kojimep

I was not able to ever pin point where it was coming from. Even with a mechanic stethoscope the trick always sounding the same everywhere around the engine. But the common ones I had checked for were: *Any injectors louder than the others *High pressure fuel pump area *Approx location of each cylinder on the valve cover *fuel feed hose that goes into the high pressure fuel pump (supposedly a check valve in there that can get noisy?) *vaccum pump *exhaust manifolds and pipe going to the back of the truck I could hear the tick at every one of these locations, and none were ever any louder than another. That said, a few weeks it started misfiring continuously on cylinder 4 @ 102k miles, found a bent push rod, collapsed and spun lifter, wiped cam, and damaged block. Had to replace the engine. I don't know that the two are related at all, but after the lifter had collapsed I didn't seem to hear to that tick anymore. Definitely hope you don't have my poor luck with this though.

Update - It wiped out the cam lobe too, so now most likely have to have the engine replaced .

This is where I'm at as well. Just trying to get the lifter replaced for a decent cost, then I'll trade it on a 250/2500 and never have to worry about these stupid lifters again.

I recently had an afm lifter collapse at 102k and I'm considering doing the full delete with non-afm cams. Anyone have any info how on reliable the engine would be vs just replacing with stock afm lifters and tuning the afm off?

Good Idea, I'll give that a try thanks. The ticking matches engine rpm and goes up/down with it, and makes the sound both at idle in park, and while driving (though harder to hear over the wind noise). It is particularly noticeable with the window down in a drive through where theres a solid brick wall next to the vehicle to bounce sound off of. I've used a stethoscope to try and see if any of the lifters are louder than the others, I've checked the vacuum pump, the fuel pressure rail, the exhaust manifold bolts, and no location so far seems to sound worse than any other. I'm running out of ideas to check lol. Also, just noticed I put this in the wrong sub last night on mobile smh. Sorry.

Had a ticking/ clicking sound for quite a while. Used a stethoscope and it doesn't seem to be coming from anywhere on the engine. It only happens once the it has warmed up a while, sounds fine on cold start. Does this look like it could be an exhaust leak at the clamp just in front of the exhaust pipe?

Original Vacuum pump? Yes it is.

Getting one today and I'll check it out tonight after work. Would you hear a lifter tick through the valve cover, or would it have to be on the head directly? Also on the short list is the vacuum pump like JimCost2014 recommended.

I've got a 2015 6.2 with ~82k miles on it. Recently, about 2 weeks ago, I noticed the engine was making a much louder ticking sound than it used it, but I only notice it once the engine is warmed up (haven't heard it on a cold start yet). The noise does vary with rpm, but there does not seem to be any loss of power or mileage. Any recommendations of easy things to check or should I just bring it in to the dealer? We really only drive it on weekends, and I've put maybe 500 miles on it since I first noticed the tick. Thanks. Edit: I forgot to mention that the noise is much more noticeable from the passenger side of the engine bay, and that I cannot hear it at all inside the cab when driving, but the ticking is definitely considerably louder than the engine used to be.

I made an account just to come on here and post this. When I call to schedule an appointment for the brake vacuum pump recall in my '15 Sierra Denali (scheduled for tomorrow, 2/11/2020) the service guy said there's also an open recall on the rear defrost, even though I can't find anything else about it online for US vehicles. He said they need to check the resistance on the window first to see if the whole thing needs to be replaced or not. I live in MN (2nd owner) and the truck was originally sold here as well. I will say, nearly every time we are using the truck our 2 young kids are in the back (1 rear facing still) so it's a little concerning.