Not to sure since i cant hear it, but mine makes a intermitent ticking sound! The lbz is such a quiet engine you could be hearing and injector or anything else, wish i could be more help. Let me know what turns up with the noise hopefuly nothing but still curious??
I have now 3650 miles on it,started at about 700 miles i did a oilo change at 1500 miles,still there.ticks at idle but only warm from about 165-170,not at first start up.If i run it hard and get the temp to about 200 its quiet,till i let it idle and cool a little then it ticks again.I have not towed with it yet.
i have an 06 LBZ and can also hear a ticking noise coming from the left front fender well area at an idle on occasion. Engine runs fine though. I would think its valvetrain rather than an injector. It doesnt seem to sound catastrophic. Im somewhat concerned thought thats why was curious to see if anyone else had seen this problem. I havent been to the dealership yet. Let me know if you find anything.
Subject: Information on Engine Ticking #02-06-01-022E - (01/12/2006)
Models: 2001-2006 Chevrolet Silverado
2003-2006 Chevrolet Kodiak C4500/C5500 Series
2001-2006 GMC Sierra
2003-2006 GMC Topkick C4500/C5500 Series
with 6.6L Duramax� Diesel Engine (VINs 1, 2, D -- RPOs LB7, LLY, LB7)
This bulletin is being revised to update the model years. Please discard Corporate Bulletin Number 02-06-01-022D (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� 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� 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.
Please share the information found in this bulletin with customers who inquire about this condition. In the event they have additional questions or concerns, please advise them to contact Customer Assistance at the numbers listed below for further information.