The 1947 - Present Chevrolet & GMC Truck Message Board Network - New guy here looking to do a Cummins swap

The 1947 - Present Chevrolet & GMC Truck Message Board Network (https://67-72chevytrucks.com/vboard/index.php)

- Diesel Conversions (https://67-72chevytrucks.com/vboard/forumdisplay.php?f=240)

- - New guy here looking to do a Cummins swap (https://67-72chevytrucks.com/vboard/showthread.php?t=624487)

New guy here looking to do a Cummins swap

Re: New guy here looking to do a Cummins swap

MHoward3 - Thanks for posting this. Could you give a few more details about your truck? What you expect to do with it? Automatic or manual? 2wd or 4wd? etc.......

I'm sure with some more information you will get more replies.

Re: New guy here looking to do a Cummins swap

Quote:

Originally Posted by COS399 (Post 6623438)

Sure thing.

It's a 79 GMC k15 shortbed 4x4

It will just be a truck to tool around in. No crazy loads, maybe pull my boat here and there. But mostly just a pavement pounder that's capable of commuting to and from town and the occasional camping trip etc.

Putting either a 4" and 33's or a 6" and 35's I'm not really sure yet. Trying to figure out what I'm going to do for a motor right now.

I'm not looking for extreme power or anything at this point, being that this is my first real build and it's more a learning project than anything. I would like to keep it as simple as possible. I've heard 12 valves are easier swaps with less wiring?

I don't really care auto or manual either way, whatever is more 'practical'.

As I said, I'm just trying to gather some info outside of the build threads I'm researching on.

Thanks for your response by the way!

Re: New guy here looking to do a Cummins swap

I don't know anything about diesels, but welcome to the forum.

Re: New guy here looking to do a Cummins swap

Quote:

Originally Posted by mhoward3 (Post 6622031)

Hey guys. I'm new here and new to diesels. To be honest, I'm pretty ameture to restorations in general.

I bought a 79 GMC a while ago just as a learning project. I've always wanted to restore one of these old trucks.

I would love to swap for a Cummins but I have some noob questions.

My budget for the swap is 10k. I would like to keep costs as low as possible. Because as I said...its no show truck. Is this achievable with my budget?

can you do it for 10k? you could most likey get an engine it the frame and make the truck run for that price. it doesnt leave a lot of room for any upgrades or rebuilding though. you would have to find a known good pull out driveline that you could run as is. that would probably eat 4k. then you will have the cost of wiring and driveline mods. i would also save some of the budget for axle upgrades. a cummins will eat a 12 bolt and d44 alive. figure 800-1200 for a set of axles that you can drop in and run

For a beginner is a 12 valve swap easier, cheaper? I'm not sure on the difference here.

as far as making an engine fit in the truck, one really isnt better or worse than the others. for cost of the engine i would stay away from the CR models. they will also be the most difficult as far as electronic peripherals that you need to deal with. a first gen 12v will be easy to hook up and make run in the truck. not to mention if you get the pull out driveline, the transfer case will work with your GM axles. if you get a second gen 12v driveline the transfer case will be on the wrong side.

Do guys swap these on 1/2 tons? Will my frame need to be beefed up? I saw a thread on here where the guy boxed his frame with steel. Is this necessary?

necessary? no. better, IMO yes. there have been plenty of 1/2 ton trucks converted to a cummins. there are some weak points in those frames up by the steering box that will need to be addressed especially with the added weight though.

When looking for a used motor, what are some key points I should be looking for? Does the year matter?

first gen trucks come with the ve pump and were in dodges 89-93. the second gen 12v is in 94-early98 and have the inline p7100 pump. sounds like either would be fine for you in stock form.

I've done a lot of searching but still have questions.

Thank you!

answers in red

Re: New guy here looking to do a Cummins swap

I had never done any kind of diesel swap before but mine went fine . Lots and lots of good peole on here who can help you along . Ryanroo and Deisel wrencher have been the most helpfull. They love boxing frames too !!!

My advice would be to get a 1st gen dodge with a crummy body and take all the driveline . thats what I did . Re used so much of that truck . Good luck and post a pic or two of your truck when you have a moment . Ryan did a burb a while back check thread in here called v rig . It will be rite up your alley