Engine Tick, Chevy LM7 5.3L 2007. Lifter?

[Oro_O]

We were working on my dad's 2007 Express van, tracing an A/C line leak. I noticed a distnct loud rapid ticking; it seemed to come from near the front of the valve cover on the left side. We were busy and I did not get a stethoscope out to localize it further. I made a video of it but I can't get it to link or embed correctly here.

Here is a youtube video that is identical to me and more distinct than my video since it's in an open engine bay on a Silverado and not the semi-covered van's bay:

https://www.youtube.com/watch?v=vyhl7N6WVbI

It does not sound like an exhaust leak to me but rather too mechanical. Safe to assume it is a lifter on likely cyl 1 or 3? The van has about 146k on it with strong maintenance history. It got conventional 5w30 on schedule at Jiffy Lube 2007 to 2015, then it got Castrol Edge 5w30 and is the current fill, 2,300mi on fill since last September. They are driving less frequently and short trips (both retired) so a synthetic switch seemed in order. I do not recall the sound at the last oil change last year this time and I have not been under the hood since then. I doubt I could have missed it last spring/summer. My dad is hard of hearing and cannot hear it.

Anyone know this issue on these engines and have a recommendation? I was thinking of going to a 10w30 FS High Mileage oil for a higher ZDDP and HTHS, these do not seem to be strengths of the Castrol now that I look at the numbers.

 

[UNC017]

Exhaust leak: the clicking will get louder on rev-up, quieter on coast-down, louder under load, quieter under coasting.

Lifter: clicking volume doesn't change with load.

Being that its a Chevy engine with nut-and-stud mounted rockers, my money is on a loose rocker (or dozen) that needs to be brought back in spec. Don't try to fix a mechanical adjustment with an oil change.

 

[Oro_O]

Originally Posted By: 440Magnum


Being that its a Chevy engine with nut-and-stud mounted rockers, my money is on a loose rocker (or dozen) that needs to be brought back in spec. Don't try to fix a mechanical adjustment with an oil change.



I'm not familiar with these engines. You need to adjust the rockers periodically? In a 2007?

Last vehicle I had that needed that was a 1976 Honda 750K SOHC (granted, I sold it just a few years ago).

I don't believe in ignoring mechanical issues, but am not experienced with this engine.

 

[ls1mike]

Originally Posted By: Or
Originally Posted By: 440Magnum


Being that its a Chevy engine with nut-and-stud mounted rockers, my money is on a loose rocker (or dozen) that needs to be brought back in spec. Don't try to fix a mechanical adjustment with an oil change.



I'm not familiar with these engines. You need to adjust the rockers periodically? In a 2007?

Last vehicle I had that needed that was a 1976 Honda 750K SOHC (granted, I sold it just a few years ago).

I don't believe in ignoring mechanical issues, but am not experienced with this engine.

No.
An exhaust leak is common. How many miles?

 

[UNC017]

Originally Posted By: Or
Originally Posted By: 440Magnum


Being that its a Chevy engine with nut-and-stud mounted rockers, my money is on a loose rocker (or dozen) that needs to be brought back in spec. Don't try to fix a mechanical adjustment with an oil change.



I'm not familiar with these engines. You need to adjust the rockers periodically? In a 2007?



Woops, that's an corporate LSx, isn't it? I saw "Vortec" on the engine cover and my mind went to "Smallblock Chevy."

Even the SBC isn't *supposed* to need periodic adjustment, but if the factory didn't set the preload right normal wear can sometimes make a tick develop, which can be adjusted out.

But my bet is an exhaust leak anyway... but you can tell that by the "load / no-load" difference in sound test.

 

[dailydriver]

Originally Posted By: 440Magnum
Originally Posted By: Or
Originally Posted By: 440Magnum


Being that its a Chevy engine with nut-and-stud mounted rockers, my money is on a loose rocker (or dozen) that needs to be brought back in spec. Don't try to fix a mechanical adjustment with an oil change.



I'm not familiar with these engines. You need to adjust the rockers periodically? In a 2007?



Woops, that's an corporate LSx, isn't it? I saw "Vortec" on the engine cover and my mind went to "Smallblock Chevy."

Even the SBC isn't *supposed* to need periodic adjustment, but if the factory didn't set the preload right normal wear can sometimes make a tick develop, which can be adjusted out.

But my bet is an exhaust leak anyway... but you can tell that by the "load / no-load" difference in sound test.



If it is NOT an exhaust leak, then it is wise to check the rocker arm pre-load and torque (22 lb.ft.) settings, and trueness of the pushrods (roll them on a perfectly flat surface to check) FIRST since they are easy to get to under the valve covers, and IF it is actually the lifters (most likely, sadly), the heads MUST come off to change them out on the Gen 3 & 4/LSxes.

 

[cdm1993]

For what it's worth we had a Suburban 2005 1500 with the 5.3 with a bad lifter tick. If it is a lifter tick in your situation you could go ahead and try Marvel Mystery Oil. That is what I did with that Suburban and the tick went away within an hour of driving. That was last year, and still no tick.

I also have a 1997 5.7 Vortec K 1500 that had a very bad lifter / rod (one of the two, could not distinguish which) ticking sound that was solved by putting in one quart of Marvel Mystery Oil and 4 quarts of normal PCMO oil. The tick also went away very quickly in this situation. This was several months ago, and the engine is still quiet.

I have always and still am skeptical of oil additives but MMO has worked well for me and you could give it a shot and it may work well for you.

 

[UNC017]

Originally Posted By: cdm1993

I also have a 1997 5.7 Vortec K 1500 that had a very bad lifter / rod (one of the two, could not distinguish which) ticking sound that was solved by putting in one quart of Marvel Mystery Oil and 4 quarts of normal PCMO oil. The tick also went away very quickly in this situation. This was several months ago, and the engine is still quiet.



I can distinguish which it was from halfway across the country: It had to be a lifter BECAUSE it went away. Rod knocks don't go away until the rod exits the side of the block or seizes the engine.

Lifter check valves can get sticky causing a normally adjusted (or preloaded in the case of shaft-mounted rockers or non-adjustable torque-down studs like an LSx) valvetrains to tick. That's one case where a light solvent can sometimes clear the noise (or even an "Italian tune-up). But I don't hear that very often in modern engines with modern oils (or even old engines with modern oils).

 

[Oro_O]

Originally Posted By: 440Magnum

I can distinguish which it was from halfway across the country: It had to be a lifter BECAUSE it went away.


+1.

Thank you all for the information. I asked him to get a helper and see if varies at speed/load.

If it appears to be a lifter, I'll try MMO for a period. I have used it successfully on some of my vehicles and on some OPE. In fact there is an unopened quart of it in his garage, I bought it for him earlier this spring and told him to experiment with it in gas and to clean carbs in the OPE and motorcycles. I will update when we ID it and see what transpires.

 

[cdm1993]

Originally Posted By: 440Magnum
Originally Posted By: cdm1993

I also have a 1997 5.7 Vortec K 1500 that had a very bad lifter / rod (one of the two, could not distinguish which) ticking sound that was solved by putting in one quart of Marvel Mystery Oil and 4 quarts of normal PCMO oil. The tick also went away very quickly in this situation. This was several months ago, and the engine is still quiet.



I can distinguish which it was from halfway across the country: It had to be a lifter BECAUSE it went away. Rod knocks don't go away until the rod exits the side of the block or seizes the engine.

Lifter check valves can get sticky causing a normally adjusted (or preloaded in the case of shaft-mounted rockers or non-adjustable torque-down studs like an LSx) valvetrains to tick. That's one case where a light solvent can sometimes clear the noise (or even an "Italian tune-up). But I don't hear that very often in modern engines with modern oils (or even old engines with modern oils).




I now understand. Thank you for clearing that up.