Identify a box? [Noisy air ride suspension compressor]

[Obi-Wan-YJ]

Our 2016 Tahoe has a box of some sort attached to the frame inboard of the left rear wheel. It looks like it has some small hoses connecting it with the fuel filler. Occasionally--often when we first start the truck--that box makes a loud, rough, whirring noise. I wouldn't quite call it "grinding." It's been doing this for a while, but since it's hard to hear from inside the cabin, I tend to forget about it unless I'm hooking up a trailer.

We're leaving on a long road trip in a few days, and just started wondering whether this noise might indicate an imminent failure that could ruin our trip. Can anybody tell me what that device is and/or why it's making that noise? Is it part of the fuel system or emissions system?

 

[Thrust]

That sounds like your air suspension pump. Do a search on youtube and see it that's what it looks/sounds like.

 

[Obi-Wan-YJ]

Oh yeah, that's definitely it. Thank you! What are the consequences of letting that pump fail while we're 1000 miles from home? Does it just mean the ride is a tiny bit out of level? Will it be any rougher? We will have a good bit of stuff in the truck, but we won't be towing anything.

Here's a great video about replacing the pump:

 

[RST Dana]

Oh yeah, that's definitely it. Thank you! What are the consequences of letting that pump fail while we're 1000 miles from home? Does it just mean the ride is a tiny bit out of level? Will it be any rougher? We will have a good bit of stuff in the truck, but we won't be towing anything.

Here's a great video about replacing the pump:

Pop out the relay until you get the shock or shocks replaced. It is in the fuse box under the hood.

 

[Obi-Wan-YJ]

Pop out the relay until you get the shock or shocks replaced. It is in the fuse box under the hood.

I'm not worried about the noise. I'm worried about mechanical problems. Is it better to have it not running at all than to have it running when it's noisy?

 

[SpyShops212]

Oh yeah, that's definitely it. Thank you! What are the consequences of letting that pump fail while we're 1000 miles from home? Does it just mean the ride is a tiny bit out of level? Will it be any rougher? We will have a good bit of stuff in the truck, but we won't be towing anything.

Here's a great video about replacing the pump:

You could drive with a failed pump. I drove from Miami to New York with no issues. If you hear it when you first start the truck for a few seconds then it’s normal. You don’t always hear it when starting the truck in the morning but it’s normal. You will hear it if your loading the trunk with heavy items run for a few seconds or if you load up the truck with people. If you hear the pump constantly while driving then it is probably a disconnected or bad hose not the pump or shocks. If you hear the pump then it’s working so you don’t need to replace it. I replaced my two rear shocks in the past because I heard the pump running while I was driving often. After replacing my rear shocks I still was having the issue. I ended up replacing a small hose for $50 and my problem was resolved. I spend $1300 for no reason.

 

[SpyShops212]

Tell us exactly what it’s doing. Does it only run for a few seconds when loading or starting the truck? Is the pump constantly running? Let us is know the situation so we can advise you correctly. If the pump is constantly running then disconnect the fuse or relay. You don’t want to burn out the pump. I am betting that something got disconnected or the hose is bad. This is the part that goes bad

 

[Obi-Wan-YJ]

You will hear it if your loading the trunk with heavy items run for a few seconds or if you load up the truck with people. If you hear the pump constantly while driving then it is probably a disconnected or bad hose not the pump or shocks. If you hear the pump then it’s working so you don’t need to replace it

How loud should the pump be when it's working properly? If I'm standing upright back by the left rear wheel when it kicks on, the pump sounds louder than the 5.3L engine & exhaust. We've had the truck 3 years, and I don't remember hearing that even last year.

 

[Obi-Wan-YJ]

Tell us exactly what it’s doing. Does it only run for a few seconds when loading or starting the truck? Is the pump constantly running?

The pump runs for a little while now & then--often when you start the truck after sitting for a while. It runs for a lot more than a few seconds, but it's certainly not constant. It turns off eventually. When it runs, it's very loud. As I mentioned above just now, if you're standing by the left rear wheel, the pump noise overpowers the exhaust noise. Should it be that loud? I don't ever remember hearing it prior to this Spring.

 

[SpyShops212]

If you post a video or if you want to text me @ nine one seven, two five seven, one five nine four. I will tell you if it’s normal. I will send you back if you want to compare. There are sounds my 2018 Hybrid Camry makes that I did not notice until two years later. I found out it was normal after researching. You may have not noticed until now but it may have been happening the whole time or normal.