it is a 1998 dodge RAM with the 360 engine. auto trans. 110k miles makes a noise from engine area like a grinding noise. reminds me of bad berrings. but noise stops as soon as i let off. only happens under acceleraton like getting on the highway. any ideas of what it could be? thanks

 

does it sound like marbles in the engine.
if so, its pinging, caused by your leaking plenum.
welcome to df.

 

Does it do it in park or only in drive, if it does it in park i would say goto autozone and get a automotive stethoscope and listen to each pulley on the engine help ya narrow down the noise.

 

it only does it in drive. and yeah i guess you could say it sounds like marbles in the engine.

 

That's probably Ping. (spark knock) Have a look down your throttle body, and see if you see any oil there. Do you have an oil consumption problem?

 

Sorry to hijack, but I'm having a very similar problem and just want to figure out if I'm in the same boat... 1996 1500 with the 5.9. marble noise, almost sounds like a vibrating heat shield but more nasally. Most noticeable when at idle, and mostly drowned out by the engine when going down the highway. Disappears when in park or neutral. No noticeable oil loss.

I first thought it was a bearing going out (like in water pump, etc.), but then it would happen regardless of the tranny being in park or drive.

I'm familiar with the sound of ping/spark knock at it relates to poorly timed engines and or cheap gas (on other cars), and to me this is more regular sounding than that...

 

Yes it does have an oil consumption problem too. every time i stop for gas (being a 360 i get gas quite often) it seems like i am adding oil to it.

 

The marbles sound at low rpm sounds like a rattlin cat. Loose material in catalytic converter vibrating, most noticeable at low rpm's. Would be my guess, but I could be wrong. Oil consumption too would indicate leaking plenum. Could be both. Take a close listen to cat conv, take it to an exhaust shop or two and they'll probably verify or refute if the cat is rattling. And search "plenum tsb" on net, will give info on how to check for plenum gasket leak. Good luck, brotha. Let us know how it turns out.