"Converting gas to diesel question"

[loom02]

I have some questions on converting gas to diesel if someone could Help, I have a 2003 GMC 1500 HD 4x4 6.0L, I’m looking into a salvage 2006 K2500 HD 4x4 Duramax 6.6L. My Truck is in good shape but I want a diesel and don’t want to spend 30,000 to 40,000+ on a new Truck. One of my questions is, will my truck and the 06 duramax be pretty much A Un-bolt and bolt-on job without major problems like Engine mounting? That’s swapping Engine, Trans, Wire hardness on Engine and dash. The other question is One Truck I’m looking at has manual 4x4 mine has electric I assume that the difference would be in the transfer case if that’s it than could I just keep my own transfer case?

[DmaxMaverick]

Welcome aboard!

Not exactly a "straight across" swap. Your truck is a 2500 (non HD, regardless of what it says on the title and door badge), so it will need a little modification to properly fit the Duramax/Allison. It will need a 2" body lift, some cross member and mount adaptation, electrical harness, entire cooling stack (radiator, CAC, mounts, plumbing), fuel plumbing, drive shafts, and the Diesel instrumentation. A 2003-4 LB7 powertrain and electronics would simplify the swap, as the electrical system was changed as of 2003 (applies to all GM trucks). That said, still an easier swap than most attempted.

[loom02]

Thanks for the reply, But I ran across a used 2007 2500HD duramax 6.6L LBZ, something I didn't want to do but I fell in love with the truck, I didn't
buy it yet but working on it.

P.S. If you have any info on this model and year truck I would appreciate it Thanks.

[DmaxMaverick]

Good find, on the 2007 if it fits (or can be wedged) into your budget. Is it a 2007, or 2007.5 model? If the build date is January or later, I can't recommend it, as this was when the additional smog equipment was added (DPF), and the engine code will be LMM. If it's an early model, the engine code is LBZ ("D" on the VIN, 8th digit), and highly desired.

All said and done, you will be money ahead by NOT re-powering your 2003. If it runs well and is otherwise a nice truck (except for the gasser part), trading up (either with a dealer or private sale) can land you a nice Duramax equipped truck with much less $$ invested, and much less time and headache.

Also, the transfer case behind your 6.0L/4L80 won't work with the Diesel/HD PCM/TCM without some serious modification. The electronic transfer case (not to be confused with the electric-shift) is/was not an option on HD trucks (no "Auto 4x4" button). Not to mention durability, if you did do the mod's. The powertrain swap should include the engine, tranny, and TC. And, if you are also swapping the computers (including the BCM), harnesses, computers and instrument panel (including the 4x4 switch cluster), they will work with the equipment from the donor.

[loom02]

Well I got the truck, and it is the early 2007 LBZ, Truck is in great shape very clean but has a some mileage on it at 90,000, but seeing how the truck was well taking care of I went with it. This will be my first diesel and have a fifth wheel so I know I will like the extra power. i'm sure i'll have some
questions about the truck here and there.

[a5150nut]

loom02,

Congratulations! And you can drive it now, not after 6 months of cussing, sweat, and tears! Not to mention the torn knuckles too.

Enjoy! Oh, and 90k, just barely broke in.