Strange Sound With Acceleration?

jtstacy77 · September 4, 2011

I have searched the forums and can't seem to find anyone with this problem, so here I go. My 06 avalanche 4x4 makes a ticki ng sound when the rpm's go above 2500 rpm. It is not noticeable at slow or cruising speed just when i get in the gas. It also does it if I am in a lower gear going downhill and the engine starts to rev a little. It sounds like a tick or knock, to me it seems to be coming from the engine compartment but it is hard to tell. I had it checked at local dealership but they said they couldn't replicate the sound. I have a month left on my powertrain warranty and would like to get it fixed before the warranty is gone. Any help is greatly appreciated!

jtstacy77 · September 5, 2011

Today I got in the avalanche and the engine makes a slight tick kinda like a slow sewing machine when idling. The loud tick starts at around 2200 rpm and disappears around 2500 rpm. Any thoughts?

possin08 · September 23, 2011

I would check the exhaust manifolds on the block, could be a small leak. I know a lot of the newer trucks Chevy and ford have had problems with snapping the bolts that hold the exhaust manifolds on due to the exhaust systems are not designed with enough flex in them. Typically you would hear the leak all the time, but it may be small enough that it only does it under certain conditions or rpms like you have stated. Just a thought..good luck

Hambone! · September 23, 2011

Any chance you could include a sound bite? There are just too many possibilities. Could be the snap of a spark, or the tick of a lifter, or the pop of an exhaust leak, the rattle of a piston....

jtstacy77 · September 27, 2011

Just updating post. Apparently I have multiple lifters that have failed and the camshaft is wore out. The truck is still in the shop and parts are ordered. I didn't get to talk to the service manager, but the guy I talked to said they ordered a new camshaft and all new lifters. I hope they can get it all back together and functioning properly!

Hambone! · September 27, 2011

They have any idea how it happened? At least its getting fixed though.

jtstacy77 · September 28, 2011

They have any idea how it happened? At least its getting fixed though.

I will talk to the service manager tomorrow and hopefully find out what caused the problem!

BlackZ71Silverado · September 28, 2011

They have any idea how it happened? At least its getting fixed though.

I will talk to the service manager tomorrow and hopefully find out what caused the problem!

Did you run it low on oil all the time?

jtstacy77 · September 29, 2011

They have any idea how it happened? At least its getting fixed though.

I will talk to the service manager tomorrow and hopefully find out what caused the problem!

Did you run it low on oil all the time?

I traded for it and it ha 80,000 miles on it. It didn't develop the sound until I I got to 82,000 miles. Changed the oil at 83,500 and it was still at the top of the crosshatch. I asked the service manager why it failed and he said the lifters were probably built with bad metal. This is the 4th truck that he knows of that has had similiar problems. Cam and lifters to go in tomorrow.