At idle, the engine purrs like a kitten but I do hear a distinct "chatter" kind of a sound. Sounds kinda metallic, chirping chatter, like if you ever have spun a unloaded pulley that has a bad bearing. It is persistent generally, but occasionally comes and goes. Smooths out and sounds fine at anything above idle. Any thoughts? Has 160k trouble free miles! Thanks

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05 Silver KJ Limited CRD born July 11, 2005
'88 Suzuki Samurai 4x4
'99 1/2 Powerstroke 4 door Dually 4x4
Kubota B7200 Diesel 4x4
Polaris 700 and 500 H.O. 4x4

I assume you changed your timing belt at the proper 100k miles interval? As to the noise you might take a look at your alternator pulley; at idle is the serp belt tensioner noticeably bouncing. If so that pulley is gone. It can be replaced but it may be easier to get lifetime warranty alternator from like Autozone.

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Sold to LOST member my 05 Ltd, GDE Stg II turbo + TCM tune, SunCoast TC w. Transgo kit, Steiger window regulators, Samcos, Fumoto valve, 2nd gen filter head with Lub. Spec. bleeder, Hayden clutch & 11 blade fan, inverted spare, P-1 battery, BF Goodrich Long Trail TAs, Etecno1 glow plugs, timing belt at 50K miles/8 yrs

Yes sir, did the timing belt. I will check the alternator pulley Thanks!

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05 Silver KJ Limited CRD born July 11, 2005
'88 Suzuki Samurai 4x4
'99 1/2 Powerstroke 4 door Dually 4x4
Kubota B7200 Diesel 4x4
Polaris 700 and 500 H.O. 4x4

This may sound completely obvious, but I had a similar sound the other day when I was on a road trip. I just got the Jeep back from having the timing belt done and they replaced all the pulleys. Naturally my mind drifted to it being one of these parts failing, as it sounded very similar. Then I noticed that my transmission fluid dipstick was about 1/2 inch not seated properly. I pushed it all the way down and sound resolved. I felt a little dumb.

Thanks for the reply but I had wired the transmission dipstick in the seated position long ago! Still haven't figured out what the sound is though. Thanks!

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05 Silver KJ Limited CRD born July 11, 2005
'88 Suzuki Samurai 4x4
'99 1/2 Powerstroke 4 door Dually 4x4
Kubota B7200 Diesel 4x4
Polaris 700 and 500 H.O. 4x4

Your description sounds exactly like a bad alternator pulley. Sometimes people take off the belt and spin the pulley and think it's fine, not realizing that inside the pulley should be a one-way clutch that allows the belt to turn the shaft one way (CW), but not the other. If your pulley is locked in both directions, it's bad.

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05CRD: GDE Hot ECU & TCM tunes, Provent, Cat filter, Facet lift pump, TransGo kit, Florida TC, Samcos, stainless brake lines, HDS thermostat, Renegade light bar,
Bilstein adjustables, Al's Gen 4.5 Arms, 235/85-16 Duratracs, DTT rear, Elocker front, EVIC+TPMS, Turbo timer, McNally pillar gauges, Weeks Stage II kit.