Occasional light lifter tick starting

[dkad260]

2012 XL Denali, 130K miles.

Some history, long-winded but bear with me.

Oil pressure sensor and screen was replaced last year due to cluster gauge going wacky.

I bought this with about 82K miles, maintenance history was good, dealer oil changes every 5-7K.

I changed the oil when I bought it and ran Mobil 1 5W-30 and changed every 5K. At about the 118K-ish mile mark, I would hear a very light, occasional tick when pulling through a drive-thru, and would go away if I raised the RPM slightly.

I figured since this was near the end of the oil change interval, perhaps the oil was thinning, oil pressure on the gauge was just above the 20 PSI mark, idling, hot engine.

So I wanted to try some Redline 5W-30/NAPA Gold filter and that solved the hot, ticking issue, again, this was a random tick and nothing continuous.

Near the end of that oil change interval, which went a little long to about 6K miles, it started ticking again but this time it would be a random tick, like....tick,tick..........tick..........tick, tick, tick.....................tick,....etc. It sounded like the lifter was starting to varnish up and barely hanging up.

I changed that oil with another dose of Redline but had a M1 filter and this time the tick didn't go away at first, took about 500 miles. Then at the end of a 1000 mile road trip, and 2500 miles on this oil, the tick started again but was more consistent, and would go away if I raised the RPM to about 900-1000 RPM.

For the sake of science, I drained that oil and did a 5 quart Valvoline 5W/30 and 1qt MMO treatment, PF-63, then the next day I added 1 can of Liqui-Moly Hydraulic lifter additive.

The oil I drained with 2500 miles, had no metal, no flakes, but a small layer of a velvety-dusty goop and maybe what the last few oil changes was breaking up. Not alot, but maybe a couple finger tip amounts.

I currently have about 100 miles on the cleaning concoction of oil, MMO, Liqui-Moly.

The symptoms seem to be improving slightly. The tick usually doesn't happen until about 20 sec after I start the engine when hot, but sometimes it will happen right away.

If I raise the idle, it tends to stop.

If I shut the engine off and restart, it sometimes takes about 10-15 sec to start up.

I drove home from work, about 30 miles today and it was quiet. I let the engine idle for 20 min and it was quiet. I ran an errand today after it cooled and it came back at idle.

Sometimes it will tick at half cam speed, and stay very consistent.

This is hit or miss, but I have some questions...

Could this possibly be the O-Ring restricting some volume and not pressure? Or does a bad O-ring only drop pressure?

My hot oil pressure reading on the sensor displayed in Torque is 21-23 PSI at a hot idle, oil temps at 200-210 deg,.this is also with a slightly thin oil/MMO mix.

It sounds like it's either cyl 4,6,or 8, hard to tell, but on the pass side.

Engine runs fine, smooth idle and smooth power.

Not an exhaust leak or loosen spark plug wire, it almost sounds like a spark but definitely a lifter....again, high-pitched, light tick.

I'll get some videos posted shortly.

 

[dkad260]

This video is with the oil/MMO mix. After driving it, I shut it down then restarted, went over to the pass side wheel well and started the video, so maybe 10 sec elapsed after engine start

This is pretty much the worst it sounds when acting up.

 

[B-train]

Most likely the oil pump o-ring (I lived the same saga with a 2007 Denali). But, since you have the AFM, just make up your mind that you are doing an oil pum o-ring, valley gaskets/VLOM gaskets. Your oil pressure will be fine after that.....

 

[dkad260]

just make up your mind that you are doing an oil pum o-ring, valley gaskets/VLOM gaskets

So is this not just a pan removal, pick-up tube removal, then O-Ring change? Does the front cover need to be removed?

 

[dkad260]

This is my oil pressure reading through two short traffic lights. I tried to vary the RPM a little bit.

Pic of hot idle.

 

[Geotrash]

2012 XL Denali, 130K miles.

Some history, long-winded but bear with me.

Oil pressure sensor and screen was replaced last year due to cluster gauge going wacky.

I bought this with about 82K miles, maintenance history was good, dealer oil changes every 5-7K.

I changed the oil when I bought it and ran Mobil 1 5W-30 and changed every 5K. At about the 118K-ish mile mark, I would hear a very light, occasional tick when pulling through a drive-thru, and would go away if I raised the RPM slightly.

I figured since this was near the end of the oil change interval, perhaps the oil was thinning, oil pressure on the gauge was just above the 20 PSI mark, idling, hot engine.

So I wanted to try some Redline 5W-30/NAPA Gold filter and that solved the hot, ticking issue, again, this was a random tick and nothing continuous.

Near the end of that oil change interval, which went a little long to about 6K miles, it started ticking again but this time it would be a random tick, like....tick,tick..........tick..........tick, tick, tick.....................tick,....etc. It sounded like the lifter was starting to varnish up and barely hanging up.

I changed that oil with another dose of Redline but had a M1 filter and this time the tick didn't go away at first, took about 500 miles. Then at the end of a 1000 mile road trip, and 2500 miles on this oil, the tick started again but was more consistent, and would go away if I raised the RPM to about 900-1000 RPM.

For the sake of science, I drained that oil and did a 5 quart Valvoline 5W/30 and 1qt MMO treatment, PF-63, then the next day I added 1 can of Liqui-Moly Hydraulic lifter additive.

The oil I drained with 2500 miles, had no metal, no flakes, but a small layer of a velvety-dusty goop and maybe what the last few oil changes was breaking up. Not alot, but maybe a couple finger tip amounts.

I currently have about 100 miles on the cleaning concoction of oil, MMO, Liqui-Moly.

The symptoms seem to be improving slightly. The tick usually doesn't happen until about 20 sec after I start the engine when hot, but sometimes it will happen right away.

If I raise the idle, it tends to stop.

If I shut the engine off and restart, it sometimes takes about 10-15 sec to start up.

I drove home from work, about 30 miles today and it was quiet. I let the engine idle for 20 min and it was quiet. I ran an errand today after it cooled and it came back at idle.

Sometimes it will tick at half cam speed, and stay very consistent.

This is hit or miss, but I have some questions...

Could this possibly be the O-Ring restricting some volume and not pressure? Or does a bad O-ring only drop pressure?

My hot oil pressure reading on the sensor displayed in Torque is 21-23 PSI at a hot idle, oil temps at 200-210 deg,.this is also with a slightly thin oil/MMO mix.

It sounds like it's either cyl 4,6,or 8, hard to tell, but on the pass side.

Engine runs fine, smooth idle and smooth power.

Not an exhaust leak or loosen spark plug wire, it almost sounds like a spark but definitely a lifter....again, high-pitched, light tick.

I'll get some videos posted shortly.

In my opinion there is nothing wrong with that hot idle pressure - especially with thinner than normal oil in there. That's about where both of mine sit, too. The sound is likely a lifter that won't keep oil pressure consistently and thus can't maintain lash. There's a pintle valve in each one that can leak down if the spring isn't strong enough to keep it closed fully any more. In any case, my bet is that it's a mechanical problem with the lifter that continued treatments with various chemicals will not resolve. It's not a big deal to leave it as it is, in my view, but the fix will be new lifters. And when that time comes, you might as well do a mechanical AFM delete with new cam, etc.

 

[dkad260]

In any case, my bet is that it's a mechanical problem with the lifter that continued treatments with various chemicals will not resolve

This could be the case, naturally I still want to exhaust a few possibilities before I throw in the towel.

I'm removing the current oil/MMO today and will give Rislone a try with some fresh oil. After that, I will see if I can run some B12 down the pushrod of the trouble lifter.

What has me guessing is possibly the cleaning properties of the Redline may have allowed a small buildup in the tiny oil passage of the lifter. The fact I found a little bit of that fine, velvety dirt in the oil makes me think the 10K miles of Redline over the course of 2 intervals could have been aggressive enough with cleaning.

I'm not knocking Redline, I've used it for years and still will, but my motor could have had some gunk somewhere and not their fault...may not even be related.

This light tap if it were a mechanical problem, wouldn't it happen all the time?

I drove 30 miles home and could hear it halfway home at a red light when next to another vehicle.

When I got home, I shut it off and restarted after about 5 sec, and all was quiet for a good 5 min or more.

 

[B-train]

So is this not just a pan removal, pick-up tube removal, then O-Ring change? Does the front cover need to be removed?

You can do it with the pan removed, front cover stays on. Very simple once the pan is off.

But, I do agree with what @Geotrash stated. I don't see anything that looked abnormal to me. Mine shows very similar on the dash when warmed up. If it is some varnish buildup, then some MMO or ATF with a couple oil changes may cure it. If it's a mechanical wear issue, then you will need to replace hard parts.

The noise from your 1st video through the wheel well sounds similar to what my daughter's 3.8L did before some MMO. It takes some time for the varnish to dissolve. If it goes away after a short bit, then I'd say try and get some longer drives on it to really move the fluid around.

 

[Geotrash]

This light tap if it were a mechanical problem, wouldn't it happen all the time?

Not necessarily. The oiling of a lifter isn't a precisely metered process where exactly 3 ml of oil gets in there every time. Sometimes it might be 2 ml, sometimes it might be 5, depending on many factors, so if the pintle valve isn't sealing right it would lead to inconsistent taps accordingly. That's why I think it's a mechanical problem with the lifter. And again, I see no problem with driving it as it is. It's still just a light tap. You'll know when it's time to get that lifter out of there.

 

[Ibustbravo]

Hmm... This is a 'zen and the art of motorcycle maint' moment.. Do you let it go and replace the engine/parts when it tears up or do you fix it now?

If it wasn't such a clean truck, I'd let that sucker tick and smoke until it gave up it's ghost.

 

[L8T BURB]

This seems VERY similar to my experience before the lifter on cylinder 4 of my 186k mile 5.3 decided to leave the chat! Oddly enough, I also used MMO in an attempt to possibly clear anything that may be blocking proper oil passage. In my situation, the MMO seemed to actually speed up the lifter failure which led to the lifter in cylinder 4 completely collapsing. I would say you're on very borrowed time here, and regardless of repairing now or later, I believe a FULL DOD delete is in order.

 

[donjetman]

Somebody tell him about the italian tuneup

 

[dkad260]

if the pintle valve isn't sealing right it would lead to inconsistent taps accordingly. That's why I think it's a mechanical problem with the lifter.

Yeah, with all the lifters I've heard in my days, I don't like how this has that very light tick than a tap. I can rev it up all day long to make it quiet, but that lash is still there.

I'm not betting the farm on chemicals, but ATM it's better than pulling a head.

I really don't need this right now..lol. sigh.

 

[dkad260]

I believe a FULL DOD delete is in order

If this was a pre-2010.5 I would be all in, but there seems to be a revision after that and honestly the system works real good....that being said, I have my current issue, but I wasn't the original owner. If I was the inside would be almost spotless.

Fingers crossed on this one, next to worst case I will be pulling a head.

 

[L8T BURB]

If this was a pre-2010.5 I would be all in, but there seems to be a revision after that and honestly the system works real good....that being said, I have my current issue, but I wasn't the original owner. If I was the inside would be almost spotless.

Fingers crossed on this one, next to worst case I will be pulling a head.

Hopefully you come out good on this one. FYI, my failure was on a 2015 Suburban.

 

[dkad260]

Update on this....

I used a stethoscope and it seems the loudest tap is around cylinder #6, so I pulled the valve cover to start getting into this.

Valvetrain looks real good as far as cleanliness, nothing looked out of place.

I wiggled all the rockers after I rotated them off the heel of the cam, all had normal back and forth but some have a little up and down.

I pulled #6 intake and the pushrod bore looked clean and the lifter looked ok from a visual perspective.

I then pulled #6 exhaust and there was quite a bit of up and down movement in the trunion....probably at least .030".

The #6 exhaust lifter bore was clean and the top of the lifter looked good, sorry, the video when on top the lifter isn't as clear as my phone display, but nothing out of place and naturally this tells me nothing of what may be going on inside the lifter. I shot some B12 in there to soak just in case after the fact.

This is the up and down movement on the #6 exhaust trunion....this IME, should not be like this. The intake moves up and down a little, but not like this.

Luckily there's a dealer near me, open late and has one exhaust rocker on the shelf. I'm going to get it and see if this hopefully changes things.

@Geotrash yeah, definitely looking like a hard part issue.

 

[Geotrash]

Update on this....

I used a stethoscope and it seems the loudest tap is around cylinder #6, so I pulled the valve cover to start getting into this.

Valvetrain looks real good as far as cleanliness, nothing looked out of place.

View attachment 412738

I wiggled all the rockers after I rotated them off the heel of the cam, all had normal back and forth but some have a little up and down.

I pulled #6 intake and the pushrod bore looked clean and the lifter looked ok from a visual perspective.

I then pulled #6 exhaust and there was quite a bit of up and down movement in the trunion....probably at least .030".

The #6 exhaust lifter bore was clean and the top of the lifter looked good, sorry, the video when on top the lifter isn't as clear as my phone display, but nothing out of place and naturally this tells me nothing of what may be going on inside the lifter. I shot some B12 in there to soak just in case after the fact.

This is the up and down movement on the #6 exhaust trunion....this IME, should not be like this. The intake moves up and down a little, but not like this.

Luckily there's a dealer near me, open late and has one exhaust rocker on the shelf. I'm going to get it and see if this hopefully changes things.

@Geotrash yeah, definitely looking like a hard part issue.

Gooooood catch!! That valvetrain is the cleanest I’ve seen so it’s definitely been maintained. But I agree that trunnion has too much play and that would also explain the lifter lash noise.

 

[dkad260]

I have some good news and some not yet good news.

The not yet good news is I still have a very light tick.

The good news, I suppose, is the tick is on #8 and not an AFM cylinder...#6.

What I did was replace the sloppy #6 exhaust rocker and I checked cyl #4 and that seemed ok, not as bad as #6.

Before I replaced the valve cover, I pulled the #8 exhaust rocker and that one is worse than #6 exhaust. I still ended up replacing the #6 exhaust rocker since that was where the noise was concentrated using the stethoscope.

When I started the engine it took 5 min for the tick to start, but overall the valvetrain was slightly quieter and now the ticking noise is very pronounced on cyl #8. Since #6 is quiet now it's very easy to isolate the location.

I will likely replace all the rockers eventually, but the next step is to replace both rockers on #8 and probably the intake rocker on #6.

At least it appears I'm now dealing with a non-AFM cylinder so fingers crossed there's no compromised AFM lifters and another new rocker will fix this.

I was surprised to see the new rocker has a slight movement up and down in the trunion, but nothing like the old one. You would think there would be near zero movement up and down or radially.

 

[Dustin Jackson]

@dkad260 At that point I would have gone all the way in and done a proper inspection of the lifters and cams. LS engines have always been prone to lifter failures even before the AFM system was introduced so you could have a pitted lifter elsewhere but you wouldn't know unless you pulled the heads.

When I had a lifter failure there was a loud rattle at idle but once I tore into the motor everything looked perfect and wasn't able to find any damage until I actually got the lifters out.

 

[dkad260]

At that point I would have gone all the way in and done a proper inspection of the lifters and cams

I agree and I'm all for getting inside and seeing exactly what's going on. However we are talking about a vast difference in labor and downtime, and this is currently my daily driver.

I'm surprised the OE rockers have any up and down travel, but safe to assume it's designed that way for some reason.

I can see how problems could arise when that clearance opens up and I want to replace the other rockers on cyl 8 before I start pulling heads. Only took maybe 15 min to pull the valve cover so not a huge undertaking in the least.

The #6 exhaust rocker in the video has a good amount of radial play, but #8 had more. Rockers will be here this week and will at least get those changed out. For $12 each it's worth a try.