I have a 2008 1500 Silvy with 53,000 miles and the engine is making a clunking/squealing noise. I know what your thinking belt or pulleys. I replaced the drive serpentine ...

I have a 2008 1500 Silvy with 53,000 miles and the engine is making a clunking/squealing noise. I know what your thinking belt or pulleys. I replaced the drive serpentine belt along with the idler pulley. But that didn't solve the problem, so I took both the A/C and drive belts off and started the truck and it is still making this noise. So now I'm stumped, I took the wife's stethoscope to see if I can pin point the noise, to me it gets louder in the bottom end, I tried each head but couldn't get anywhere near the firewall since the truck is lifted. The sound does quiet down after the engine has warmed up but you can still hear it if you are listening for it. I bought and extended warranty with the truck that covers pretty much everything that isn't normal wear and tear. But before taking it in I wanted to get some thoughts on what you guys might think it is and to see if ya'll think the warranty will even cover it or if it's just a simple fix (which I highly doubt). Here is a link to the video of the engine noise http://youtu.be/MRZ8asi3YVU This video is taken from the driver side wheel well.

It does sound like a bottem end noise. I have seen cracked flexplates make a noise similar to that. When they crack it almost sounds like a rod knock.

It goes to my local mechanic tomorrow and if he thinks the stealership will fix it under warranty or my extended warranty I'll take it to GM. I'll post whatever the problem is.

If you have warranty why not start with a dealer?

because if they dont cover it under warranty I have to pay for a $85 diagnostic fee, my mechanic is $30 and is going to tell me everything that needs to be fixed and what he recommends be fixed.

The only other noise I could think of would be if the exhaust started rubbing up against anything around the y-pipe. Easy enough to check - if its not that, it sounds like a trip to the dealer is the best bet.

I checked the exhaust it's coming from the bottom end of the engine or the bellhousing.

What did you find out?

They had to keep it overnight, they agreed it is not a normal noise but they want to hear it first thing in the morning when the engine is cold. So I should know tomorrow some time what's making that sound.

So, did they give you something to drive in the meantime?