My 2007 Chevy Tahoe LT

[Charles Bradley]

My truck has some sort of clicking noise but it only happens when I am on the freeway going over 60 miles an hour. It does not happen right away but once on the freeway for awhile I will hear a clicking sound that will get louder as I drive at that speed once I get off the freeway and come to a stop it sound like the truck is not running off all the cylinders almost like a wire is unplugged or something but all of a sudden it will go away as long as I’m not on the freeway driving over 50 miles per hour. No engine lights, no change in oil pressure just the noise. Several mechanics have looked at it but cannot pinpoint what it is or why it’s doing it! It’s been doing this since December of 2020! Some mechanics keep asking me did someone die in the truck maybe it’s possessed! Not funny but not sure how to proceed!

 

[Sam Harris]

It could be a lifter that’s not active, presuming you have AFM on the truck. Lots of issues with the AFM / DOD on these engines. Maybe try keeping it out of AFM by manually shifting it into 5th gear, and test, to determine if you still get the noise or not..?

 

[Charles Bradley]

Some did tell me when the truck reaches a certain speed it shuts it down to 4 cylinders. I believe that is when the noise occurs. This year engine seems to be problematic. How do you manually put it in 5th gear?

 

[iamdub]

Some did tell me when the truck reaches a certain speed it shuts it down to 4 cylinders. I believe that is when the noise occurs. This year engine seems to be problematic. How do you manually put it in 5th gear?

I was confused why y'all were mentioning AFM as this was posted in the '00-'06 section and that generation didn't have AFM. But I see you have an '07.

Your '07 doesn't have a 5th gear, it has the 4-speed 4L60E.

What you can do is press the top button of the DIC controls (the "road going into the mountains" button) until you get to the screen that displays:




Watch the "V4/V8 MODE" part to see if the clicking correlates to the AFM mode.

 

[Sam Harris]

Some did tell me when the truck reaches a certain speed it shuts it down to 4 cylinders. I believe that is when the noise occurs. This year engine seems to be problematic. How do you manually put it in 5th gear?

Sorry I didn’t have that right for your rig. It does sound like it’s got something to do with the AFM though, so however you can deactivate that would definitely be a good thing. (I believe there are a few OBD dongles for your year, to accomplish this) hopefully there isn’t too much damage but if it’s tied to the V4 mode / AFM, it sounds likely a lifter and you’re probably going to need to pull a valve cover to find it. Not sure if any of the mechanics you’ve visited have popped those open to have a look, or mentioned this as a possibility.

 

[Sam Harris]

Some did tell me when the truck reaches a certain speed it shuts it down to 4 cylinders. I believe that is when the noise occurs. This year engine seems to be problematic. How do you manually put it in 5th gear?

Double tap..