you are in park or in gear, the sound is present. The sound is almost identical to the winding sound a manual transmission makes in reverse. It is like a buzzing/winding sound and the pitch gets higher with RPM's. It does not seem to affect the performance in any way but it is very annoying as it should not sound this way. Any help would be appreciated, has anyone else experienced the same thing? It has 75K on it and still has the remaining powertrain warranty but I thought I would start here to get some ideas before potentially wasting a trip to the dealership.

Thanks guys!

 

[Zed 71]

Has all the maintenanc been done like changing all the differential and tranny fluids?

 

[black07denali]

Has all the maintenanc been done like changing all the differential and tranny fluids?

All fluids have been changed regularly including a recent tranmission fluid change. It even had a torque converter replacement less than 5K ago, under warranty. It made the sound before that as well but I did not think to have that checked out when it was in for the torque converter repair.