Strange Drive line drone noise at 45 light light throttle

[Chuck B.]

Anyone know what this noise is? It's very intermittent. Seems to do it most often between 40 and 50 MPH cruising with maybe a slight up hill. Never does it on coast or heavy acceleration. Very hard to tell where it's coming from. 

20190521_191545_001.mp4

 

2014 Sierra Denali 1500

Crewcab, 5'8" bed

6.2 Litter

3.42 axle ratio

about 118,000 miles

Edited June 6, 2019 by Chuck B.
Add vehicle info

[508gm1]

I cant hear what you are describing. Do your rpm's normally jump around like that?

[silveradosid]

info on what type of truck and year

[Chuck B.]

On 5/24/2019 at 7:07 AM, silveradosid said:

info on what type of truck and year

Should have started with that.

It's a 2014 Sierra Denali 1500 with the 6.2. Crew cab, 5'8" bed, about 118,000 miles. 

 

On 5/23/2019 at 7:16 PM, 508gm1 said:

I cant hear what you are describing. Do your rpm's normally jump around like that?

The noise I'm hearing can be heard at 2 and 14 seconds in the video. 

 

I noticed the tach bouncing but was sure if that was normal for this truck or not. I'm climbing a slight hill in the video and the bouncing doesn't seem to be tied to the noise but it could be related. 

[Chuck B.]

I also put chassis ears on the truck and you can definitely hear the noise in the T-case and rear axle. It sounds different but the intensity is about even.

I did not hear the noise in the frame, exhaust, or front axle and it was hard to tell if I heard it in the transmission. 

[jmgardn2]

@Chuck B.

 

I know this is an old thread, but I dont suppose you were able to figure out what the problem was?  My truck (2014 SLT with the 6.2) has been doing the same thing for years and is driving me crazy!

 

John