Noisy gmc 2500hd in 4 hi

[rtreptow7]

So I put my 2018 in 4 wheel drive for the first time today as it was snowing heavy. The thing was whining and noisy like I’ve never heard before. It sounded like I was driving a diesel. I had a 2017 truck too in the exact same model that was no where near this loud. In fact, I could not even hear the difference between being in 4wd or 2wd. There is no mistaking it in this 2018. I did some searching on the net and came across a service bulletin about a noisy transfer case that they claim is normal. But I don’t understand why the 2017 would be so quiet and this one so noisy? I’ll probably call dealer tomorrow and see what they have to say. Anyone else here experiencing this noise?

[gmcsmoke]

rtreptow7 wrote:


One of the many advantages of the new 2015 MY pick-ups is the cabin is quieter compared to previous model years. For that reason, when the vehicle is in 4WD mode (HI or Low), there may be some noticeable sound from the transfer case.

if the cab is quieter how can outside sounds seem louder?

-deep thoughts by jack handy

[rtreptow7]

The truck just turned 5000 miles and has plenty of warranty left. I did check the transfer case fluid and both front and rear differential and they were good. I'm going to make a point of using 4Hi more often this winter and monitor the noise.

[ChuckSteed]

Even though the “Techs” say it’s normal ...is it? Did they state if they...
... checked transfer case oil level
... checked front differential line level
... lift front tires off the ground and check both hub bearings for noise and wobble

You can do all the above yourself...and I’d recommend doing it

[ksss]

Depending on how close you are to your warranty expiring, I would run it and see if it gets worse.

[Dave_H_M]

My suggestion was to ride with the tech. I never let them on the loose.

Cuts the size of the pile of el toro poo poo down. :W

[rtreptow7]

Grit dog wrote:

rtreptow7 wrote:
I just got a call from the dealer and he had 2 different techs drive it and said the noise it makes is normal. They didn't have another truck there to compare it to. I should monitor it and bring it back if it gets louder or changes in any way.

A Chevy dealer had NO 3/4 ton 4x4s on the lot in the middle of Wisconsin??

Only dieslels.

[Grit_dog]

rtreptow7 wrote:
I just got a call from the dealer and he had 2 different techs drive it and said the noise it makes is normal. They didn't have another truck there to compare it to. I should monitor it and bring it back if it gets louder or changes in any way.

A Chevy dealer had NO 3/4 ton 4x4s on the lot in the middle of Wisconsin??

[Grit_dog]

eHoefler wrote:
Check your tire pressures. If the rear is over inflated for the load, they will be bigger in diameter than the front, causing the drive line to bind, especially if on dry ground or pavement.

Not really unless the other tires were half flat....maybe.

[rtreptow7]

I just got a call from the dealer and he had 2 different techs drive it and said the noise it makes is normal. They didn't have another truck there to compare it to. I should monitor it and bring it back if it gets louder or changes in any way.

[Jimbee]

My 2015 2500HD makes very little noise in 4Hi. Definately bring it in for service as it's under warranty. Then you will have documentation of an issue should something big break, and they can't say you neglected the issue.

[Ralph_Cramden]

rtreptow7 wrote:

Dave H M wrote:
I would take the truck back in to the stealer and have therm go out with you and take a test drive. Then drive another one from the lot and compare.

I would think they would not be able to do anything but a warm and fuzzy on the telephone. :h

I have an appointment at 7am on Monday to do just that.

I absolutely hate dealership service departments. GM had issues with fuel gauges acting wonky back in the 90's. You never knew how much fuel you had in the truck as the gauge would read whatever it felt like reading. I had a punk service writer tell me that the reason the fuel gauge would do that is from putting cold gas in the truck. I asked him if it told me somewhere in the manual not to drive in the winter, or should I be boiling my gas before dumping it in there.

[rtreptow7]

Dave H M wrote:
I would take the truck back in to the stealer and have therm go out with you and take a test drive. Then drive another one from the lot and compare.

I would think they would not be able to do anything but a warm and fuzzy on the telephone. :h

I have an appointment at 7am on Monday to do just that.

[rtreptow7]

Ralph Cramden wrote:
FWIW my 2015 GMC SLE 2500HD, 6.0 4:10 doesn't make any noticable noise in 4H.
It's so quiet that other than feeling it bind on pavement in a turn or paying attention to the light on the knob, I have forgotten to take it out of 4WD a few times.

That TSB references 15's and 16's although I do not believe any changes were made to the drive train or transfer case for 17 or 18 unless they were done internally. I think you have something else going on.

https://gm.oemdtc.com/7559/whine-noise-operating-in-4wd-2015-2018-chevrolet-silverado-gmc-sierra

Looks like it says it covers models 2015-2018. But again, my 2017 2500 hd was quiet, nothing like this. But this does describe exactly how my truck sounds. I'm guessing they are going to tell me it's normal, but I'll find out Monday.

[Dave_H_M]

I would take the truck back in to the stealer and have therm go out with you and take a test drive. Then drive another one from the lot and compare.

I would think they would not be able to do anything but a warm and fuzzy on the telephone. :h