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Discussion Starter · #1 ·
So I have a 1978 K30 that I was planning on swapping a 5.9 into. I know this is a pretty common swap and have no problems with the physical swapping or compatibility just had a question about the Gen 1 vs Gen 2 Cummins. In my area I am having a really hard time finding a gen 1 5.9 to use for the swap but have a pretty easy time finding gen 2 engines / totaled trucks. I was planning on using a NV4500 for the tranny and was just wondering what I would need to complete the swap as in electronics wise and or any other tips. Don't really mind if I can keep the 4 wheel drive or not. I just know with a gen 1 that its crazy simple on the wiring side, just not to sure how the gen 2 is because I'm assuming I'm going to need a pcm, ecm, or some of those works. I was planning on rebuilding the engine myself (fresh gaskets and just check and fix any clearances) so if there is anything I should do there please let me know. Just kind of curious if I'm worrying too much about what I need for a gen 2 swap or if it's worth it to go out of my way to find a gen 1 to put in it. Thank you.
 

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The only thing that a 12v needs to run is fuel and power to the fuel shutoff, unless you use a cable shutoff then it needs no electronics.

I moved this to the Conversion section where you can start a build and ask any questions and show pictures.
 

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Discussion Starter · #3 ·
The only thing that a 12v needs to run is fuel and power to the fuel shutoff, unless you use a cable shutoff then it needs no electronics.

I moved this to the Conversion section where you can start a build and ask any questions and show pictures.
okay so you're telling me that like I found this 1996 2500 with a 5.9 and If I plucked the engine out all I would need is Fuel, alternator wiring, fuel shut off wiring, and starter wiring?
 

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okay so you're telling me that like I found this 1996 2500 with a 5.9 and If I plucked the engine out all I would need is Fuel, alternator wiring, fuel shut off wiring, and starter wiring?
And gridheater wiring and solenoids, radiator, intercooler, exhaust. The best way to go on the alternator is a 1 wire or a external regulator.
 

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Discussion Starter · #5 ·
And gridheater wiring and solenoids, radiator, intercooler, exhaust. The best way to go on the alternator is a 1 wire or a external regulator.
Well that was a whole lot simpler than I thought it was going to be. I think ill be yanking a 5.9 out of a junkyard now instead as I can get a longblock for $400 lol. Thank you so much Ill make sure to show pictures as I go. I also saw this YouTube channel by the name of Sam's trucks that showed me a 1 wire alternator I will most likely go with. One last question though I saw some people use intercoolers and some people skip over it. what are the benefits or drawbacks of each one. Thank you again.
 

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If you do heavy towing the IC will benefit you, I squeezed one in front of the radiator on my 84 K5 Blazer.

I use a 1 wire alternator from PAPERFORMANCE on my 96 F350 with a 12v, makes a nice clean install with less wiring.
 

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What tcase do you have now?

The downside of the 2ndgen dodge donor is you don't get a passenger-drop tcase to match your existing dana 60.

If your truck is a crewcab, you have enough wheelbase to run a divorced 205 behind the 2ndgen dodge tcase.
 

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I have heard a lot about chevy truck frames can't handle the torque a Cummins produces. You will need to box in the frame.
 

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Chevy 1ton frames are as beefy as 91-93 dodge diesels. Both have 2ndgen dodges beat.
 

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Discussion Starter · #11 ·
This is what its going in. Its currently being shipped from Washington to my home in Georgia. It is a stock 1978 K30 custom deluxe but had a 396 put in it (it gets 5 miles a gallon which is a big reason I'm swapping). I don't have too much of the technical stuff on it as I can't go outside and look at it yet. As far as the transfer case on it I'd have to wait and see till it gets here. If need be I might snatch the case and or axles from a dodge to put it in or might get a custom made driveshaft to hook up. I think the Frame will hold up but I will most likely have to make a new tranny cross member and maybe I can run some steel bars across to stiffen it up but we will see. I'm going to go and just pluck the cab right off when I can because I plan on taking it to the paint shop because there is some rust I need to address in the bed and fender wells. I have the tools and materials to pretty much fabricate anything I need for this project so I think I'm good there.
 

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Judging by the full-time hubs, it's a np203 tcase in there.

Shopping for all the stuff to get a nv4500 and matching np205 together for a cummins - on a budget - is getting to be a challenge these days.
 

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I have heard a lot about chevy truck frames can't handle the torque a Cummins produces. You will need to box in the frame.
K30s have a significantly beefier frame... k10s/k20s use the same weak frame that alwas cracks behind the steering box....
 

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I personally wouldn’t swap to a dodge front axle, that would be a down grade from that kingpin 60.
Adapter may be expensive but so is replacing worn out dodge junk (ball joints/unit bearings).
 

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Discussion Starter · #15 ·
I was also wondering if you guys think it would be a good idea to use a gas tank/fuel pump combo from a salvage truck or would I gain anything from just buying a new pump with certain specs? The truck has the dual tanks with the manual selector but I’d be happy with a single 30 gallon tank just don’t know anything about the fuel pumps for diesels I’m used to just bolting on a push rod fuel pump on a block lol.
 

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The 96 12v has a lift pump on the side of the block, no need for a electric one.
 

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Side note where in GA has 12v long blocks for 400? Ya know just curious 😁
 

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The stock saddle tanks shouldn't be a problem.

A blazer tank does fit ok under the back end. 25 or 31 gal if I recall. You have to relocate one shock.

Edit: dodge midship tank will likely not fit because Chevy frame is 4" narrower.
 

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Discussion Starter · #19 ·
Side note where in GA has 12v long blocks for 400? Ya know just curious 😁
Lol it’s not in GA I live on the ga/fl border and in Jacksonville they have a junkyard called ace pick a part and a diesel long block is 350$ with 75$ core but occasionally you can catch some sales they do like 50% off everything in the yard. Only downside is you have to pull it from the car yourself and the 5.9s go pretty quick so you have to be active when they end up in the yard.
 

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Yea they don’t actually hit the yards around us. Employees get those if they ever come in which is rare in itself.
 
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