5.7L Vortec ->6.5L Turbo Diesel swap?

[ndians68]

the only problem with the dmax would be all of the computer stuff, and tranny stuff, personally i would go with a 12 valve cummins, for simpicity. the dmax is a great motor, but has way to much comper controlling stuff, and would need some mods of the frame rails to fit

for the transmission i would say go manual, mostly because that would be easier, but if you don't want to be shifting gears, be ready for a wiring night mare (as if you already won't have one) also i would sugest going ahead and building it if you plan on doing anything extra to the dmax for performance.

you will probably also need a different tc, not for sure, i guess the stock one might work, but will need to be beefed up for all that extra power.

the rear end you might as well switch it to the dmax rear end, i don't see even a 14 bolt holding up that the power of the dmax that well

this is my personal guess, either way its going to be expensive, and a lot of work.

 

[SAATR]

It's fairly simple to get a plug n play harness for a Dmax that already has all of the unnecessary leads removed to make the wiring easier. It is not, however, cheap. Not to mention that you'll need to interface it to the wiring of your truck. The engine and transmission are also expensive, with the cheapest engine/trans combo I've seen being about 5k on ebay right now. That being an LB7, which had their share of issues being the first run of Dmaxs. There are several forums devoted to the Dmax, and lots of conversions, so I would say that if you feel the interest, seek them out and get first hand experience.

 

[skylark]

I own the 6.5 as well, and for mpg you have to keep it under 2000 RPM. That equates to 58 mph with my 4.10's. When it dies a Cummins 6BT will be filling the engine bay. Also 94 was the first year for the electronic 6.5 (DS4 pump, the 93 and earlier had the DS2)

 

[ndians68]

and if you do end up with the LB7, be planing on replacing injectors atleast every 200kmiles, or in most cases 100k, just depeneds on how lucky you are. just guessing , but LBZ (the best dmax made) would probably run you around 8k, maybe a little less if you searched enough.

 

[outalne94z71]

I own the 6.5 as well, and for mpg you have to keep it under 2000 RPM. That equates to 58 mph with my 4.10's. When it dies a Cummins 6BT will be filling the engine bay. Also 94 was the first year for the electronic 6.5 (DS4 pump, the 93 and earlier had the DS2)

my 98 crew dually 6.5 gets 18 on winder blend and low to mid 20's on summer blend

 

[skylark]

my 98 crew dually 6.5 gets 18 on winder blend and low to mid 20's on summer blend

What speed are you running? Tire size?
I know that I was hauling balls but at 75 the best I could pull was 13. Granted the truck had some issues that we were dealing with but at 75 or so it was 12.8-13.2. Don't get me wrong. I do like the 6.5 and I don't feel that it is a bad engine but I do like the 6BT better. We bought the Chevy because we liked it, I wouldn't park another Dodge in my driveway after the bad luck that I have had with the previous ones that I've owned.

 

[outalne94z71]

i usually run around 60 most of the time, drive like a grandpa, i have the oddball 215/85/16 range e(factory range d) for tires, i have the N/A heads on mine and a home made turbomaster with gm-8 turbo ,and my tdc set to -5.4

 

[skylark]

Why the N/A heads? Your tires are slightly shorter than mine (235/85/16). I've heard the turbomaster usually has lower MPG than the vacuum wastegate. I have to admit that I'm envious of your MPG.

 

[outalne94z71]

Why the N/A heads? Your tires are slightly shorter than mine (235/85/16). I've heard the turbomaster usually has lower MPG than the vacuum wastegate. I have to admit that I'm envious of your MPG.

i had gotten a 506 block crate motor that had 20k miles out of a 80's k5(for $500), it was a n/a version with the smaller precups and no piston squirters, n/a heads seem to get a little better mileage so i had left them on there after first checking them, at the same time i put on a brand new injector pump and turbo so the whole thing was pretty much new

if you set a tm too high you will get worse mileage, mine is set to where i have to really work it to hit 10psi and seems to be best where i have it set right now

 

[Fobroader]

Theres a guy on this site who swapped in a 12V Cummins into his Suburban. THat would be my vote, simpler than the Dmax and way cheaper, as for the reliability of the engines, Im not going to start a pissing contest......If you really want a reasonable swap, the cummins is the way to go, just my $0.02.