Help Please**** LLY With A LBZ Computer Stock Truck

[Duramax 6.6L]

Hello everyone,

I just went to read a 2006 Silverado 2500 HD And could not not read it with the LLY computer selected. Truck was built in 9/2005. I used the LBZ computer to read.

Truck Built: 09/2005
Vin Number: 1GCHK39286E123110 Should be LLY Computer
OS Number: 12603624

Is this and LLY computer or an LBZ computer.

Just want to make sure I do not have a problem here before I flash new tune in.

Any Ideas on this.

Thank you for your help in advance.

[bballer182]

'06 is a funny year. in the very first couple of months of the '06 model year GM brought in a new engine a control system along with a bunch of other things. So, when the early '06 trucks were released the were released with the RPO of LLY when in fact the actual engine was an LBZ with 310hp tuning. Then the power wars demanded the that "LLY" take a new name and power rating (LBZ 360hp)

Short story...

you have an LBZ with an old RPO. the way you know if you have an LBZ is if you have a 6 speed transmission.

You can actually take your truck to the dealership and have them update the ECM programming to the latest OS which contains the LBZ tuning, for $90 in most cases. but lucky you, you have EFI Live and don't need no stinking dealer to do it!


BTW, the latest OS is 12632483, but there is no need to go any higher than the 12616128 or 12616698 OS's. Also it has been speculated that the 12632483 OS has tune tracking similar to the LMM.