2009 5.3 engine sqeaking

[rat454]

This past week my sierra started squeaking. It's a cyclical squeak/chirp that changes with engine speed. The day it started by the time i finally got home to check on it the chirp was really loud where i had to turn the radio up with the windows up to not hear it. I took the main drive belt off thinking it was the idler or tensioner pulley but the sound is still there. I plan to take the a/c belt off next but the sound doesn't change when the compressor engages and disengages so I'm afraid it's internal. I rolled underneath the truck but couldn't pinpoint the source. Oil pressure is fine and i change it with mobil 1 every 4k miles. The dealership did repair an oil leak about 20k miles ago where they had to replace the oil pan gasket. other than that no other work has ever been done to it. Since i have another vehicle I parked the sierra and haven't driven it until I can better access whats going on. But I have cranked it a couple of times and let it idle to see if the sound is still there. One time i could barely hear the squeak when i first cranked it then the sound went away after about 30 seconds of it running. The last time i cranked it the sound was immediately there and increased and decreased in sound level for about 20 seconds then quietened down. I read in web searches that it could be valvetrain related.

The truck has just less than 70K miles on it so it should be covered by the 100K powertrain warranty. However I have a set of long tube headers on it and a BB tune. So before I put it back to stock to take it to the dealership I was wanting to see if anyone has had a similar experience. Maybe its something simple.

 

[Jsdirt]

70K yes ... but your getting close to the 5 year mark. Get it done NOW - don't wait.

 

Usually squawks and chirps are belt/tensioner/bearing related ... but if it still does it with the belt removed ... Hmmm ... Head gasket leak???

[6Sixathome]

It's probably the water pump. The two times that my engine was squeaking it was the water pump.

[rat454]

Its not the waterpump, alternator, powersteering or either of the pulleys. The chirp/squeek was still there and just as loud when i cranked it with the belt off.

[05Jay1500]

I'd be very surprised if the chirp/squeak you describe is valvetrain related, or anything else internal. I'd go ahead and remove the a/c belt and see what happens. My guess is that it's the a/c belt, or maybe the a/c tensioner since the sound doesn't change with the compressor engaged. Hope this helps.

[rat454]

I'm checking it tonight. Thanks for the reply.

[rat454]

My truck doesn't have a tensioner on the a/c belt. Only had time to open the hood and confirm this last night. Will try to take belt off or just cut it and see if the chirp is still there or not.

[Badass69]

Yeah your truck has an a/c tensioner on it... get down there and look. You can't pull the compressor over to pull the belt off. Its difficult to see even as open as trucks with e fans are. Remove that belt and see if it remains.

 

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[Gone Again]

Your AC belt is a stretch belt. No tensioner. You will need a special tool to remove or install.

[Badass69]

Jesus gm is dumb... yes correct no a/c tensioner.... another reason to never buy a gmt900 lol

 

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[rat454]

I removed the a/c belt by cutting it off and kept the main belt on. No squeak for the first 15 minutes of idling. The squeak started out as a faint squeak, squeak, squeak... then got louder and louder. I rolled underneath the truck and the sound seems to come from the trans bell housing area. Taking it to the dealer tomorrow.

[05Jay1500]

Interesting. Let us know what they find.

[rat454]

Just talked to the service manager and he said they are pretty sure its the camshaft causing the noise. He told me he was going to get the estimate ready and call me back. I quickly reminded him that it should still be under warranty since it only had less than 70K miles and was an 09 model. He checked and replied that it was under warranty and would start the repair process immediately. He's even gonna give me a loaner car to drive while its being fixed. Ill try to get pictures of the actual damaged parts and reply with what they believe caused it.

[05Jay1500]

In my first post, I said I'd be very surprised if it was valvetrain related. Wow - It seems your web searches yielded some good information. I would never expect to hear chirps/squeaks from engine internals that are usually so well lubricated. Hope the repairs go well.

[rat454]

Dealership said they had to replace the camshaft and lifters. They said a lifter went bad. Haven't see it yet but going to pick it up this afternoon. Will get pictures of the bad parts and post them and relay what the technician thinks caused it.