Hey guys, been a while since I've been on what with the holidays and work being crazy. Hope all has been well. Recently picked up a project truck and been doing some digging with little resolve. Most everything I'm seeing is for 4x4 swaps. Here goes, i picked up a very nice 87 d150 and I'm wanting to do a Cummins swap into the truck. Ive got the motor/trans, wiring, gauss, everything. Several parts trucks to source from. I'm wanting to build a very detuned truck. 12 valve, auto with stock 1/2 ton rear end. I'm looking for great mpg. That's all. I just want it to go 70mph down the highway and get great mileage. My question is ive seen a few posts about swapping 3/4 ton diesel coils up front and just going on down the road. Is this accurate? What would ball joint life be like. Would the 1/2 ton rear end hold up to the torque very long. Thanks guys.

 

About the only thing I can answer from my swap is the rear axle. Which rear does your truck have? My 03 has a 9 1/4" 3.55 LS rear and it's held up fine for 6 months. I know guys running compound pee pump motors on this rear axle with no worries. Mild HP and being an auto makes it a little less harsh on driveline parts. Just build an axle wrap bar to keep the twist under control.

 

You can swap springs however, I would thing the control arm bushings, ball joints, and small brakes wouldn't like it very much. Personaly, I would swap both front and rear over to 3/4 ton, keep the 1/2 ton springs in the rear and find the highest gear available for that rear axle. Benifits of bigger brakes and peace of mind on not beating the snot out of the 1/2 running gear.

 

Ive been thinking the same thing about swapping everything over from the 3/4 ton. I have a donor truck that would work well but i was really hoping to just stuff the 12 valve in and go. I don't want the 8 lug wheels. The weight difference from the 318 to the 360 is roughly 400lbs. It's alot more weight i know. I've been researching swapping a 4bt in as well but don't think I'm going to go that route due to the efficiency of the 4bt not being all i want it to be. Not to mention how rattley the little things are

 

+1 to this

 

The nice thing about going with 8-lug is you can run a tall, skinny tire with less rolling resistance than you can by being limited with the 5-lug wheels and not worry about over working your brakes. If I remember right, there was a reason they didn't build many 1/2tons with the 440 due to the weight issue.
I can get wanting to just drop it in and go, but I think you'll be kicking yourself later down the road. Just my .02..

 

Its seems most of the 6cyl & 318 2wd trucks got the 8.25" rear axle.

Cummins coils are about 2" too long for the half ton arms.

D250 cummins trucks have a dropped steering link to clear the oil pan.

I used a '90 D250 donor for my 2wd ramcharger. All the 8 lug gear goes in like cake.

Those 94+ half ton wheels on your truck also come in an 8-lug variety.

 

Looks like you might be able to use a Cummins coil and use a #4000 lower control arm. Some guys have used the heavy lower control arm to lower a 1/2 ton.
How to lower the front of your 1972-1993 Dodge Pickup - DodgeTalk : Dodge Car Forums, Dodge Truck Forums and Ram Forums

I would look for a Dana 60 rear, cheap insurance and should be able to find a 5 lug version.

 

That lowering trick uses a van control arm. The 4000# pickup arm won't take a light-duty balljoint. I tried that.... the hole to seat it in is way too big.

That still doesn't address the steering linkage. It's made from thicker rod, and its dipped to clear the oil pan. The steering knuckles need to be reamed out for the larger TREs.

There's nothing scary or detrimental about going 8lug. The only mod I had to do was drill out the two LCA bolt holes below the crossmember - the bolts are bigger. Everything else bolts up.

Since Dodge uses the same calipers on all 2wds, I made sure to swap over the dual-diaphragm booster from the D250.

 

here is my 1/2 ton cummins i have been daily driving it for 4 years now in the spring summer and fall in ontario all i did for springs was a set of heavy duty springs from rockauto the 1/2 ton rear end will hold up fine biggest problem is getting the u joints/ drive shaft figured out i have recently gone to a ford 8.8 under the truck and did a 3/6 drop which i cant find picture of it on my pc and truck is in storage right now if you have any question feel free to ask i try to come on the forums every couple days

 

found one

 

More than one way to skin a cat

I have aspirations of towing with mine, and a glut of 8-lug wheels. Nevermind that my cummins came with a D250 wrapped around it already. One thing on the cummins cab... the firewall/tunnel seam is trimmed back. Looks factory. As a precaution, I trimmed it back extra on my RC. I'm not at final fit stage so I don't know if it makes a difference.

What did you encounter for draglink clearance?

 

no drag link problems at all everything was pretty well a straight forward swap except had a really tiny trans tunnel do to it being a auto 2wd 1/2 ton i ended up cutting the tunnel out of the doner here are a bunch more picture of from when i did the swap https://www.dieseltruckresource.com/...ersion-303540/