To Dmax, to to not Dmax?

legendaryandrew

Adventurer
I've been debating swapping a Dmax into my NBS 3/4 ton suburban for about 2 years now. Lots of pros (mpg, power), lots of cons (cost, cost to fix). I've talked to the guys at duraburb, and as swaps go, it's pretty easy. 1-2 inch body lift to clear Allison, bolts to the same mounts my 8.1 uses, for the most part plugs straight into factory harness. Parts would be easy if I got a clean enough insurance total. And based off of my rough math, it'll justify itself cost wise (assuming nothing catastrophic happens) after 50k-75k miles, at current gas prices, 8.1 currently gets an average of 10mpg and most of the mild tuned Dmax guys I know claim 18-22mpg. Anyway, opinions? Truck will be a road trip/camping/light expedition vehicle. No heavy wheeling, also paid off so no plans to sell.
 

ZMagic97

Explorer
Do you plan on keeping it for some time? If so, the Duramax will be worth having. If you son't mind the 8.1 mpg, then you can't lose either way.
 

legendaryandrew

Adventurer
Haha if the swap happens, the 8.1 is going in a late 70's Silverado 😆 as for justification, I suppose you're right, but I've spent over 100k in mods on various sports cars over the last few years...one thing I learned is doing it right the first time is cheaper, and there is such thing as too much.
 

Larry

Bigassgas Explorer
screwy.gif
 

plainjaneFJC

Deplorable
I don't care what button you press on the calculator it will never make sense. But who cares, a dmax in the burb would be cool. I am assuming an old lb7?
 

1stDeuce

Explorer
I agree, you can't "justify" something like this. You can want it bad enough to have it done though. :)

I have a dmax in my current truck, and I'll likely be keeping it for a Looooong time, but when the time comes to replace it, I will likely not go shopping for another diesel. They're great in the mountains, and if you insist on pulling huge loads at posted speed limits, but the maintenance cost is fairly high if something does go wrong, and mileage gains are at least partially offset by higher fuel prices. Though if you're even considering this swap, neither of those are concerns. :)

For the money, if you just want to rip a bit more, I'd look into a supercharger. :) I think a 6.0L with a supercharger would be ideal, as best mileage empty plus insane torque when needed, but since you've got an 8.1 already, go with it! :)

And if you're trying to put a dmax in for "cool factor" to impress people, you're probably better off putting the money in a classic muscle car... Unless you go with some sort of annoying Bro Dozer exhaust (Please don't!), a dmax in a Sub is a sleeper, and won't get you nearly as many chics as a '69 Camaro. ;)
 

legendaryandrew

Adventurer
The maintenance costs were a concern. I can just about rebuild my 8.1 for the cost of a Dmax injector pack. And you sure can justify this kind of thing, as it just about doubles the vehicle range, which is a fairly big deal in something being built for expedition use...and modifying things is a bit of a hobby.
 

Larry

Bigassgas Explorer
The maintenance costs were a concern. I can just about rebuild my 8.1 for the cost of a Dmax injector pack. And you sure can justify this kind of thing, as it just about doubles the vehicle range, which is a fairly big deal in something being built for expedition use...and modifying things is a bit of a hobby.

Nah, range isn’t as big as deal as many of the Indiana Jones hat weary expo types here on this website lead it to be. Seriously, where in the lower 48 can you go that you cannot carry enough gas in a few cans to get you out again? My 8.1L K10 has two 16 gallon tanks and I carry two 6 gallon scepter cans. The truck has been all over the southwest from the innards of Death Valley to the middle of Canyonlands and never once came close to running out of fuel even after being out there roaming around for several days. The nice thing about the manual trans though, is I can let it lug around at idle in 3rd gear and crawl about anywhere in the desert while getting pretty decent fuel economy for a big *** gasoline powered rig. Automatics will eat more fuel just spinning the torque converter and needing to tip into the throttle to just keep the rig rolling at 3 mph.

As far as diesel swapping, there is no real justification for swapping one outside of just flat out WANTING a diesel. That’s it… fuel economy is moot, and range is moot and depending on the engines power can even be moot. Modern diesels aren’t even the high life 300,000+ engines they once were. These days one can get more durability out of a gasoline engine. Watch the medium duty truck segment the next few years. You will see Ford, GM, Freightliner and International all offering gas engines in their big medium duty trucks just like back in the 60’s, 70’s and 80’s. As I’ve said many times before here on Expo, I work for a diesel engine manufacturer and I would not own a modern diesel engine. Deal with the junk every day. They would be okay to swap into something like a boat……for an anchor!:snorkel:
 

shortbus4x4

Expedition Leader
Yeah what Larry said. I've already seen fleets changing back over to gas engines. I work on modern emissions diesel engines for a living and I wouldn't own one. Now I do have a soft spot for 24 valve VP44 Cummins and would own one in a heartbeat.
 

ninja218

Sgt of Marines!
Quick quez why not go with a 6BT instead of a DMax? Like you i have a k2500 with a 454 and Diesal seams better but not sure which one to use.
 

legendaryandrew

Adventurer
On NBS gm trucks like the burban, the Dmax goes in without any custom fab work. Bolts straight in, plugs into (for the most part) the factory harness, which retains all factory gauges and info computer functions.
 

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