EricArrow

Just bought a 04.5 HO with 233k on the clock and it seems to have a slight knocking noise while driving...ofcourse since this is my first diesel it may be normal but I figured I would ask anyway. The injectors were changed last year according to the previous owner and i just changed the fuel filter yesterday. It has good oil pressure according to the factory guage and seems to drive well.

Should I try an injector cleaner?...this truck was not worked hard so with my limited knowledge I figured maybe the motor has some carbon build-up. If so...what brand injector cleaner and how much do you guys recommend?

Thanks in advance..

oh...this is what it will be towing next summer..

Adaminak

Depends on the knock. All diesels knock on injection as it's the sound of the fuel detonating...where it gets flaky is if the knock is different than normal, and you won't know that if this is your first diesel truck. Easiest thing to do for a start is try to find another 04.5-07 and listen to it run. While you're listening to his truck, the other truck's owner can likely tell you in a few seconds if yours is running normal or not.

The factory oil pressure gauge is fake, and is not displaying what the engine is actually producing. If it falls below a certain threshold (think it's 5psi for 30 seconds?) then it'll drop to zero and the warning light will come on.

As far as clearing carbon, nothing works better than hard work. Hook to your trailer with modest load (your other vehicle maybe?) and drive up the longest, steepest route you can find. A lot of elevation gain is what you're looking for, not just a few steep hills, and keep the truck working hard. If you don't go over GCWR you shouldn't have to worry about EGT, and a single car isn't nearly enough weight to break anything. A treatment of Power Services, Howe's Meaner Cleaner, or Redline's Diesel Catalyst or RL-2/RL-3 can't hurt, but the hard work is what will really do the job right.