2005 LLY programming/tuning

[cowboypilot]

I have a 2005 3500 4x4 SRW that I bought about 2 1/2 years ago with 90,000 on it, I'm about to hit 150,000.

I have a fairly strong reason to believe that the computer on this truck has been programmed, for two reasons, one it has a lot of power compared to stock duramaxs I have driven and second when I bought it the truck already had a AFE intake and exhaust and there are hookups for EGT and boost gauges already (who would go through all that and not do anything to the computer?).

What it really boils down to is I want get more MPG's out of this truck (I consitently get around 16 mpg) and I'm wondering if this thing has been programmed for power or if it already has an economy tune on it. I am thinking about getting a chip or tuner and don't really know where to go from here, need some direction from someone who knows more than me!

Thanks

[DmaxMaverick]

Keep it simple. Buy or otherwise obtain a "core" PCM. Send it to Kennedy and have it programmed. He can guide you with your needs from there. Then, you can swap PCM's as needed, and investigate what you have now. If you have no idea what is in your original PCM, adding a program or "chip" could be disastrous. The dealership can return the PCM to its original programming.

And...While is isn't common, people do "bolt on" stuff without adding computer upgrades. An intake/exhaust upgrade on a 2005, in itself, can help with overheating issues.

[Kennedy]

It's really tough to know what may be programmed on your truck, and that is in my opinion worse than stock. You just don't know what you have or where you are. Just about all off the shelf LLY programming is one sided. Fuel only and no boost. This makes for high EGT etc.