I have been hearing this sound for some time now and I can't make out what it might be.
Figured I would post up a YouTube video to see if you guys can compare it to your own CRD's, it is hard to make out over the normal engine clatter but if you replay it a few time and listen to the back round you can hear the roar sound. Roar is the best way to describe it, I am going to run the jeep without the belt on to see if it is audible...

My best guess is with the original fan clutch, at 145k miles its bad and noisy.

http://youtu.be/tw4AWfiuTnc

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-05 Dark Khaki Limited CRD. GDE ECO tune. In-tank lift pump, Transgo doo doo kit, B&M trans cooler, replaced trans solenoid pack and filters, Newer Michelin tires, Timing belt with all related parts replaced at 110,000miles.

I think I noticed a little something, but I'm not sure. Can you repeat including raising and lowering RPM?

DOC

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2005 KJ CRD Ltd Detroit TrueTrac Bilsteins G2 GDE "HOT" ECU GDE TCM "Tow Tune" "euro" TC SEGR Weeks Elbow New HG at 130K ARPs Clean CAT aFe Filter Magnaflow Exhaust EHM Cumminos In-Tank Lift Pump Hayden Fan Clutch Nylon Fan VH Enabled with GDE lower shutoff point Recalibrated Temp Gauge Tekonsha Prodigy Sears P-1 ZDDP

What I hear sounds a lot like belt "howl". At idle look down the belt to the idler; if the idler is bouncing (e.g. not barely twitching) the alternator clutch pulley is bad get lifetime warranty alternator from like AutoZone. If that's not it pull the serp belt and see if sound goes away. If it does start looking at everything that rolls with that belt (2 idlers, viscous pulley, tensioner idler, etc.)

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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

Good call, I will try to find some time this weekend to pull the belt off. I don't have any tensioner bounce and the alternator was replaced last year with a pricey ($300) OEM unit so that should be good.

Has anyont noticed the fan clutch making noise when worn?

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-05 Dark Khaki Limited CRD. GDE ECO tune. In-tank lift pump, Transgo doo doo kit, B&M trans cooler, replaced trans solenoid pack and filters, Newer Michelin tires, Timing belt with all related parts replaced at 110,000miles.

My fan clutch was shot, and didn't make a peep.

You can see what a blown fan clutch looks like if you check out sir sam's youtube videos, "CORobotchicken" IIRC.

Sounds like a bearing/tensioner failing to me.

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Silver 2006 KJ 2.8L CRD Limited:
GDE ECO Tune / Fumoto Valve / E-Tecno GX3123 7v Glow Plugs / 2nd Gen Fuel Head / Mishimoto RED Hoses / Rockers/Lifters @ 114k / Hayden FC + 11 Blade Nylon / Sears P1 Battery / Transgo 45RFE-HD2 Reprogramming Kit / Timken Front Bearings

Ok good to know the fan clutch won't make any noise, I am sure mine is toast. time to check idlers and such.

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-05 Dark Khaki Limited CRD. GDE ECO tune. In-tank lift pump, Transgo doo doo kit, B&M trans cooler, replaced trans solenoid pack and filters, Newer Michelin tires, Timing belt with all related parts replaced at 110,000miles.

It sounds like a bearing is worn for me. Could be the alternator, or a pulley. Get a screwdriver and put it in the top of the alternator, grab the screwdriver with the palm.of your hand and make a "funnel" like shape and place your ear into your palm and see if you can hear the sound amplified... if you can't, could be a pulley bearing from serpentine belt or timing belt. I couldn't tell which without opening and inspecting.

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2005 kj CRD, samco, suncoast tc, provent, Kennedy lift pump, GDE ECO full torque, 2nd gen filter head, 245/70/16 a/t tires, mopar light bar, fumoto oil valve, OEM Skid Plates, ARB Front bumper and HD OME, tru cool LPD47391 40k GVW tranny cooler (stock cooler delete), FF Dynamics e-fan and shroud, rocker arms replaced, HDS2 190F thermostat.

P.S. if your fan clutch is bad, you should see it by spinning the fan with your hands, I think fsm sais than.more than 8 rotations means a bad clutch, I'd say more than 1 rotation is shot...

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2005 kj CRD, samco, suncoast tc, provent, Kennedy lift pump, GDE ECO full torque, 2nd gen filter head, 245/70/16 a/t tires, mopar light bar, fumoto oil valve, OEM Skid Plates, ARB Front bumper and HD OME, tru cool LPD47391 40k GVW tranny cooler (stock cooler delete), FF Dynamics e-fan and shroud, rocker arms replaced, HDS2 190F thermostat.

Well I get a little paranoid with the dang jeep, anyone else hear a noise like this?
It's obviously coming from the timing belt area.

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-05 Dark Khaki Limited CRD. GDE ECO tune. In-tank lift pump, Transgo doo doo kit, B&M trans cooler, replaced trans solenoid pack and filters, Newer Michelin tires, Timing belt with all related parts replaced at 110,000miles.

When my fan clutch started squeaking, here's how I found it out. Open the hood with the engine idling and reach in through the open driver's window to kill the ignition. Listen as the engine stops. On mine it would come to a quick stop and then the fan would make one more revolution while going squeeeeeeeeeak! Just couldn't pinpoint it with the engine running.

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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.

x2

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05 CRD Sport Dark Kahki

RRO: Adventure Rack/Rails ** MOPAR: Skids/Renny Flares & 255/75r17 (32.1) BFG M/T on JK wheels ** ARB: Bumper/IPF lights/790/948/shocks ** GDE: TCM/Hot Tune ** ROCKLIZARD: Super Sliders/Komodo Bumper

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