Engine has loud clack sound at idle

[JGau]

Have 2001 Ram 2500 that has recently changed sounds. There is a clacking sound at idle which sounds like one cylinder is not hitting the same as the others. If it where a gas motor you would think that it had a bad wrist pin on a piston. The truck runs fine and is normal except for the clack sound. The sound is not noticable at highway speed but very prominent at idle.

Took the truck to both Dodge dealer and Cummins dealer and they say nothing is wrong. The engine has 32000 miles on it and has had Delo every 4000 miles with stratospore filters for oil and fuel.

I have noticed that it seems no two Cummins engines sound the same. There are seven Cummins powered trucks where I work and they all have a different sound. None are as loud as mine. With the 100,000 mile warranty I know if something lets go it is covered, but I hate to screw something up if it is preventable.

Anybody else experience this same situation?

 

[Fireman Dave]

Not sure if this is the same thing, but both johnrv4 and I get a thumping noise from time to time. It's a hard noise to pinpoint. It seems to be most prominent during and after towing. For us it's more of a dull thud - sometimes a little tick - like a lifter in a gasser. One theory is timing changes while under load, but we don't know. They run like a clock, so we aren't worrying about it. John's is an ETH, mine is an ETC - both are 2001s.

 

[MidwestMotorman]

check exhaust manifold

You might want to look and see if you lost an exhaust manifold bolt or that the exhaust manifold cracked. The manifolds (both intake and exhaust) have been reported to loose bolts, and the exhaust manifold has definitely been known to crack.

 

[JGau]

Re: check exhaust manifold

Originally posted by nathanbush

You might want to look and see if you lost an exhaust manifold bolt or that the exhaust manifold cracked. The manifolds (both intake and exhaust) have been reported to loose bolts, and the exhaust manifold has definitely been known to crack.

Checked all bolts and they are tight. May not be anything, but after 15 months of driving the noise is new but the truck runs great except for the new noise.