LLY vs LBZ ??

[FBJR]

Looking at the DM and want the LBZ (360hp) but have found several LLY (310hp) too with the same options.

I have heard the LLY is a detuned LBZ, and have heard they are diff motors all together? LLY was availible until late 05 and now everything is the LBZ.

So does anyone really know the diff??

THX

[dozerboy]

The 06 LLY and LBZ are the same motor just different tuning. All and only the 06s have a 6 speed ally, cooling mods, fan, shroud, ETC, 32 bit ECM, lower compression, stronger block, and pistons that is the just of it. You can tell the 2 apart by the 8th # in the vin it is a “D” on the LBZ. The 05s and earlier LLYs and LB7s are different.

[ChevyMan02]

When did the LBZ come out? Does gm offer it as a more powerful motor compared to the LLY or is it a diff.(better) design also?

[FBJR]

Thanks DB, that is what I believed too.

Quit a few sites out there with the info showing when the 2 were availible with the LBZ being the latest.

Since I am going to tune it anyway, why not save a few $ and get more rebate too!

FB

[dozerboy]

Originally Posted by ChevyMan02

When did the LBZ come out? Does gm offer it as a more powerful motor compared to the LLY or is it a diff.(better) design also?

Its all in my post in stock form the 06s are better. How did I forget the 06s also have a larger turbo too.

[thecodeman]

The 06 has a variable geometry turbocharger. I suggest reading this page, it's always been an accurate, reliable independant source for diesel info.

http://www.thedieselpage.com/duramax...ewsrelease.htm

[FBJR]

Called Banks today and they said the LBZ and the LLY are diff motors. They can tune an LLY more, but the LBZ will still make more power.

I had already read the above but they really dont say what the diff are between the 2.

Hmmm, FB

[thecodeman]

Originally Posted by FBJR

Called Banks today and they said the LBZ and the LLY are diff motors. They can tune an LLY more, but the LBZ will still make more power.

I had already read the above but they really dont say what the diff are between the 2.

Hmmm, FB

That whole page is about the changes made to the duramax for the LBZ. Here's a page on the LLY.

http://www.thedieselpage.com/duramax/lly2004.htm

[FBJR]

Finally found something that answered my question. There are 2 LLY series motors. I want the 3 (LLY 06) or D (LBZ)

Engine Identification:
The Duramax engine has evolved from the original LB7 series to the LLY series, and now the LBZ series. The LB7 was used from 2001 model year until mid 2004 model year. In mid 2004 the LLY was released. In 2006 the Duramax changed again. The early 2006 engines were still called LLY and the alter 2006 became the LBZ. This creates some confusion as the 06 LLY is distinctively different from the 04.5-05 LLY. The 2006 LLY and LBZ engines are essentially the same when it comes to modifications. The simplest way to verify which series you have is the VIN# of the truck. The 8th digit is the engine ID and it will either be a 1, 2, 3, or D.

01-04 LB7 is a 1
04.5-05 LLY is a 2
06 LLY is a 3
06 LBZ is a D

Example: 1GCHK29143Exxxxxx for LB7 and 1GCHK29243Exxxxx for LLY. It is important to know this as while the engines are essentially the same at the core, the electronics, turbochargers, electronics, and injectors are different among the variants.

FB

[thecodeman]

Ah, I thought you just wanted to know the differences between the LLY and LBZ

[FBJR]

I knew the basics but wanted to know how to tell them apart when buying too.

LBZ for sure now!

FB

[dozerboy]

Like I said the 06 LLY and LBZ are the same just different tuning and the other LLYs are different. The easiest way to tell the LBZ apart is the badges the LLY has the same old Duramax Diesel badge and the LBZ has a Duramax Allison badge. You still need to check the VIN as a lot of guys are sticking on the new badges on there none LBZs.

[FBJR]

I was looking at a new 06 with a "2" vin meaning an older LLY.

FB

[Superpug]

So whats the dif between the 01 and 06. My dad has the 01, it was the first one in the DFW area. how tunable is it, cause itll probly be my college vehicle.

[LostBoy]

Originally Posted by Superpug

So whats the dif between the 01 and 06. My dad has the 01, it was the first one in the DFW area. how tunable is it, cause itll probly be my college vehicle.

They're all good, and there's not much limit on what you can do to any of them, although availability of aftermarket stuff on the 06 trucks is slightly limited as a lot of the tuning companies are still decoding them, but there's still tons out for even that.

[dozerboy]

Don't run any tune that will add more than 90HP without a tranny upgrade on the 05s and older.

[LostBoy]

Originally Posted by dozerboy

Don't run any tune that will add more than 90HP without a tranny upgrade.

Agreed - Allison won't hold more than 100hp over stock, so you're pushing that limit if you go over 90hp

[Durden]

Allison won't hold more than 100hp over stock being all Allison tranny's or just the 05 and older 5-speed previous model Allisons?

[dozerboy]

LB7 90, LLYs 60, and LBZ 40, this isn't 100% be most seem to be OK at these power levels.

[duramaxin14]

superpug u can crank the power out of the lb7 just like any other diesel just wacth out for that stock ally she wont like it to much