1952 Dodge B3b 1/2 Ton, Cummins Diesel

[1952B3b23]

Hey Guys,

I just joined the forum not long ago but ive been working on this project for a little over a year now. The truck is a '52 Dodge B3b, part of the pilothouse series of trucks. I bought the truck in running and driving condition but as you can see from the pictures it was missing lots of original equipment. The plan when i bought the truck was to find a bed for it and remove the ugly wood flat bed. Then just cruise around in it for awhile. So i went ahead and bought a bed and then completely changed my mind on what i wanted to do. This is where my love for Cummins diesels comes in... i got to thinking that the truck would be pretty sick with a Cummins 4bt. That got the ball rolling and off i went researching "4bt" swaps. I found tons of info on them, and a whole forum devoted to those kinds of swaps. So i decided to commit and bought a 1993 4bt (VE Pump) out of an Oshkosh truck with a Borg-Warner T19 transmission (4 speed). The motor ran well when i went to see it and the owner claimed it had about 180k miles on it. Well that was one piece of the puzzle that was missing next i bought a mopar 8 3/4 rear end with the 742 case and posi. I figure that if that would hold up to the big muscle cars of the day it should do alright behind my 4bt. For a transmission im not going to use the T19, i have a Getrag G360 out of a '92 12 valve dodge cummins that i got for free. That tranny is a 5 speed with OD so it will give me decent cruising combined with the 3.55's in the 8-3/4. My reasoning for going diesel is because i love the Cummins motors and i think it will make for a unique truck and fun to drive with all the low end torque.

The Plan:

I plan to use the original frame and strengthen it as needed to handle the weight, vibration, and torque of the motor. These 4bts are pretty heavy (750 lbs dry). Then again when you compare that to a big V8 gasser the weight difference isnt all that much. The original flathead 6 and three on the tree tranny weighed in at a combined weight of about 750 lbs. I figure with fluids and the Getrag attached the weight will be at about 1000 lbs.

The front suspension will be the stock setup except ill be replace/rebuilding its components. New tie rod end, king pins, drag link, etc. A very important mod will be getting rid of the drum brakes up front and going to discs. The steering will remain as the original cross steering setup with manual Gemmer steering box.

Rear suspension will be the leaf spring setup with the mopar 8-3/4 rear end. That has updated drums which combined with the discs up front should give good stopping power.

This truck isnt going to be a rat rod per say, more like a mild custom. Im building it for me so i can have a cool ride thats different and fun to cruise around in. I hope you guys like it.

I know this is a pretty long post but it basically sums up what ive had rolling around in my brain for the past year or so.

Thanks for looking and questions/ comments are welcome,

-Chris

[1952B3b23]

Here are a few pictures of the 4bt.

EDIT: I dont know why all the pictures posted sideways...thats not how they where taken.

-Chris

[1952B3b23]

So in order for the frame to better handle the weight, torque, and vibration of the motor ive decided to box it in with 1/8" plate. The boxing plates will extend about a foot maybe more underneath the cab. The motor mounts will get welded to them as well as the transmission crossmember. I wanted to add enough boxing plate so that it stiffens up the frame but not so much that it takes all the flex out of the frame.

This is something that ive discussed with a few different people and they seem to think that to much boxing will eliminate a lot of the flex the frame was designed to have. I seem to think that its still going to have flex because of the fact the the motor and its power output is quite a bit more than what the original frame was designed for. What do you guys think?

I can always add more boxing plates now since im in the middle of doing it anyway. The attached pictures are of the passengers side frame rail boxing plate. I made a cut out in it so that i can get at the shackle mount that sits in the frame so it can easily be replaced.

Thanks for looking,

-Chris

[junker39]

Sounds like a good idea about the boxing. Of course I really don't know anything about why the frame would need to flex anyway. The diesel will surprise a lot of folks. And it'll be good to pull a trailer with. Lookin' good. Keep on truckin and post more pics when you get 'em.

[Dirtyrat]

That is going to be an awesome truck, I looked for a while for 4bt and 6bt and I just couldn't find one before going with the 5.4 I'm using now.

I can't wait to see more on this build!

[mikec4193]

HI 1952b3

Love love love Dodge Pilothouse trucks...that diesel engine is only gonna make it better. way better on fuel cunsumption than the stock flat head 6 was...

thanks for bringing us along for the ride....love those pictures...

MikeC

[1952B3b23]

Originally Posted by junker39

Sounds like a good idea about the boxing. Of course I really don't know anything about why the frame would need to flex anyway. The diesel will surprise a lot of folks. And it'll be good to pull a trailer with. Lookin' good. Keep on truckin and post more pics when you get 'em.

Well the whole frame flex issue is something that i dont completely understand myself. Basically i was told that the frame was designed to flex a little bit to better deal with the road conditions of the days, and to much boxing could eliminate the "controlled flex" and cause poor handling and other problems. Now i dont know how much of this is true or really matters since my truck will only see paved roads. I also keep going back to the fact that they designed these frames around a flathead 6 power plant, about 90 HP and 175 ft-lb is what my truck came with. This truck is going to have quite a bit more power than that so in my opinion the frame is still going to flex even with the boxing. Any one have any thoughts on this?

Yea the diesel will definitely make the truck stand out. Combine that with the fact that its a pilothouse and shes going to be pretty bad a**!

Thanks for the comment,

-Chris

[1952B3b23]

Originally Posted by Dirtyrat

That is going to be an awesome truck, I looked for a while for 4bt and 6bt and I just couldn't find one before going with the 5.4 I'm using now.

I can't wait to see more on this build!

I searched for quite awhile for my 4bt and finally found one about 1.5 hours from my house. Of course after i bought it an add comes up on Craigslist about another guy having 100 of them to sell about the same distance from me. I think i got a good deal though cause i can sell off the T19 tranny that i dont need and make some money back. 6bt's are easier to find than the 4bt's and less expensive, i actually find quite a few of them for sale up here in the north east.

Thanks for the post,

-Chris

[1952B3b23]

Originally Posted by mikec4193

HI 1952b3

Love love love Dodge Pilothouse trucks...that diesel engine is only gonna make it better. way better on fuel cunsumption than the stock flat head 6 was...

thanks for bringing us along for the ride....love those pictures...

MikeC

Thank you Mike. The 4bt will give much better fuel economy than the flatty, i should be able to get in the 20's for MPGs around town. That is if i can keep my foot out of the throttle I do plan to do some power mods to the motor to make it a bit more fun to drive.

Stay tuned for more updates and pics,

-Chris

[maverickmk]

That's not a rat rod, that's a sweet ride that's getting better by the day. I'm along for the ride. Love the diesel idea. Someday I want to do a diesel swap as well.