[BigBadAllis]

At approx 10,000 miles and just after I got my truck out of the shop for the power steering/brake repair, my engine suddenly develpoed a steady clicking or ticking noise while idling. I mostly notice it when the engine is colder. I haven't noticed it before. Shoud I have it checked out or is it normal?

Thanks,

 

[bonz02]

Does it sound like a "typewriter", mine has developed the "typewriter" noises at idle too, but I think I read somewhere that it is normal and may come and go?

 

[gfd464]

I developed the same sound!!!!!

Update: Just found this http://www.alldata.com/tsb/General-Motors/1167465600000_1166515200000_02-06-01-022F/2061.html

 

[BigBadAllis]

I developed the same sound!!!!!

Update: Just found this http://www.alldata.com/tsb/General-Motors/1167465600000_1166515200000_02-06-01-022F/2061.html

The above sums it up. Thanks for the information.

 

[Riccas]

Yeah the TSB says its common... anyone know what actually causes it though??

 

[1BADSL]

Well that is good to know. Mine also has the ticking noise, but my last did not. However it is good to know that I can type faster than my truck.

 

[Hulk76]

Feeww! Just got the truck last Friday and it was pretty cold. The next day, I start her up, its somewhere around -26 outside and I start hearing this. Now I start saying to myself, noooo, out of 1million perfect trucks I get the one that is a lemon, but after reading this, WHAT A RELIEF! This place rocks, sure helps me sleep. :rockit:

 

[MGlickLBZ]

Found this. I have it also. My truck types faster than me though.....

http://www.alldata.com/tsb/General-Motors/1167465600000_1166515200000_02-06-01-022F/2061.html

 

[woodchuck2]

Mine has it and i have never worried about it. The truck runs fine and had no other problems. The noise comes and goes, sometimes quieter than other. If i had no oil pressure then i would worry. If it aint broke dont fix it.

 

[mtklamo]

Just changed to synthetic and it really types fast.

 

[KBBrett]

I asked the shop foreman at the Chevrolet dealer about it, and he said it is caused by air bubbles being popped in the bearings under pressure. Mine seemed to be more noticable since switching to Mobil 1.

 

[Evil_C5]

can someone cut and paste the TSB in here, it says i have to be a member of alldata to see it.


thanks!!!!

 

[GMCLBZ]

I can't locate my bulletin print out right now, but it does say it's because oil bubbles and it is nothing to worry about. i just did my 1st oil change ( Amsoil 5W/ 40 ) and it does tick a little faster at times. now that it's documented for being at the dealer for that I'm not gonna worry about it.

 

[Rosey]

can someone cut and paste the TSB in here, it says i have to be a member of alldata to see it.


thanks!!!!

As I recall there is a TSB on the Duramax LBZ that tells the dealers that the ticking complaint by customers should be considered "normal" and that no furthur action is warranted.

 

[ibfarmerduramax]

Here is a copy of the GM bulletin:

"A random ticking noise may be heard in some LB7/LBZ's with the engine running at idle speed and with the coolant warmed to a temperature of 70 degrees Celsius or above. An Irregular metallic ticking/clacking sound like random typing on a mechanical type writer, can be heard at the lower rear of the left front wheel house. Some customers may also hear the noise inside the cab as well. This irregular ticking/clacking sound can be heard between idle and 1500 rpm. Above 1500 rpm the sound goes away, but returns once the engine is operated within the idle and 1500 rpm speed range.
The sound is caused by the relationship created from the engine block, main bearing crank pin, bearing inser, and oil film which generates a vibration that resonates though the block and is heard as a metallic ticking noise. This noise is most audible on vehicles that have engine main bearing tolerances that are closer to the minimum main bearing clearance specification. All Duramax engines have this condition, however some are more audible than others. Tolerances between nonaudible ticking engines and audible ticking engines are differences in clearances measured in microns.
Isuzu advises that they have experienced this condition in other diesel engines they manufactured over the last 20 years. Other manufactures of diesel engines such as Hino, Mitsubishi and Nissan also report similar noises in their engines. The LB7/LBZ bearing manufacturer has investigated this noise in the LB7/LBZ and state that no reliability or durability concerns are due to this condition.
General Motors Noise Vibration and Harshness group and Isuzu of Japan Engineering have done extensive testing and agree that no reliability or durability of this engine is effected by this issue. GM engineering has run a ticking engine on a 1200 hour dynamometer durability test and has also agreed that the noise condition does not effect reliability or durability of the LB7/LBZ engine.
The noise is a normal operating characteristic of this engine, It has no short term or long term detrimental effects on the engine. Do not attempt repairs for this sound."

 

[Evil_C5]

thanks!

just wanted to make sure it wasnt something i should worry about.

 

[2046]

Drive it like you stole it it's ok !

 

[feetfats]

My truck ticked right from brand new,, I got them to replace the serp belt and the problem was instantly fixed. The warrenty even paid for it