Metallic engine noise

[alvocado]

I know it's hard to diagnose engine noises via a video but I'll throw this out for the group to weigh in. Over the past couple of weeks, I've noticed what I would describe as a metallic/clacking noise from the engine. I can hear it while driving and it is consistent warm and cold and throughout the RPM range.

Here's a video at cold start under the hood. It's not a pronounced ticking but more like a valvetrain, metallic sound which concerns me. What would be the likely source of a grinding/clacking noise with 234k on the odo? I know there's some alternator whine as well despite recently swapping out the unit.

 

[LSxBakakos]

Its hard to tell from the video, almost sounds like an exhaust leak

Shot in the dark, old mechanics trick

Remove the serpentine and ac belt, fire it off and if the noise is still present then continue your search. Ive heard roached bearings in idlers tensioners make some sounds youd never think of

If noise persists take a long handled screwdriver and use it as a stethoscope. Pinpoint where its coming from.

Also perform a visual and verify no broken manifold bolts. You can use a mirror and or finger as the soot trick around exhaust manifolds and see if theres any soot that comes off, check manifolds for cracks too.

If under the valve cover, could've dropped the needle bearings in the rocker fulcrum

If its more so deeper in the block then it could be either lifters or wrist pins.

From what I can hear in the video it sounds more top end rather than lower and or lifters, but in person will tell the truth

 

[LSxBakakos]

In case it is more metallic and deeper(rods are hard tap/knock, mains are deep knock), loose torque converter bolts can replicate a bad rod bearing as well.

 

[Fless]

In case it is more metallic and deeper(rods are hard tap/knock, mains are deep knock), loose torque converter bolts can replicate a bad rod bearing as well.

Or a cracked flexplate.

 

[LSxBakakos]

Or a cracked flexplate.

Agreed, my 06 fragged itself around the crank bolts. Made no noise under load, on decel rattled like hell

 

[alvocado]

I believe the noise is upper engine and more noticeable on the passenger side. Both manifold gaskets were replaced earlier this year with ARP bolts installed. The sound from inside the truck is a metallic clacking noise. When you've had 234k miles of butt time in the same rig, something different is noticeable. I had the intake off when I did a rear main seal in July and checked the VLOM bolts which were pretty tight; only one had a little bit of room to torque down. Oil still looks clean with no signs of metal frag.

I know it's darn near impossible to capture a noise on video vs. what you hear live so I may have to monitor. If it is early lifter noise, I'll be faced with a decision: swap the lifters with OE parts or do a full AFM delete for 3x the cost. The truck is in great shape and I've invested $4k in parts this year alone not including a $4300 transmission rebuild. It doesn't burn oil and runs great aside from the recent engine noise.

 

[LSxBakakos]

I believe the noise is upper engine and more noticeable on the passenger side. Both manifold gaskets were replaced earlier this year with ARP bolts installed. The sound from inside the truck is a metallic clacking noise. When you've had 234k miles of butt time in the same rig, something different is noticeable. I had the intake off when I did a rear main seal in July and checked the VLOM bolts which were pretty tight; only one had a little bit of room to torque down. Oil still looks clean with no signs of metal frag.

I know it's darn near impossible to capture a noise on video vs. what you hear live so I may have to monitor. If it is early lifter noise, I'll be faced with a decision: swap the lifters with OE parts or do a full AFM delete for 3x the cost. The truck is in great shape and I've invested $4k in parts this year alone not including a $4300 transmission rebuild. It doesn't burn oil and runs great aside from the recent engine noise.

By any chance were they the delco original/MLS? The aluminum/graphite style normally dont last long. Buddy had that 8mo after his lifter replacement

If its a metallic clanking buy a oil filter cutter off Amazon, pop the top and bottom aluminum shielding off and accordian the filter material

Magnetic would indicate an issue with the cam and or lifter, non -ferrous would be the aluminum coating on a bi metal bearing, if theres stripper glitter/brass that means a bearing has left the chat

 

[donjetman]

@alvocado
Used engine oil analysis:
https://www.amsoil.com/p/oil-analyzers-test-kit-ups-pre-paid-oaiuppkit/
pay $20 and become a preferred custom for the discount

 

[alvocado]

By any chance were they the delco original/MLS? The aluminum/graphite style normally dont last long. Buddy had that 8mo after his lifter replacement

If its a metallic clanking buy a oil filter cutter off Amazon, pop the top and bottom aluminum shielding off and accordian the filter material

Magnetic would indicate an issue with the cam and or lifter, non -ferrous would be the aluminum coating on a bi metal bearing, if theres stripper glitter/brass that means a bearing has left the chat

I used the Felpro steel gaskets but they were quite different than the OEM steel that came out. They look like coated paper IMO. I'll test for manifold leaks to start.

@donjetman $20 is cheap for oil analysis. Blackstone Labs runs $40.

 

[alvocado]

I threw the shop vac in the tail pipe with hose on the vac outlet and sprayed some soapy water on the manifold. I have a bubble bath on the passenger rear and drivers front corners. I'll try to retorque the bolts and worse case, it looks like I'm changing gaskets this weekend. I opted for the Felpro assuming that the GM steel wouldn't seal as well with old exhaust manifolds but I might need to reconsider.

 

[Doubeleive]

I know it's hard to diagnose engine noises via a video but I'll throw this out for the group to weigh in. Over the past couple of weeks, I've noticed what I would describe as a metallic/clacking noise from the engine. I can hear it while driving and it is consistent warm and cold and throughout the RPM range.

Here's a video at cold start under the hood. It's not a pronounced ticking but more like a valvetrain, metallic sound which concerns me. What would be the likely source of a grinding/clacking noise with 234k on the odo? I know there's some alternator whine as well despite recently swapping out the unit.

do not hear anything specific, it does sound off in some manner
before you do anything, go down to the auto parts store or harbor freight and grab a $10 mechanics stethoscope and do a lot more inspecting
consider that a internal repair could cost you a few grand and so checking for the source of the noise is probably well worth your time and effort.
like noted already take both belts off and start it up, you can safely run it a minute or two at idle without the water pump running.
doing that rules out any bolt on parts. listen all over up top, front, bottom, cat's, oil pan, block, heads, starter, bell housing
you can pinpoint each cylinder from underneath or above

 

[alvocado]

Thanks, Wes. All good suggestions. the best way I can describe what I hear from inside while driving is a clacking sound a diesel truck makes when accelerating. I do have a scope so I'll spend some time tomorrow poking around when I retorque the exhaust manifold bolts.

 

[15burban]

When you did the exhaust manifold gaskets did you check and see if the manifolds themselves are flat and not warped?

 

[alvocado]

When you did the exhaust manifold gaskets did you check and see if the manifolds themselves are flat and not warped?

I replaced the drivers side manifold when I addressed the leak last Dec. It was cheap and I considered it could have warped due to the leak.

The passenger side was done early summer because of broken bolts and I didn't fully remove the manifold because my oil dipstick is rusted into the block. I extracted one bolt, broke an extractor off on the front bolt, then put it back together with a new Felpro gasket and a Dorman clamp on the front corner.

 

[donjetman]

@donjetman $20 is cheap for oil analysis. Blackstone Labs runs $40.

$20 is the cost of Amsoil preferred membership, not the cost of the kit.

 

[alvocado]

I had a scope on the cylinder heads, valve covers, etc. and have a question on what's normal since I don't have a baseline or other 5.3l to compare to. I can hear ticking on the valve covers, louder in some spots vs. others. Is this normal noise from the rocker arms or should there be no ticking/clicking hearable through the stethoscope when the rockers are fully secure with zero slop?

 

[Doubeleive]

I had a scope on the cylinder heads, valve covers, etc. and have a question on what's normal since I don't have a baseline or other 5.3l to compare to. I can hear ticking on the valve covers, louder in some spots vs. others. Is this normal noise from the rocker arms or should there be no ticking/clicking hearable through the stethoscope when the rockers are fully secure with zero slop?

topside has more moving parts and makes some noise, if it is not the noise you are hearing I wouldn't worry about it, I would be more concerned about the lifters which would be heard from the lower part of the head like under the spark plugs.
you can always request a oil sample kit from blackstone labs and send a sample in they charge I think $40-45 used to be $30-35, went up $10 a year or so ago.
that gives you the definitive answer on metal wear.

 

[Salvatore Fazzina]

I know it's hard to diagnose engine noises via a video but I'll throw this out for the group to weigh in. Over the past couple of weeks, I've noticed what I would describe as a metallic/clacking noise from the engine. I can hear it while driving and it is consistent warm and cold and throughout the RPM range.

Here's a video at cold start under the hood. It's not a pronounced ticking but more like a valvetrain, metallic sound which concerns me. What would be the likely source of a grinding/clacking noise with 234k on the odo? I know there's some alternator whine as well despite recently swapping out the unit.

Get a Mechanics Stethoscope and probe different parts of the engine to narrow down the location of where the sound is coming from. This will help your diagnosis. I suggest one with a long probe...I have a short probe and I have to climb half way into the engine bay to reach anywhere near the back of the engine.

 

[mikez71]

I had a scope on the cylinder heads, valve covers, etc. and have a question on what's normal since I don't have a baseline or other 5.3l to compare to. I can hear ticking on the valve covers, louder in some spots vs. others. Is this normal noise from the rocker arms or should there be no ticking/clicking hearable through the stethoscope when the rockers are fully secure with zero slop?

They never sound exactly all alike throughout the valve cover or even exhaust ports/intake ports on the older aluminum intakes, injectors.. I always hear some variance.
Might check injectors too for clicking at idle.. I can't hear anything odd in your video.

But by your initial description of metallic sound while accelerating, I wonder if you've replaced the starter yet?
Parts in there get real loose..

 

[petethepug]