Have an 05 Stratus SXT 2.4L DOHC. Getting a weird sound from the drive belt side of the motor. It's intermittent and only seems to do it during idle. Sounds like a bearing or something trying to engage. No squealing though. Sounds more like marbles racing around. Sometimes it's a quick chunk and others it will continue to race for a bit before stopping. Doesn't matter if A/C is on or off. New drive belt, tensioner and alternator (sound began before they were installed). Only other thing is a noticeable vibration in the vehicle just as this started happening (you can feel it in the gas pedal and hear it in the dash). Performance seems unaltered however I am noticing the trans downshift while decelerating (not hard or anything - just when it reaches certain rpms you can see tach go up and feel it happening). Not sure if it always has and I'm just noticing it now because of the extra vibration or if it's a symptom. Any ideas???

 

Take the belt off and with the engine off, play with each individual pulley to see if you can pinpoint anything, twist and torque on the pulleys to see if they have any wobble, spin them slightly back and forth to see if you feel any play before they spin internally, pull them straight in and out to see if they have movement, then give them a good hard spin in both directions to see if you hear any grinding or anything. The old school trick doesn't seem to work anymore in my experience...which was spraying wd40 onto a pulley and see if it stops, then the next pulley, etc...problem is, no matter where you spray, enough will get carried to the bad point and lube it up enough to make it stop. So that old trick is a waste of time these days.