I have a 2001 2500HD 6.0 4X4. it has 180,000 miles on it. i was driving today and as i started up a slight incline i started to hear this chatter from the engine area. i had great oil pressure about 60. it never drops below 40 even when warm at ideal. i also got it when i get the RPM's above 3000. it gets better and worse with the throttle increase and decrease. and goes away when below 3000 RPM's. any idea's what to check before i go all out an tear the whole bottom of my engine apart.

thank Jeremy

 

try having someone lay under the truck while u rev it up. they should be able to hear if its coming from the lowerend or not. if its just a chatter and not a knock it could be lifters or possibly the flywheel.

 

Are you sure it's coming from the engine compartment? Under different loads, I've noticed the computer system in these trucks makes a loud clicking noise like a IBM clone hard drive that's running hot.

Two things you could try:

The screwdriver trick-if you take a long screwdriver, and hold the blade to the different parts of the engine, and the handle to your ear, you can use it as budget stethoscope.

Also try accelerations from 20-60 on a highway or clean asphalt road with no traffic with your window down. Pull off your skid plates, and if it's the bottom end, you may be able to hear the chatter reflected back from the road.

I have to agree about localizing the noise, the chatter could also be the engine bogging under hard acceleration and pre-igniting a little.

I'm guessing by the mileage and the drivetrain that you have 410s, and you drive on the highway a lot . The high revs on the highway were the reason I switched to 342s in my 2500HD, I was worried what sustained running at 3200RPM + would do to the engine.

You'll be pissed if you rip the engine apart and it turns out to be something else. You might actually be better off running it till it breaks. Then you won't be guessing what the problem is.

OMG-Have you seen SUPERTEXAN's post? Same year, mileage, problem...

 

it only does it when in gear and moving. I think i may be a torque converter or the shift moduel in the transmission. But not sure. Friend told me to take it when the noise happens take it out of overdrive and see if it continues. if not its a torque converter is it does it a moduel.

 

make sure that the a/c belt and tensioner are good these trucks have a belt just for the a/c compressior that are prone to making a chatter when the tensioner spring gets weak. even see them fall off or break in two

 

was the fly wheel