I'm shopping for a used Duramax, 06-07 LBZ. I located an 06 that seems clean and priced right, but per the VIN (8th digit is 2), it is an 06 LLY. I have read that the only difference with an 06 LLY and an 06 LBZ is the milder LLY tuning, that all engine and drive train components are identical to the LBZ, including that it should have the 6 speed Allison. Is this correct? If this is all correct, I am still interested in this truck, and my question becomes, how much should the fact it is an 06 LLY affect the value of the truck (as opposed to an 06 LBZ)?Second question about this truck -- It has 130K on the clock, the owner is a young guy, and he said he replaced the turbo and the head bolts at 125K. I asked why, he said his mechanic scared him telling him if the turbo blows, it will take out the engine, so he went for it, and did the head bolts at the same time. My questions are what concerns should I have about this history and this repair, and what should I look for when I go inspect the truck tomorrow?Two questions about value/resale value: First question: How much does this truck being an 06 LLY reduce the value of this 06 Duramax, compared to an 06 LBZ?Second question about value: The truck has a minor dent in the rear quarter panel. The accident shows up on AutoCheck (like CarFax), and shows a rating for similar vehicles of 81-89. And it gives this truck a 74, I believe obviously because of this minor accident on the record. I am not concerned about the dent, very minor, but my question is, how much does this affect the value of the truck?Thanks for any info!

Are you worried about driving or resale? Wouulnd't get one that doesn't have the z engine. 8th digit should be a z.The LBZ was introduced for 2006, eventually phasing out the LLY. With it came a huge leap in performance, offering 360 hp and 650 lb-ft torque.I would be worried about the body damage, and it coming from a 20 something year old!

Here are the differences. It's more than just a tune..also some heavier duty components....LLY/LBZThe LBZ (engine code "D") debuted in late 2006 and continued into 2007 sold only in the "classic" body style. It has an improved engine computer tune that produces increased power and torque over the 2005.5 LLY version of the motor. First appearance of the Duramax in the Express/Savanna vans.Changes include: Cylinder block casting and machining changes strengthen the bottom of the cylinder bores to support increased power and torque Upgraded main bearing material increases durability Revised piston design helps lower compression ratio to 16.8:1 from 17.5:1 Piston pin bore diameter increased for increased strength Connecting rod “ I ” section is thicker for increased strength Cylinder heads revised to accommodate lower compression and reduced cylinder firing pressure Maximum injection pressure increased from 23,000 psi (1,585.8 bar) to more than 26,000 psi (1,792.6 bar) Fuel delivered via higher-pressure pump, fuel rails, distribution lines and all-new, seven-hole fuel injectors Fuel injectors spray directly onto glow plugs, providing faster, better-quality starts and more complete cold-start combustion for reduced emissions Improved glow plugs heat up faster through an independent controller Revised variable-geometry turbocharger is aerodynamically more efficient to help deliver smooth and immediate response and lower emissions Air induction system re-tuned to enhance quietness EGR has larger cooler to bring more exhaust into the system First application of new, 32-bit E35 controller, which adjusts and compensates for the fuel flow to bolster efficiency and reduce emissions"

Sounds like the kid had a tuner on it or something.Be hard to tell if he did .My 07 had 110k miles on it when i traded it in and never had a issue blowing anything with efi live tuning.sounds like the kid beat the he'll out of it .Most mechanics will suggest putting headstuds on ford 6.0s.Lly had some overheating issues.Was a easy fixDepends what he wants for itbe iffy on that bottom end

crcr wrote:I'm shopping for a used Duramax, 06-07 LBZ. I located an 06 that seems clean and priced right, but per the VIN (8th digit is 2), it is an 06 LLY. I have read that the only difference with an 06 LLY and an 06 LBZ is the milder LLY tuning, that all engine and drive train components are identical to the LBZ, including that it should have the 6 speed Allison. Is this correct? If this is all correct, I am still interested in this truck, and my question becomes, how much should the fact it is an 06 LLY affect the value of the truck (as opposed to an 06 LBZ)?Second question about this truck -- It has 130K on the clock, the owner is a young guy, and he said he replaced the turbo and the head bolts at 125K. I asked why, he said his mechanic scared him telling him if the turbo blows, it will take out the engine, so he went for it, and did the head bolts at the same time. My questions are what concerns should I have about this history and this repair, and what should I look for when I go inspect the truck tomorrow?Two questions about value/resale value: First question: How much does this truck being an 06 LLY reduce the value of this 06 Duramax, compared to an 06 LBZ?Second question about value: The truck has a minor dent in the rear quarter panel. The accident shows up on AutoCheck (like CarFax), and shows a rating for similar vehicles of 81-89. And it gives this truck a 74, I believe obviously because of this minor accident on the record. I am not concerned about the dent, very minor, but my question is, how much does this affect the value of the truck?Thanks for any info!First question= yes.Second question= Not much if any at all. The ones that know this fact know the cost of a tune will get them an LBZ. The ones that don't know this don't care.Third question (second for you)= depends on how good the tech was and how good of a job he did.Fourth question= I have no idea how much a minor accident affects the value.I do know this. The LBZ sells fast and even for crazy prices. They are very sought after. If you don't buy it soon, someone else will. If you think about this for very long you won't have to think about it at all because it will be gone.Good luck.

Bottom line for me is pass on this truck. Find a true LBZ without all the mystery

Questions for LBZ experts about 06-07 Duramax 2500HD truck

carpetguy2
Explorer
Mar 01, 2014
Sounds like the kid had a tuner on it or something.Be hard to tell if he did .
My 07 had 110k miles on it when i traded it in and never had a issue blowing anything with efi live tuning.
sounds like the kid beat the he'll out of it .Most mechanics will suggest putting headstuds on ford 6.0s.
Lly had some overheating issues.Was a easy fix
Depends what he wants for it
be iffy on that bottom end
downtheroad
Explorer
Mar 01, 2014
Here are the differences. It's more than just a tune..also some heavier duty components....

LLY/LBZ

The LBZ (engine code "D") debuted in late 2006 and continued into 2007 sold only in the "classic" body style. It has an improved engine computer tune that produces increased power and torque over the 2005.5 LLY version of the motor. First appearance of the Duramax in the Express/Savanna vans.

Changes include:

Cylinder block casting and machining changes strengthen the bottom of the cylinder bores to support increased power and torque
Upgraded main bearing material increases durability
Revised piston design helps lower compression ratio to 16.8:1 from 17.5:1
Piston pin bore diameter increased for increased strength
Connecting rod “ I ” section is thicker for increased strength
Cylinder heads revised to accommodate lower compression and reduced cylinder firing pressure
Maximum injection pressure increased from 23,000 psi (1,585.8 bar) to more than 26,000 psi (1,792.6 bar)
Fuel delivered via higher-pressure pump, fuel rails, distribution lines and all-new, seven-hole fuel injectors
Fuel injectors spray directly onto glow plugs, providing faster, better-quality starts and more complete cold-start combustion for reduced emissions
Improved glow plugs heat up faster through an independent controller
Revised variable-geometry turbocharger is aerodynamically more efficient to help deliver smooth and immediate response and lower emissions
Air induction system re-tuned to enhance quietness
EGR has larger cooler to bring more exhaust into the system
First application of new, 32-bit E35 controller, which adjusts and compensates for the fuel flow to bolster efficiency and reduce emissions"
Nutinelse2do
Explorer
Mar 01, 2014
Are you worried about driving or resale? Wouulnd't get one that doesn't have the z engine. 8th digit should be a z.
The LBZ was introduced for 2006, eventually phasing out the LLY. With it came a huge leap in performance, offering 360 hp and 650 lb-ft torque.
I would be worried about the body damage, and it coming from a 20 something year old!

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Questions for LBZ experts about 06-07 Duramax 2500HD truck

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