File In Section: 06 - Engine/Propulsion System

Bulletin No.: 02-06-01-022A

Date: November, 2002

INFORMATION
Subject:
Information on Engine Ticking

Models:
2001-2003 Chevrolet Silverado
2003 Chevrolet Kodiak C4500/C5500 Series
2001-2003 GMC Sierra
2003 GMC Topkick C4500/C5500 Series
with 6.6L Duramax(TM) Diesel Engine (VIN 1 - RPO LB7)

This bulletin is being revised to update the models information. Please discard Corporate Bulletin Number 02-06-01-022 (Section 06 - Engine/propulsion System).

Some of the above vehicles may exhibit a random ticking noise that is most audible on an engine with a coolant temperature of 70°C (158°F) or higher and from idle to approximately 1500 RPM. The noise usually is most noticeable at the rear of the driver's side front wheel well. Customers may also comment about hearing a tick noise inside the vehicle at idle such as when sitting at a drive through window. All 6600 Duramax(TM) diesel engines have this condition; however, some are more audible than others. Engine build variation from engine to engine contributes to differences in perceived volume. All Duramax(TM) engines are manufactured to very close tolerances to meet the durability and reliability standards.

This noise is caused by the relationship of the engine cylinder block, crankshaft journals, bearing inserts and the oil film. This relationship may allow a vibration that resonates through the cylinder block and is heard as a metallic ticking noise. The noise could be described as an irregular ticking or clacking sound, like random typing on a mechanical typewriter.

This condition has been present in diesel engines produced for the last 20 or more years. The overall noise reduction in engines produced today makes this noise seem new when, in fact, it was masked by other noises in the past.

Many manufacturers such as Isuzu, Hino, Mitsubishi, and Nissan report a similar condition in their diesel engines. Testing and engine teardowns with this condition reveal no condition that would affect reliability or durability of this engine.

Dealers should not attempt to compare any customer vehicles exhibiting this noise with other similar vehicles as the noise is different from vehicle to vehicle and this may lead to the incorrect conclusion that the vehicle has a condition. This noise is a normal operating characteristic of the engine. This noise has no short or long term effects on the engine. Do not attempt repairs for this noise.
Important: Replacing the engine or internal components for this noise will not reduce or eliminate the noise.

Edited by: Mackin

Mine sounds like a valve ticking or a lifter.

i have a 2001 8.1 gasser that ticks, and a 2002 caddy dhs northstar, that ticks,


but my 6.5 diesel doesn't, 178,000 miles. go figure

Mine has that weird ticking sound - I didn't have the tick on my '03 but my '04 has it and it's really weird...


it's almost like something is wrong with the motor or there's something ticking around... anyhow...


HAPPY NEW YEAR ALL!

Mine ticks quite a bit, and I'm trying to relate it to low oil pressure while idling, when engine is at full temperature. Anyone with a tick, what do you run for oil pressure when idling hot? How many miles on your truck?

My truck has like 3800 miles on it and had it's first oil change and still ticks. Oil Pressure is like 40-60lbs at idle.

Give your new oil about 2000 miles. Mine stopped after that. Doesn't make much sense

I'll see what happens in 2K miles then. I wonder if synthetic makes a difference??? I plan on changing all the oils over to that

My dealer tore my truck apart to find it. Dropped the tranny ect... Then notified me about this bullitin. Not a happy camper at the time.


On the Good side --The noise did go away!


14000 miles just had 4 injectors replaced. Thats another story.

I have a ticking noise in my '95 C3500 6.5l Turbodiesel with only 49,000 miles. I just posted in the 6.5l forum before I found this one. Mine just started about a thousand miles ago and sounds like a valve train noise. It appears to be coming from the right rear cylinder closest to the firewall. Am I to believe everything is "O.K."????? That's a hard one to swallow!! Chuck

I have a ticking noise in my '95 C3500 6.5l Turbodiesel with only 49,000 miles.. Mine just started about a thousand miles ago and sounds like a valve train noise. It appears to be coming from the right rear cylinder closest to the firewall...


Chuck,


Check to make sure you injector lines are not touching any other parts. On the 6.5 an injector line "touching" can cause the type of noise you describe.


http://www.dieselplace.com/forum/smileys/Geek.gif

I have about 7500 miles on my '04 and it sound like.....well, a typewriter....


Make's me feel alot better that GM says its normal.http://www.dieselplace.com/forum/smileys/Ermm.gif


Jesse

My '02 did it for the first 8-10k miles, then it quit completely. It started back at about 19k miles...


20k now and it's still tickin' away.http://www.dieselplace.com/forum/smileys/HiHi.gif








Kevinhttp://www.dieselplace.com/forum/smileys/Big Smile.gif

Mine still does it, I just ignore it now but it sure drove me crazy at first. My dealer didn't know what it was either, but I found out about the problem online at the RV.NET site.


Never told the dealer I guess I should so they will be informed when the next person comes in with the same problem.


Thanks for the detailed explaination.

My tick comes from the mount between the manifold and the exaust pipe. My neighbor says he can here it 1/4 block away.

Bill(jpblock)


You got it!!http://www.dieselplace.com/forum/smileys/Clap.gif Aluminum coolant line touching injector line. It was probably bent during FI pump replacement. I tweaked it and I'm back in business...no more "funny" noise. Thanks, ChuckEdited by: Worksmart

I heard this last night when i was at a drive thru window and got worried so when i read what you guys and GM was saying it makes me feel better.


Just think if we didn't have place like this, what would the dealers do to our trucks trying to find these noises.

I only have 400 miles on my truck, however there is a goofy ticking noise at about 1500 rpm. After that, the turbo winds up and you don't hear it until you shift and get around 1500 again. Makes a guy scratch his head a bit, but I have to wonder if the tick will go away with break in time, or is it an omen of things to come.....Until it grenades, I'll ignore it...The turbo is more fun to listen to anyway..

Mine makes the same noise too, usually when the engine is warm though.

I had the same ticking noise in my 01 D/A untill I added Primrose 405 and it went away after 15 or 20 miles.


I'm a happy camper now!

TSB sounds about right. Folks hear it on cell phone remote microphone, even up to 2300 RPM. Ticking sound got louder with time on engine, and time on the oil change.

Edited by: turnpike

My 2003 started this noise at 400 miles. I was up under my truck with a stethosope for several days trying to pinpoint the noise. The dealer didn't have a clue.


The dealer finally told me it the the pump in the Allison and would not have any affect on reliability. I am glad I read this TSB. I have pulled up beside many trucks with the duramax and have heard several others with the same condition. I did feel better knowing mine was not the only ticker. I am not happy with the noise but I guess we will have to live with it.


8500 miles now and it still ticks like it did at 400 mi.

my tick went away at about 20K, started at 500 miles on oil changes and progressively went away. It comes back every now and then but only briefly.

I'm wondering if the Tick has anything to do with bubbles in the oil being squashed under pressure and if the oil pump is causing some cavitation?


I wonder if an antifoaming agent may help.


Clues to the noise are: It doesn't do it cold and only when warmed up a bit, SInce the oil is slightly thicker when cold it may resist cavitation. Different types of oil may lessen the ticking as well but I have not owned mine long enough to experiment.


Just some thoughts


Rob

my brand new o4 lly ticks gm may call that normal but i dont

It will most likely go away. I wouldn't sweet it. We've all been there. No one has experienced problems yet.

It's normal. It doesn't sound normal and I'm sure Isuzu didn't design it to be there but they researched it and found it to be only an annoyance. Think about being a powerplant designer. It's almost impossible to predict what and all new design engine will sound like until certain tests and prototypes are built. And i don't mean exhaust sound but the actual metallic sounds of the parts interacting while working. Eliminate all combustion noise and you will hear all kinds of other cool sounds. Lot's of interactions going on once the whole thing starts running including temperature changes and how it effects oil pressures and metal expansions. This is where they say the tick comes from... high oil pressure and oil flow. When you force a liquid through a galley at pressure then you change it's direction and/or working space.... you can cause it to cavitate (release air or open up vacuum bubbles). Isuzu claims that is the noise you hear and it's amplified by the block (I presume). Once these pockets get "smashed" by detonation/bearing compression... you get a snap.. likened to popping a bubble gum bubble.

General Engine Co. who makes the 6.5Turbo Diesel uses a unique quality control check in their assy line to inspect each engine for proper torque and assy. After it's assembled.... complete rotating assy, no oil pan... they have a special oil pan shaped microphone that drops on the bottom of the engine (it's upside down at this stage). Then they pressurize the oil system and spin the engine. A perfectly built engine makes a particular set of sounds. A computer compares the sound to a known good pattern. If a bearing was installed improperly it blocks air going through the crank oil galley so the sound is different. If something in the valvetrain isn't right that also throws a flag.

Sorry for going out on this ... but sounds play an important role in diagnosing problems.

That's why the tick bothers us so much at times. It doesn't seem normal but it's most likely something Isuzu couldn't predict and doesn't feel needs to change. It may be a pretty expensive effort so they just deal with it.Edited by: hoot

When it stops knockn' - you start walkn' http://www.dieselplace.com/forum/smileys/Big Smile.gif

I noticed mine ticking recently on a 20 mile roadtrip to get some parts....I was running about 60ish(w/285, speedo calib to 265) so was running a bit above 1500rpm, i think 1700-1800...prolly the only reason its off from the 1500 is the different tires??? Oddly enough it goes back and forth. I heard it for like 60-70 miles then nothing for a week then back....never heard it at an idle either....nice to know its "suppose" to be there....

if i hear the "ticking sound" I'LL BRING MY BADBOY IN TO THE DEALERSHIP and have a record of the ticking on file. so down the road if a problem happens or something is found i can go back and say look at the serv. record

I have a Calif LLY and no knocking noise that I can hear yet.http://www.dieselplace.com/forum/smileys/Big Smile.gif I have a 62 Impala with a rebuilt 327 gasser. I had a knocking noise after I had it rebuilt. I was able to determine which cylinder it was coming from by disconnecting the spark plug wires one at a time. It was piston # 6. Probably piston slap. Try disconnecting the fan belt and see if the noise goes away. Could be a water pump, a/c compressor, etc. etc. Anyway, I changed over to Mobile I synthetic and the sound went away after a month or so.

This is unacceptable. I have a 2002 Duramax with 35,000 miles and the thing still ticks. Currently has Mobil 1 synthetic, but has ticked with all types of oil. I am a mechanical engineer and understand the logic behind the tick, but do not buy it at all. When we pay $45,000 for a truck the son of a b~~~h better not tick. Even if the ticking does not hurt the motor it needs fixed.
I also do not believe GM because I have a 2002 Camaro SS 35th aniversary editon with an ls1 I use as a show car. The car only has 1,100 miles on it and it knocks. The culprit is piston slap. GM trys to say that piston slap is normal in an engine BS, and they will do nothing to fix the car.
Somebody at GM needs to die. I have spent $80,000 on their products, and they don't want to stand behind them.

I agree with ssnightmare...whenyou pay 45,000 dlls for a truck it better hold...this ticking is driving me insane...

Not to rub it in, but I guess that I am lucky because I don't have a tick. I do agree that when you buy a $36,000 + truck, it better be right, and they had better stand behind it.

I heard this last night when i was at a drive thru window and got worried so when i read what you guys and GM was saying it makes me feel better.


Just think if we didn't have place like this, what would the dealers do to our trucks trying to find these noises.
This is an old thread I know but I experienced this at the espresso joint this morning. Freaked me out because I just installed the edge last night. I only have 600 miles on it and ran the edge once. Plan on leaving it off till I get my first oil change in. Anyway. I was wiggin out. Till I came here and found its "normal" So a bit :ro) to having this forum to share info with.

Im a first time duramax owner and i was sick to my stomach when i heard the ticking at about 300 miles. I took it to the dealer and they promised me it was normal but they were going to put it on my records for possible future problems.Still not believing the dealer i discovered this site and am relieved other people have this even though i still am upset my $40,000 truck ticks ....Thank you all for your help.

I have an early '01, been ticking for 4 years, never an issue, no worse, no better just take a lickin and keeps on Tickin LOL :lol: :lol: :lol: :lol:


Don't sweat the "tick" theory is that it shows the engine is still "tight" and not broke in yet, I am at 47K and everytime it "ticks" just reminds me it's as tight now as it was new. I'am not going any further with that comment cause there's guys around here that will have a field day with it.
:lol: :lol: