Noise after shutting down engine

[txsokie]

I have noticed over the last couple of days a pump or whirring sound 2 or 3 seconds after shutting my engine down from a highway drive (2019 AT4 6.2L).  It lasts for just a second or two but it is very pronounced.  Anyone else see this same issue?  I did read somewhere that when you open the door after the truck sets awhile you will hear the fuel pump priming which I do hear.  This sound is very similar but higher pitched and louder.

[Pyrojodge]

Is it possibly the electric parking brake?

[Supreme Pizza]

Brake booster electric vacuum pump? 

[bowtie2007]

Mine does it, a very high pitch noise for probably 20 seconds or so. It does it regardless if i set the parking brake or not. It is also a different noise than when i unlock and open the doors.

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[SS502]

1 hour ago, starman8tdc said:

Brake booster electric vacuum pump? 

I do not believe they have a vacuum pump any more but use a IBC module but I could be wayyyyy off base.

 

https://www.wardsauto.com/technology/gm-plans-vacuum-free-braking-next-gen-trucks-sources-say

[Supreme Pizza]

I have no idea. Just throwing out ideas. 

 

Could be an emissions thing?

 

Suspension leveling? 

[CAE AT4]

Mine makes a whirring noise that sounds a lot like the servo motors on a robotic arm. 

To tell if the sound is the parking brake, stand outside the vehicle by the rear wheels while someone engages and disengages the parking brake. You'll hear the the parking brake motors on the rear axle.

 

Since my driveway is sloped, the brake motors will engage automatically when I park.

[GMCustomerService]

On 12/10/2018 at 10:57 AM, txsokie said:

I have noticed over the last couple of days a pump or whirring sound 2 or 3 seconds after shutting my engine down from a highway drive (2019 AT4 6.2L).  It lasts for just a second or two but it is very pronounced.  Anyone else see this same issue?  I did read somewhere that when you open the door after the truck sets awhile you will hear the fuel pump priming which I do hear.  This sound is very similar but higher pitched and louder.

Hi, txsokie. We understand how frustrating this whirring sound must be for you. Feel free to send us a private message, if you need us to provide an additional layer of support while working with your dealership. We hope to hear from you soon.

 

Anthony J.
 

[gearheadesw]

Emission control equipment, venting gasses.

[RadioFlyer32]

I hear the same thing, and have not been able to find a correleation with any other system.

[Unclebud87]

I've heard mine do that as well. Hasn't done it in a few weeks though. Definitely a head turner when it does it lol.

[Diaz Elec Inc]

I have a similar noise going on upon opening the ignition switch to the off position. It’s as if something is resetting a servo moving something to a certain position 

[ILSilverado]

My diesel does it like an intermittent sucking sound.

[achoo1]

On 2/7/2020 at 2:46 PM, ILSilverado said:

My diesel does it like an intermittent sucking sound.

I have a 2020 Silverado 1500 with the 3.0 diesel. Only had it for 2 days but noticed these sounds when I shut the engine off. Wasn't sure if this was normal or not. Never had a diesel so don't want to look dumb and take it back to the dealership just to turn out to be something normal lol

 

 

[BurnsMax]

10 hours ago, achoo1 said:

I have a 2020 Silverado 1500 with the 3.0 diesel. Only had it for 2 days but noticed these sounds when I shut the engine off. Wasn't sure if this was normal or not. Never had a diesel so don't want to look dumb and take it back to the dealership just to turn out to be something normal lol

 

 

Thats normal.  EGR valve cycling after shutdown