05 and 06 KJ CRDs all had 7v ceramic glow plugs and what PN they were doesn't really matter as they are no longer in stock anywhere although with a lot of digging you might find some new or used but I would not recommend using them. When the ceramic glow plugs die, which I presume is more related to duty cycles (more cycles in colder climates) than mileage they tend to shed bits of the tips which can either pass out of the engine with no damage or take out valves/piston walls/turbo if you are unlucky. Frankly I replaced mine and stoutdogs as preventive maintenance.
Replacement options via IdParts, probably best source:
1. OEM 5v steel (4 glow plugs + controller + an ECU flash to change voltage supplied to the plugs which GDE can do or a dealer but it must be done before the new glow plugs are electrically connected = total parts cost including flash ca. $250 US) - downside is I've seen some reports of harder starting in very cold climates.
2. Etecno1 7v steel GX3123 (4 glow plugs drop in no controller change or ECU flash = total parts cost ca. $100) - downside is there appears to have been a production issue on some recent Etecno1 plugs resulting in early failure but as far as I know the bad ones have been replaced for no cost.
Replacing them is not technically challenging but:
1. do your self a favor and get Weeks101 (
viewtopic.php?f=5&t=78238) intake elbow kit which gets a lot of useless junk off the engine and makes glow plug replacement a snap.
2. if you don't do #1 you MUST and as geordi and I know REALLY MUST pull the intake elbow fully off the engine when removing glow plug #3 and I'd recommend at least getting studs and nuts to reattach the intake elbow as access to the back bolts is a $^^$%(
other than that a slightly warm engine (block heater warm) helps loosen things up; proper size socket wrench and extension should make removal a breeze; be careful not to bang the ceramic tip on the way out (it's not easy to break but it is possible); if one of the tips is broken when it comes out do a comparison break on another tip (the new break will be nice and clean and if you are lucky the old break will be comparatively "dusty" indicating an old break and that the broken piece exited your engine with no harm). On reinstall some have reported that a bit of fuel line makes a handy "handle" to get the new glow plug started in each hole and a smige of anti-sieze might also be in order.