UPDATED WITH RATTLE VIDEO**WHAT is this noise? 2024 Silverado 1500 WT, 5.3

s10dragracer888 · January 29

***UPDATE***

Engine tick was diagnosed as potential wrist pin or retaining clip failure. Severe scoring found on wall of cylinder number two. Engine is being replaced and should be up and running by the middle of next week.

The rattle was diagnosed as torque converter engagement at low vehicle speed, lock-up with DFM engaged. About 5th gear. They have another 2024, 5.3/10-speed (4,000 miles) that rattles in the same fashion. They’re thinking a software update to disable DFM at low speeds would be a likely fix (does not do it when all 8 cylinders are engaged). Further info will be provided when engine is replaced; a GM engineer is going to pay the dealer a visit for my truck to see if adjustments to the programming is necessary.

***uploaded this linked video for TCC sound***

Truck has 570 miles on it. It’s a 2024, 5.3, MHT 10 speed, crew cab short bed work truck. The other day, I was coasting (between 15 and 25 mph) and heard this loud, repetitive metal knock or tap sound under very light throttle. Sounded like it was coming from the engine bay, through the floor, approximately center or slightly to the right from driver seat POV. It came and went when I was very lightly engaging/disengaging the throttle pedal. It does not happen when I’m accelerating or when the drivetrain is under load. This morning, on start up, I hear this unusual metal “clack” that seems random in interval, but consistent nonetheless, at idle. My coworker drove beside me, and through the usual DFM noise, he heard the metal “knock” or “tap”, very loud, from the engine bay, while cruising and very light throttle. When I got to the dealer to drop it off, I couldn’t replicate any of the issues. Of course. I sent these videos to the service advisor, because he was stumped like I was.

Edited February 5 by s10dragracer888
Diagnosis from dealer provided and organization of material in post.

PunchT37 · January 29

Mine does the same thing since new. `25, 5.3. Goes away when hot.

newdude · January 29

Sounds like a lifter not pumping up all the way with oil.

s10dragracer888 · January 29

29 minutes ago, PunchT37 said:

Mine does the same thing since new. `25, 5.3. Goes away when hot.

Oddly enough, I have the same issue.

s10dragracer888 · January 29

19 minutes ago, newdude said:

Sounds like a lifter not pumping up all the way with oil.

I took it to the dealer. I’ve heard of issues with the camshaft timing actuator gear and timing chain tensioners in these, too. Under very light throttle (barely pressing the accelerator) at 15-25 mph, it makes an awful racket.

s10dragracer888 · January 29

41 minutes ago, PunchT37 said:

Mine does the same thing since new. `25, 5.3. Goes away when hot.

Also, the rattle I was hearing when driving happens at any temp, under the same exact conditions every time. This was a new condition that started this morning.

Edited January 29 by s10dragracer888

PunchT37 · January 29

The ticking sound does not match a lifter. The regular timing is off.

s10dragracer888 · January 29

Just now, PunchT37 said:

The ticking sound does not match a lifter. The regular timing is off.

I’m thinking more along the lines of chain slap or tensioner issue in the timing set. Could also be cam timing sprocket.

PunchT37 · January 29

I think it’s trans solenoids.

s10dragracer888 · January 29

7 minutes ago, PunchT37 said:

I think it’s trans solenoids.

Unfortunately, in my case, it comes from the engine. Transmission would be from directly underneath, right? This batch of noises comes directly from the engine bay. All of them.

PunchT37 · January 29

Even though I’m out of the business now, I did have around 25 yrs in the shop. I’d like to think I still have some troubleshooting skills.

PunchT37 · January 29

5 minutes ago, s10dragracer888 said:

Unfortunately, in my case, it comes from the engine. Transmission would be from directly underneath, right? This batch of noises comes directly from the engine bay. All of them.

I thought that too at first. Listen carefully. I don’t think it’s the engine.

s10dragracer888 · January 29

20 minutes ago, PunchT37 said:

I thought that too at first. Listen carefully. I don’t think it’s the engine.

Thank you sir, I’ll let you know what the dealer says.

newdude · January 29

2 hours ago, s10dragracer888 said:

I took it to the dealer. I’ve heard of issues with the camshaft timing actuator gear and timing chain tensioners in these, too. Under very light throttle (barely pressing the accelerator) at 15-25 mph, it makes an awful racket.

The most current version of this covers to 2024 - 19-NA-218 1..3

I listened to your video again. Definitely is engine related. Lifter not pumping up, broken valve spring, bent push rod.

GM has an audio clip in TSB 23-NA-170 of bad crank bearing and its not an intermittent noise like what you've got going on at idle in your clip. Its a constant noise. So I don't "think" your issue is lower end. 23-NA-170 1..3 Dealer can pull up the audio file in the TSB.

They can run a power balance per PI5832A to see if it can isolate to a top end or bottom end noise - MC-11007011-0001.pdf

It does not sound transmission related as others have suggested. There is a TSB for 10 speed noise concerns with audio files that the dealer can pull up. The noises are very specific and are gear, bearing or fluid level related. TSB is 24-NA-264, service dept. can play the audio.

Edited January 29 by newdude