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Posted

ok, the truck wont do this all the time it does it about 65% of the time in 4cyl mode, if it would do it all the time i would just take it to the dealer, on the driver side bank when in V4 mode under all conditions although loudest under max load in v4 before switching to v8 i have a ticking you can hear in the cab with the raido on at a low volume. the best way to describe it is how a truck sounds with a broken exhause manifold bolt. i checked, all the bolts are intact and tight, i threw a wrench on them. has anyone had the same issue? i dont want to wast time at the dealer for them to say they cant replicate the issue. when it is ticking and it switched to v8 if you are listening closely you can still hear it its just much quieter.

 

Note this is not injector noise, the truck has 13k on it it started around 11k

  • 4 months later...
Posted

I'll add that I hear the noise in the EXACT same place and it can be heard from the passenger side of the cabin.

 

Noise while giving it slight acceleration while staying in V4. Can occasionally be heard in V8 but most noticeable in V4.

 

This is NOT the same issue as the DI clicking at idle.

  • Like 1
Posted

Any chance it's from the exhaust system valve that reduces the drone when in V4?

Posted

ok, the truck wont do this all the time it does it about 65% of the time in 4cyl mode, if it would do it all the time i would just take it to the dealer, on the driver side bank when in V4 mode under all conditions although loudest under max load in v4 before switching to v8 i have a ticking you can hear in the cab with the raido on at a low volume. the best way to describe it is how a truck sounds with a broken exhause manifold bolt. i checked, all the bolts are intact and tight, i threw a wrench on them. has anyone had the same issue? i dont want to wast time at the dealer for them to say they cant replicate the issue. when it is ticking and it switched to v8 if you are listening closely you can still hear it its just much quieter.

 

Note this is not injector noise, the truck has 13k on it it started around 11k

It could be pre-detonation. Maybe anti-knock sensor id defective. See if a higher octane fuel fixes it.

Posted (edited)

My truck does the exact same thing. I'd describe it as more of a chugging sound than ticking, but otherwise you've described it exactly. I tried higher octane fuel and it doesn't change anything. I just recently noticed that it seems to only happen in V4 mode so I may just buy a hypertech and turn off AFM.

 

EDIT: Also my truck did not start making this distinctive noise until 10-15k miles so there's no way it's supposed to do that.

Edited by 14x4
Posted

Had the truck in for the V4 to V8 chirp. They fixed it with the updated exhaust system and told me it also fixed the ticking.

 

Absolutely didn't change a thing (my wife claims it's worse) so I'll be giving the dealer a call tomorrow.

  • 5 weeks later...
  • 3 weeks later...
Posted

Anyone have anything new on this? Mine was awful this weekend but it has made me realize it will do it all the time if its over 85 deg out. Sadly my dealer is not open on weekends

Posted

Ok.. putting some trouble shooting logic to this this morning (i am a mechanical engineer and worked as a technician all through college). Not sure about others but when mine is in ticking mode it def feels a bit doggy compared to normal. There is no doubt in my mind its an exhaust tick, i have had a gmt800 and 900 with broken exhaust mani bolts, i know that sound like the back of my hand! So with that said if you take the two issues, loss of power and the ticking, i see signs pointing to an exhaust restriction. I think that the exhaust flapper is sticking closed or partially closed (i have no idea how sealed the closed position is) . At this point i think i am going to wire the valve open and see if it eliminates the issue, i have a strong feeling it will.

  • Like 1
  • 2 weeks later...
Posted

Had my truck into the dealer today for it's 3rd ride along as the service techs are having trouble hearing the ticking. It's very distinct to my family but perhaps we're tuned into it.

 

I had a recording of the noise and they suggested it could be a sticking lifter. They called GM and they have had this issue before on these trucks and have recommended replacing the lifters. Good news is they think they have a fix, bad news is it seems to be a complicated surgery.

 

I'll be in touch in a few weeks when it's all said and done.

Posted

I'm anxious to hear your results on holding the flapper valve open. I've been wanting to remove mine completely but may just bolt it open for now to save time/money taking it into a shop.

  • Like 1

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