kojimep

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.

umm, not that Amsoil isn't good, but I have never seen a vehicle with an oil flow meter? The gauge is oil pressure, which is determined by the resistance to flow. If changing to the Amsoil oil/filter shows higher pressure on the gauge that means it is more difficult to flow (more likely higher filtration/restriction in the filter itself), though it could also be higher from the old/previous oil thinning over time.

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.