GreyTD

Need advice from the experts. 32000 kms The truck runs great except for this annoying knock(best way to describe at this time). No smoke at startup, no codes(key onoffon check). Starting truck when cold runs fine. After reaching operating temp there is a knock(ball peen hammer hitting metal), only at low rpms (idle to about 1100)and in gear, can't hear it at higher rpms. It did this awhile ago and a diesel mechanic told me it might be bad fuel, that was about a month and half ago. Ran some injector cleaner and it went away for awhile, now its back. Have run more cleaner no help. It does it whether the edge is in or not. Air filter changed at 30000kms oil and fuel changed at 24000kms. Also have run some MMO and lucas, no change. Is it dealer time or is there something else I can check first? Forgot one thing lately under a stop light holding brake there is a large amount of vibration, alot more than before, separate problem or related? Thanks for any info.

Tony

rico334

Mine does the same thing and the ball peen hammer is exactly what it sounds like. Cold start ups it sounds normal then after warmup, the little guy with the hammer comes to life. Have had it in the dealer twice for this and they say nothings wrong.

I notice it alot louder after towing my travel trailer for a length of time, then when stopped and at idle, he lays the ball peen down and picks up a small sledge hammer I believe.

John Faughn

check for water in fuel offen, that can be done with a clear glass container , let sit for 1/2 hr. then see if there is a layer at the bottom .

Raminspeed

I had the off idle knock under load that went away after they did an injector swap #5 to 6# and #6 to #5. After the fix I picked up the truck and noticed a tick that it didnt have before I took it in, so I took it back in for that. They tore apart the engine and found a broken skirt on the #6 piston. It is now getting a new short block because of this. I hope this isnt what your problem is.

bigblock2stroke

A broken piston skirt and it was only a "tick"? Injector is bad and its a "knock". Is this backwards or am I?

Engines I've seen like that sound awful (as in rod knocking sound) when the piston is damaged due to the imbalance.

GreyTD

John I have checked for water doing what you said let stand for 1 hr it's clear.

Ram I hope not --truck runs great expect for the knock at idle when warm -- if it cold there is no knock, atleast I can't hear it.

Big Ed

My truck does the same thing. Quiet when started, knocking after warmup, REALLY KNOCKING after long tow with fiver. I addressed it at 19,000 miles and had the #6 injector replaced. The truck was nice and quiet after injector change. However, at 30,000 MILES and the same condition is back and I've chosen to ignore it because it's most likely the nature of the 305/555 and I refuse to keep having injectors replaced every 10,000 miles.

GreyTD

Big Ed -- does yours knock only when in gear or in park also - on mine the knock is there only in gear.

Big Ed

The knock is faint in park but very pronounced in gear.

rico334

Same here but I would say a good bit more than faint when in park and then very pronounced in gear. I just turned over 36k on mine so am just banking on the 100k engine warranty and then getting out from under it prior to the expiration of the warranty, but it sure is unnerving just having to listen to that tap-tap-tap all the time and thinking that it sure sounds like the engine is fixing to give birth to something out the side of the block.

GreyTD

Even with the knocking it still runs better than a gasser

redneck1

I had the same knock earlier this year. The dealership did an engine flush and it went away. Apperantly there is an injector cleaner that they pump through the motor that cleans the injectors. The dealership recommends this to be done every 25,000 miles as part of regular maintenance . When I spoke to the service manager, he said the blame is bad quality fuel, especially during winter months with #1 diesel and higher level of contaminents getting into the fuel tanks (at gas stations) such as salt. Anyways the flush was $300CAD and it is not covered by any warranty, but it did fix the problem. It's been 6 months without problems for me so may be it worked. I guess we'll see in winter.

Flyinhigh79

I have to comment on your last line. That is a horrible thing to think of but just reading that line made me laugh. I have never heard that b4, but I will use it in the future.

Raminspeed

My truck was runnig fine except for the tick/knock that I only heard when I was stoped. My knock seemed to get worse the hotter it got outside. I wonder why the block is on back order. If this was a problem I think I would have heard about it on the forum.

GreyTD

Ram I have notice that once the truck is warmed up and you stopped and shut off for not even 10 minutes then restart the knock is really noticable. Outside temp has not really made a difference on mine, not yet at least. Haven't heard or read about blocks beening on back order. Not a good sign if that many blocks are being changed.