Can you tell if a truck has and LB7 or an LLY engine by the serial number? I am looking at a purchasing a truck about 400 miles away from my home so opening the hood and looking is not an option at this point in time. I assume the serial number for the truck has a letter code for the engine. If so do any of you know which position and letters stand for the LBY and/or LLY? Thanks.

8th digit of the VIN

1 = LB7
2 = LLY
D = LBZ

Exactly what I needed to know. Thankyou. :)

the 2 has two possible options. the 06 had 2 model engines the 2 lly, and d lbz. they both use the exact same block and related parts but the programming is differant. the 04.5-05 lly are completely differant from the 06 lly. just thought you should know.

Good to know, thanks. The truck I am looking at right now is a 2004 and has the "2" engine code.

yes that is the original lly. great engine. although many have had over heat problems with them. if your not towing huge weight then i would not worry.