What did GM change?

[15 Z71]

So I have a 15 Sierra with the 5.3 and my friend at work has an 18 Silverado with the 5.3. What did they change on the motor? His is so quiet when its idling you can barely hear it running. My 15 sounds like an old model T idling. I just cant believe how much more quite his is.

[Jacoby]

Nothing changed

[15 Z71]

19 minutes ago, Jacoby said:

Nothing changed

I guess I just got a noisy one. 

[Wiggums]

If you have 100,000 miles and he has 20,000 miles.. that would be true for all vehicles. Either that or you got a noisy one.

[JimCost2014]

2 hours ago, 15 Z71 said:

So I have a 15 Sierra with the 5.3 and my friend at work has an 18 Silverado with the 5.3. What did they change on the motor? His is so quiet when its idling you can barely hear it running. My 15 sounds like an old model T idling. I just cant believe how much more quite his is.

What is the "sound" that yours makes that is different? Wonder if you have a bad vacuum pump, or one that is going bad?

[Mikebtte]

Things wear out, alternator will start making more noise over time and also make more noise if an electrical load is applied, Belt tensioners are always quieter when new, type and brand for belt being ran will very, A/C compressor age plays a role. Look at your exhaust manifolds and make sure everything is still buttoned up nice and tight, Lifters will also start to make a little more ruckus over time. Lots of factors under the hood. GM may have even changed the electric fan style.

[15 Z71]

45 minutes ago, JimCost2014 said:

What is the "sound" that yours makes that is different? Wonder if you have a bad vacuum pump, or one that is going bad?

Just sounds like a clicking or ticking sound. Kinda like everyone talks about the direct injection sound. It sounds like its coming from drivers side from behind wheel. Truck has 44,000 miles on it. It runs good, but it has sounded like this from day 1 when I bought it with 7 miles on it. 

[JimCost2014]

1 hour ago, 15 Z71 said:

Just sounds like a clicking or ticking sound. Kinda like everyone talks about the direct injection sound. It sounds like its coming from drivers side from behind wheel. Truck has 44,000 miles on it. It runs good, but it has sounded like this from day 1 when I bought it with 7 miles on it. 

This is from the post in the troubleshooting section, So I have had my truck into Dealer on multiple occasions for what sounded like a lifter tick. This ticking noise was loudest in the morning first thing when starting engine. With the hood open it sounds like a lifter sticking and coming from under valve cover. You also can hear it through the drivers side wheel opening. Since the dealer has recently replaced all lifters I decided to go ahead and replace the vacuum pump. I purchased one from Amazon for $128.83 and a Lisle Stretch belt tool 59370 for $15.00.

ACDelco 12669488 GM Original Equipment Vacuum Pump and Lisle 59370 Stretch Belt Tool

Upon start-up the loud ticking noise is gone. I can still hear the injector noise but it is not very loud compared to this noise I have been chasing for some time now. We will see how long this new designed pump lasts. It does not look as beefy as the original but if there is no noise I will be very happy.

[jagabom (Esquire)]

My 17 - 4..3 is quieter then my 14 - 4.3 was.  Less DI ticking I think.

Jim

[BigBadSierra]

My 14, 16, 18 all sounded the same.  The 18 engine noise is more muffed when the shutters are closed.

 

[Donstar]

16 hours ago, 15 Z71 said:

Just sounds like a clicking or ticking sound. Kinda like everyone talks about the direct injection sound. It sounds like its coming from drivers side from behind wheel. Truck has 44,000 miles on it. It runs good, but it has sounded like this from day 1 when I bought it with 7 miles on it. 

You should still have some powertrain warranty.  If your engine is making sounds that are inconsistent with other similar trucks then you have a legitimate reason to have it checked out at your local GM dealer.  It wont cost you anything and may put your mind at ease.  They may say "it's normal" but you'll have your concerns on record in case your engine dies a week after the warranty expires.

[15 Z71]

2 hours ago, Donstar said:

You should still have some powertrain warranty.  If your engine is making sounds that are inconsistent with other similar trucks then you have a legitimate reason to have it checked out at your local GM dealer.  It wont cost you anything and may put your mind at ease.  They may say "it's normal" but you'll have your concerns on record in case your engine dies a week after the warranty expires.

Good point. Only problem is it's a hundred dollars for them to look at it. If they find something then I dont pay it. But if they say it's fine i have to pay it.