LLY in a 2002 LB7 truck

[novaguy78]

Hi
I am new to this site. I am looking at buying a 02 chevy it has a 04.5 or 05 engine in it. It has never started. I seen it has the orginal fuel module and the one from the LLy engine there. I was told it needed a new computer (ECM) and harness. Would that be true. Or Could the orginal 02 ECM be programed or flashed to the specs of the 04.5 engine. Or would I need to get a new ECM and doing so will it plug into the harness or would I have to do some repining of the harness or stuff. I am sure there is a lot of open ended questions here. Ask and I can try to answer. Just trying not to get screwed in this deal. Let me know if I am going the right way with this project.

[Mark Rinker]

Welcome aboard...you have quite a challenge in front of you. How much do you know of GM diesels, control systems, wiring?

A matching LLY ECM a complete LLY compatible engine harness would be the way to start. The list of incompatibilities between the LB7 and LLY is long. Lots of information can be found here on the board in more detail, here are a few of the more major incompatibilies that come to mind between the LLY engine and LB7 chassis/wiring:

• Turbocharger and wastegate control system;
• Intake, air box, MAF (?);
• ECM, TCM (?)

Can it be done? Sure -but why wasn't the project finished in the first place? What resale value will the finished truck have, and will it be maintainable?

Unless you are getting an outstanding deal (like the cost of a used engine - maybe $5K or so) on this unfinished project, I'd keep looking...my rule of thumb on buying unfinished project cars is usually between 1/3 to 1/2 of the expected value of the finished product - and even that is variable based on how do-able the project is!!!

Q: What is the value of a 2002 Chevrolet Duramax with an LLY engine?

[novaguy78]

Ok I have a little more info. It has a complete engine harness on the unit. It has the fuel injector control module also on the engine. I Think the TCM should be ok. If it needs reprogramed I work for Allison. So no problem there. Intake looks like the same is there a big difference there? I tried to talk to Chevy today. Really got no help out of them. On place said I should/might be able to reprogram the ECM to the 04.5 engine program. If not I might have to change ECM and harness. Or at least repin my harness with a new connector to make work. Am I thinking about this right. I am not looking for resale value am looking to replace my wore out 96 1500 chevy.

Thanks in advance for the help
Novaguy

[Mark Rinker]

I moved your post to the Diesel Conversions forum in hopes of finding you some first hand experience. Afraid that my knowledge, beyond the general incompatibilites listed above, isn't detailed enough to help more...

Best of luck.