Motorama

The motor on my 05 has a loud knock/tap at the top of the motor. It still runs fine and pulls fine. it sounds like just one rocker or valve
Could something need adjusting or is it likely something is broke. Anyone else had this. Motor only has 26k on it.
it's hard to get these worked on in the UK so if there's something i can find out myself first it will help.

MikeyB

Could be carbon buildup on the injector tips. Try running a heavy dose of diesel fuel additive and run the truck hard. Preferably towing something.

MikeyB

Spooler

You need to work it hard once a month towing something. Putting around can and will carbon up your injectors. Mine did it also until I learned to work it, it likes it.

Motorama

Thanks for the response. You mean like an injector cleaner or similar?

MikeyB

Yes, injector cleaner designed for diesel injectors.

MikeyB

Boris-MC1

I have the infamous knock also, try searching "engine knock" and a few threads will come up.

Lot of theories, no definitive answer.

I know that after I pull my 5th wheel for a few hundred miles, my engine seems to really quiet down and run smooth.

Boris

ptextreme

I too have a loud engine knock above 1200rpms, the dealer just replaced all the injectors last week, and the truck runs much better, but the knock is very loud above 1200 rpms, almost sounds like a wrist pin or a piston skirt on a gas motor. the engine has 79000 on it and is an 2005 stick. anybody else having this issue?

Motorama

Have run a couple of injector cleaner products through it with no noticable difference although havent towed with it yet. I have to move a few 50's Cadillacs and Buicks around on Friday so i'll put some more in and give it a work out.

Also changed the oil and filter. Used a fully synth 30 weight oil which if anything hase made it noisier. What oils do you guys use? Also used a Fram filter as it was in the truck when i got it but notice some of you guys dont rate them.

ian515

i thought we were supposed to run 40w in these things, either 15w40, or 5...am I wrong?

ptextreme

Ok I ran the bg cleaner through my system, no more black smoke, lots of power. only one problem now, my engine knock is worse. I am getting a stong fuel odor, and heavy venting from my breather tube, a loud engine knock, worse when cold, after warm up it is very noticeable over 1200 rpms, but not as much at idle. and slight vibration under accel.if it were a gasser I would say cracked piston. it sounds similar to a rod bearing. any one else have this issue, or heard of it.??????

Motorama

Yeah, i found that out after!

I've been looking into good quality 15w 40 oils. Amsoil is real expensive in the UK, $200 for 12 quarts!

I can get Rotella for a reasonable price, is it any good. Any other recommendations

MikeyB

Rotella is good oil.

MikeyB

Motorama

It turns out i cant get Rotella over here.

I can get

Rimula RT4 15w/40 mineral
Rimula R3X 15w/40 mineral

Anyone heard of or used these

MikeyB

I believe Rimula is Rotella's counterpart in certain geos (like the UK). The RT4 should be good, it's a group 2 partly synthetic.

MikeyB