12v Cummins swap my 72 1-ton 400/727 truck

[72D3001TON]

Ok guys, I think I'm going to Cummins swap my 72 1-ton big block truck. It's a cool truck and oddly has the elusive 9' step side bed. Factory 400/727 truck. As part of this build, I'm going to run exhaust stacks on it, but run the pipes up through the wood bed floor rather than touch my nice original steps. I'm thinking 3" stacks should be fine?

 

[7mopar]

Check and see which front end they put under it. Brake master will be the clue here. If it has a 4500 lb. front end you will be fine.
There will be lots of changes that may need to be made to install the Cummins. Like possibly a complete drive line change. It would be best cost wise to get the whole dormer vehicle. So, you have everything from the radiator to the rear diff.

 

[paul massaro]

try and find a cummings core support for that body type before ripping into it , i've been told that's the hardest part to come across . don't know of anyone making those repo . had thoughts of doing the cummings conversion to my 79 w300 , it was my hold up .

 

[7mopar]

try and find a cummings core support for that body type before ripping into it , i've been told that's the hardest part to come across . don't know of anyone making those repo . had thoughts of doing the cummings conversion to my 79 w300 , it was my hold up .

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I figured you had the skills to build that Paul.
I have thought about the conversion also. I would have to change everything from the radiator to the rear axle. Just can't justify that when there are trucks out there. A Cummins with 5:56 rear gears. Now where would I go. 3:54 or 3:23 would be way better road gears.

 

[paul massaro]

my w300 has 4.56's in the drives , with had low rpm cummings it would need 44'' tall tires , lol . just to get it to cruz 65 mph on the road , but off road it would be a wall climber .

 

[paul massaro]

well costs have found a new high , just paid to have a hd 4 row core put in my d300 radiator at 850 cash with my discount , and i just did my 61 d200 seat and headliner at 2000 cash .

 

[7mopar]

I plan on starting an overdrive rebuild this summer. It may not help gas milage but maybe it will keep up with traffic.

 

[paul massaro]

we're putting a g/v od on the back of a 727 with a mild 440 for a 70 more door dart with 4.1 ls dana 60 , it should sweeten up this driver . it should lead the pack , my 69 dart gt with a hp 383 727 8 3.4 with 3.23 gear and 225/70x14's got fair fuel mileage on the road , some where around 16 - 17 mpg anywhere .

 

[65 sporty]

One of the guy's on FCBO did the swap to his wife's dually, I don't remember what year, 70 something. If I remember correctly he had a donor truck for the swap

 

[paul massaro]

you know dodge had to make a hd frame for the cummings trucks , the stock frames were cracking from the heavy duty torque and vibration . my 79 w300 had a lot of fish plating on it's frame , it's a I- beam verses a C- channel type .

 

[7mopar]

I already have a heavy duty frame. But still doesn't have that extra metal. I have a friend with one. Will have to look at his sometime. I know both cross members are also different.

 

[7mopar]

If you can find them there should be such a swap as this on the form