Now What?!?!

[swathdiver]

So frustrating! Just fired it up, no noise until I walked around to the front and then it started again.

Torqueing the rear upper control arm nuts is a real PITA by the way. Cannot get our torque wrench in there to get any movement whether on the ramps or with the wheel cranked all the way. Guess we'll have to pull the wheel again. Darnit!

 

[OR VietVet]

Aren't those arms supposed to be torqued with the weight of the vehicle on the ground? If you remove the wheel for access, I would still put the weight down on a stand to simulate. Unless I got it wrong and someone else chimes in.

 

[ls1frc]

Post a video of the noise.

 

[thompsoj22]

Your not "messing" with viscosity or brands of oil in anyway are you? even if the filter were dry everything should pump up within seconds without any brand changes in filter/oil vis. I dont have the afm system but it sounds like one lifter is jammed in the ramp area and needs to be freed up. Can you activate afm and allow the system to do its thing and possibly fix itself and then turn it off again? As you can tell i dont know shi! about afm, lol

 

[swathdiver]

Aren't those arms supposed to be torqued with the weight of the vehicle on the ground? If you remove the wheel for access, I would still put the weight down on a stand to simulate. Unless I got it wrong and someone else chimes in.

Funny that you say that. The shop manual mentions no such thing but everywhere else does. When we initially tightened the uppers and lowers, we positioned them as if the truck were sitting on its tires. When I do pull the wheels to tighten the rear nuts on the uppers, we're going to make sure that the arms are where they would be if the truck was sitting on the ground as before.

Post a video of the noise.

Your not "messing" with viscosity or brands of oil in anyway are you? even if the filter were dry everything should pump up within seconds without any brand changes in filter/oil vis. I dont have the afm system but it sounds like one lifter is jammed in the ramp area and needs to be freed up. Can you activate afm and allow the system to do its thing and possibly fix itself and then turn it off again? As you can tell i dont know shi! about afm, lol

Nope, same brand of oil and filter too. Good idea about AFM, thanks!

Sat one of my kids down yesterday to listen to some youtube videos of folks mentioning the same problem. She said it sounds like an exhaust leak to her and just like one of the videos. With all of my ailments, I'll trust her senses more than mine right now.

So after that I decided to take the truck out for a drive. My wife was suffering from a touch of cabin fever and joined me. I threw in all the straps and tow gear in case something happened in the back and off we went. About a quarter mile down the road we heard a clanging noise as the 22mm wrench my little one left on the upper control arm bolt fell away and onto the road. Turned around and picked it up and then got on it pretty good to get up to speed. The tires spun and traction control came on and the motor was running great.

Drove out to the Martin Road Scenic Highway and then back around towards town where we went off road to run in 4HI and 4LO for a few miles and got the truck covered in mud. After that we went to dinner. From inside the cab the sounds cannot be heard. Frankly, I think it is an exhaust leak now, there's no way the engine would run like that with a partially collapsed lifter and not throw codes or even a single misfire on the Tech-2. Could I be wrong?

 

[OR VietVet]

Can you get a stethoscope and really get in there at the exhaust manifold? I would take the probe out of the end of the stethoscope hose and just use the hose to listen. I have found many a vacuum leak doing it that way.

 

[91RS]

It could be a collapsed lifter with no misfire. Working on this 10 Escalade now which had no misfires at all and ran smooth as glass, just very noisy.

 

[iamdub]

AFM disabled since 2017. Noise happens faster as rpms go up. If it is a lifter Chris, why no CELs or misfires?

The lifter can be noisy enough to hear before it gets bad enough to cause a misfire. Does the noise ever go away? Does it increase with more rpm? Is it louder with higher rpm?

Been working late, but, what Ron said. On first start after sitting for a couple of weeks, I had one that would tick. It varied in loudness and lasted anywhere from three seconds to a few minutes. The engine ran fine and I never got any SES lights or felt or logged any misfires.

Also, your symptoms are reversed from the norm. Usually, the lifter is loud then quiets after oil gets circulated and pressure builds. After reading further, I see that you had not ruled out an exhaust leak. While they, as well, usually quiet down in time as the metal heats up and expands, it's certainly possible that it could expand and deform in such a way that it creates an exhaust leak.

 

[swathdiver]

Can you get a stethoscope and really get in there at the exhaust manifold? I would take the probe out of the end of the stethoscope hose and just use the hose to listen. I have found many a vacuum leak doing it that way.

Yes, all you hear is the whoosh of the exhaust air, no other sounds really.

It could be a collapsed lifter with no misfire. Working on this 10 Escalade now which had no misfires at all and ran smooth as glass, just very noisy.

Been working late, but, what Ron said. On first start after sitting for a couple of weeks, I had one that would tick. It varied in loudness and lasted anywhere from three seconds to a few minutes. The engine ran fine and I never got any SES lights or felt or logged any misfires.

Also, your symptoms are reversed from the norm. Usually, the lifter is loud then quiets after oil gets circulated and pressure builds. After reading further, I see that you had not ruled out an exhaust leak. While they, as well, usually quiet down in time as the metal heats up and expands, it's certainly possible that it could expand and deform in such a way that it creates an exhaust leak.

Well, I guess the collapsed lifter cannot be completely ruled out. In my experience, a ticking lifter does not necessarily mean a collapsed lifter.

Don't hear anything amiss when the listening probe touches the manifolds or heads or valve cover bolts. The noise resonates through the injectors and is loudest at #4. I did not get a chance to put the probe under the manifolds at the head, would like to do that or even a piece of paper to see if the exhaust blows on it.

Very sore today and it is gorgeous out, so have been fiddling in the garage enjoying the weather and trying to rest my eye balls.

 

[OR VietVet]

I would listen with a stethoscope from a complete cold start to a complete warm up and maybe have to do it a few times. Intermittent problems are a PITA!