steelcity

I had my hood latch/catch replaced at the dealer under warranty and my truck did the exact same whistle. I had to monkey with the adjustment to get the whistling to stop

Don't the SLT's come with leather seats and the SLE's cloth?

Happened on my 16 also. Hood latch replaced under warranty. Had to fiddle with the adjustment though, around 35 mph whistling noise from under the hood.

Calm down Francis, just replying to the OP's second post. He said he was wondering what others are doing about the auto 4wd select and I am answering.

You're right, his is a 1500

My son left his in "auto" and a "service 4wd" message kept coming up. Dealership said not to ride around like that every day on pavement, only when on dirt roads or such.

My 2016 has done it from day one. No biggie, just noticeable.

I got rid of my 2013 Avalanche just because of this issue!! Took a huge loss! How can GM help me now??!!

No. Windows up or down, sunroof open or closed, it sounded like the radio was on playing music very low. It was VERY hard to pinpoint for me but I adjusted the hood latch and lowered the hood a hair and it was gone. Only did it at certain speeds

I had the same noise, turns out the hood latch needed adjusted. Air was getting under the hood just enough to whistle. Once adjusted, no more whistle.

I thought the same thing but I wouldn't

GM truck sales are down 9% compared to this time last year. 1st quarter sales.

Mines off since it cracked in the snow

My 2016 2500 is the same way, bare metal and rusted. Built in August 2016.

Well, I'm going to answer my own question, lol. Dealer called and said GM just put out a bulletin and it states that the noise is from the internal transmission solenoids being commanded to minimum line pressure by the TCM. Noise is considered normal. Naturally. Just about every GM vehicle is affected from 2006 to 2019. They gave me a copy of the bulletin. Document ID : 5246136 #PIP4021D: High pitch whine or buzz heard from under the vehicle, dated 2-21-19.