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Posted

2013 GMC Sierra 5.3 LC9. I have a lifter or something ticking, but no misfire or other symptoms. Could this just be a loose rocker?  I seem to notice it more at first startup of the day when the engine has cooled overnight. The AFM has been disabled, I think, I bought the truck used, but it never goes out of V8 mode. Any thoughts? Any experiences like this? Thanks in advance.

Posted

Given the year I assume she has some miles. Lifter tick can happen to any hydraulic lifter. A little wear. A little gum or varnish and they bleed down faster than they use to. If the oil pressure is still really good a flush sometimes will free the sticky ones. BG ERP or something like it. Just follow the instructions. 

 

If you don't like flushes you can mix 5:1 some TRIAX S7 with your normal oil at the next change and run in as normal for 2K miles. It's an detergent in an oil carrier. Flushes are solvents and solvents won't remove carbonized deposits. Just say'n. 

Posted (edited)

I am not all that familiar with your year of Avi but I'm going to share my saga with you.

I developed the ticking lifter noise. I bought my truck with 86k miles on it. I'm thinking the ticking started at 1450k.

In my research I learned that the needles in the rockers make there way out of the lifters and appear in the drained oil during oil changes. My theory was that when the area where the lack of needles caused a gap there was a tick, so I replaced the suspected rockers, still had the noise. I also read the "O" ring on the oil pick up tube shrank with age and allowed the oil pump to cavitate and caused a ticking lifter sound. the book says to drop the front axle (4 X 4), oil pan, timing chain cover. remove the oil pick up tube and replace the "O" ring that seals the tube to the oil pump. Guys that say they are experts on the 5.3s say you can do this job without pulling the timing chain cover I donno, maybe. I replaced the pick up tube, and the oil pump (Melling units and I selected the High Volume pump) along with the "O" ring. I also found an additional clamp for the pick up tube. The pick up tube is held in place much like a distributor is on a small/big block or in line 6, A "U" shaped collar and bolt, the oil pump is drilled and tapped to accommodate another collar and bolt (available on amazon) so I installed it with thread locker. The book says to replace (no explanation on this) the timing cover. Since I was in there I replaced the timing chain and gear with a Melling double roller unit, I cleaned everything I could get at (Wal Mart spray brake cleaner is cheap and works as well as the $5.00 a can stuff) The tick is gone, my truck runs like a top, I get 20 avg. MPG when on the highway at 55 to 60 mph. My indicated oil pressure on a cold engine at idle is 55PSI and 45 at 60 mph. My compression measured 190 to 200 PSI; not bad for an engine with 180k miles.

Recently I replaced the ignition coil on the No. 8 cylinder, I got one off the neighbor's parts truck but have a new one on hand, I should buy a set (cheaper than buying 1 at a time) from PartsGeek.com or Amazon.

Edited by dna9656
  • Like 1
Posted
7 hours ago, dna9656 said:

I am not all that familiar with your year of Avi but I'm going to share my saga with you.

I developed the ticking lifter noise. I bought my truck with 86k miles on it. I'm thinking the ticking started at 1450k.

In my research I learned that the needles in the rockers make there way out of the lifters and appear in the drained oil during oil changes. My theory was that when the area where the lack of needles caused a gap there was a tick, so I replaced the suspected rockers, still had the noise. I also read the "O" ring on the oil pick up tube shrank with age and allowed the oil pump to cavitate and caused a ticking lifter sound. the book says to drop the front axle (4 X 4), oil pan, timing chain cover. remove the oil pick up tube and replace the "O" ring that seals the tube to the oil pump. Guys that say they are experts on the 5.s say you can do this job without pulling the timing chain cover I donno, maybe. I replaced the pick up tube, and the oil pump (Melling units and I selected the High Volume pump) along with the "O" ring. I also found an additional clamp for the pick up tube. The pick up tube is held in place much like a distributor is on a small/big block or in line 6, A "U" shaped collar and bolt, the oil pump is drilled and tapped to accommodate another collar and bolt (available on amazon) so I installed it with thread locker. The book says to replace (no explanation on this) the timing cover. Since I was in there I replaced the timing chain and gear with a Melling double roller unit, I cleaned everything I could get at (Wal Mart spray brake cleaner is cheap and works as well as the $5.00 a can stuff) The tick is gone, my truck runs like a top, I get 20 avg. MPG when on the highway at 55 to 60 mph. My indicated oil pressure on a cold engine at idle is 55PSI and 45 at 60 mph. My compression measured 190 to 200 PSI; not bad for an engine with 180k miles.

Recently I replaced the ignition coil on the No. 8 cylinder, I got one off the neighbor's parts truck but have a new one on hand, I should buy a set (cheaper than buying 1 at a time) from PartsGeek.com or Amazon.

 

Great read Doug. Question though. Those rockers you replaced; did the ones you removed indeed have missing needles? 

Posted

Make sure its not an exhaust leak before you start spending money or changing anything. Broken exhaust manifold bolts are very common and can sound exactly like a lifter or valve train noise,especially when the engine is cold.

Posted
On 9/16/2021 at 5:55 PM, mjm-1957 said:

Make sure its not an exhaust leak before you start spending money or changing anything. Broken exhaust manifold bolts are very common and can sound exactly like a lifter or valve train noise,especially when the engine is cold.


very true. If it only does this for a few minutes in the AM I would bet it’s this…

Posted (edited)
On 9/16/2021 at 2:34 PM, Grumpy Bear said:

 

Great read Doug. Question though. Those rockers you replaced; did the ones you removed indeed have missing needles? 

Thanks you I'm glad and hope it helps!

Yes I think so, you can see the needle bearing looking across the lifter from an opposite side; I saw a gap in there and I doubt they were made that way. The Mellings lifters I bought CAN"T loose a needle bearing because they are made more like a sealed bearing.

NOTE: I did not find any needle bearings when changing the oil but that doesn't mean I failed to notice it (them) nor were any in the oil pan that I had removed. Maybe they are made that way (with gaps between the needles) but I doubt it. The gap would rotate with the action of the lifter and when the gap reached TDC or BDC it would certainly have ticked according to my theory. But, what do I know....

Edited by dna9656
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