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Hello, I have a 1970 f-250 4x4. It currently has the stock powertrain/drivetrain (FE390,np435 tranny, dana 24 t-case, and dana60 rear and 44 in front). I have not yet spent any money but I want to do a 5.9 12 valve cummins swap. Ive been looking for a 12v with the p-pump and im just wondering what else I may need. my current thoughts are the cummins with a nv4500 or zf5 tranny with a np205 divorced t-case. Id like to do this in a budget friendly manner. what do ya'll think? is there a way to do this or something similar without totally breaking the bank? Thanks for the help
 

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Also, i realize this is mostly a 4bt forum so if there is another forum i should be in feel free to point me in the right direction!
 

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WELL Welcome aboard . Several of the other guys will have better Ideal than myself .
But at 72 years old & In the parts business all my life.
& I'VE HAVE SEVERAL DIESEL TRUCKS . 3 NOW.
... so mY 1ST QUESTION IS what do you want to do with the truck . Placing the 5.9 12V in front of the NP435 WOULD BE MUCH CHEAPER. I'm even going to say 50% cheaper . But if your dreams for your truck is dreams that will require the 5 speeds then . Budget just doubled.
... I'm going to say the NP435 Is strong enough to handle your 5.9 You just can't drive 85mph.
Your name doesn't give us a clur where your from.
YOU CAN BUY lots of 5.9 91trucks for 2500.00 to 10000. of course a 10K truck is a nice one .
I just gave 600$ for the last one I bought but that doesn't happen often.

.. Budgets can you do the work yourself .. If so I'll say you can knock 3/4's of the cost down.
Hope this helps.
 

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WELL Welcome aboard . Several of the other guys will have better Ideal than myself .
But at 72 years old & In the parts business all my life.
& I'VE HAVE SEVERAL DIESEL TRUCKS . 3 NOW.
... so mY 1ST QUESTION IS what do you want to do with the truck . Placing the 5.9 12V in front of the NP435 WOULD BE MUCH CHEAPER. I'm even going to say 50% cheaper . But if your dreams for your truck is dreams that will require the 5 speeds then . Budget just doubled.
... I'm going to say the NP435 Is strong enough to handle your 5.9 You just can't drive 85mph.
Your name doesn't give us a clur where your from.
YOU CAN BUY lots of 5.9 91trucks for 2500.00 to 10000. of course a 10K truck is a nice one .
I just gave 600$ for the last one I bought but that doesn't happen often.

.. Budgets can you do the work yourself .. If so I'll say you can knock 3/4's of the cost down.
Hope this helps.
 

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Thanks for the response. I am in western Idaho so im not sure yet how the availability compares to other places. My transmission works pretty well, however I would like better "cruising" speed and i have been wanting to have a 5 speed for a while now as well as a smoother transmission. I dont plan to tow a lot but I definitely will from time to time. As far as doing the work myself... I can do most of it myself. Im 19 so I dont have a ton of experience but i know people who can help so fortunately that part of the budget will not be too bad.
 

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After getting the 4BT to work in my '68 I'm thinking that your easiest and most cost effective route would be to swap the cab/bed to a Dodge chassis.
My reasoning goes as follows your D-44 is really not up to the task at hand, I'm still running the 44 under mine but I at this point in life do not romp it on trails, now as a younger man the 44 would have not lasted so save yourself the hassles of recovery and repair and start with a 60 front. IIRC the 6 will fit in a Bump 4x4 but there are either mods to do to the firewall, oil pan or crossmember to do a plus for the Bump is the engine bay is tall and with a B series that helps. The divorced T case does help as you will be running a 2x4 trans you also have wiggle room fore and aft for the engine/trans combo, I was able to fit the ZF5 and still had room for a 203 range box mated to the front of the 205.
One other thing is you might have some conflict with the bellhousing/trans and firewall/tunnel area I', not sure as my cab is a crewcab from a F-600 and they differ a little there from the pickups. So anyway look into that option before you commit to the engine swap...Research is your FRIEND and you will be repaid tenfold in the end for every hour you spend doing so.
Welcome Aboard and GOOD LUCK.
 
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You will probably need to change axle ratios so you cruise at 1700 to 2000 RPM for best economy, which adds to the cost. Definitely will need an OD trans., although a direct NP-540 series would work with the divorced transfer case. Steve’s idea of a Dodge running gear might work well for you, lots of changing a lot of things with stock Ford running gear. I have a Dodge frame and running gear I am saving for something like that.

Ed in cO.
 

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Get the whole drive train- skip the 4 speed, 5 speed is a must. 6 speed is much better. I'd recommend getting a drivetrain you can test and drive. Even rebuilding can not turn out perfect.. The on line support is not guaranteed, search, search, search! I have a 4bt with an early GM nv4500 and wish I had a tighter gear pattern. I am working on a 24valve powered 2006 f250 with the G56. I prefer the 6 speed hands down. I am dealing with issues on my rebuild..I have 10k plus into the truck minus purchase price of truck, not all is swap related. I spent very little on parts that were adapter related, it adds up fast. Don't be optimistic, figure worse case and add some..
 

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I do agree that using the Dodge frame & DROPPING A DIFFERENT BODY onto you frame should help with lots of issues.
 

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I do agree that using the Dodge frame & DROPPING A DIFFERENT BODY onto you frame should help with lots of issues.
Doesn't this mean I'd have to find the exact right wheelbase dodge, or am i gonna have to cut up the frame?
 

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Well I'm not totally sure of that answer .
But I have the same problem . I have a D250 3/4 TON 2 DOOR TRUCK That I plan to put another old truck body also.
I believe I'll need to RELOCATE the body mounts . & That's my plan at this time . But I'm thinking the Frame mounts may need to be enlarged or lengthened .. & OR THE SAME for the body mounts may need to be reworked to make fit.
& It seems I may need to remove the dodge body mounts & Incorporate then into or onto the Donor body.. I believe that might make for a better fit. & a more quality fit .
.... BUT I'VE NOT DONE ANY OF THIS IN MY SHOP.
 

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Doesn't this mean I'd have to find the exact right wheelbase dodge, or am i gonna have to cut up the frame?
Your F-250 should be 131" WB so I'd guess it's gonna be shorter than your donor, so if you plan to use the factory bed the answer is YES.
Now without having a dodge frame here this is just a basic plan but I would want to shorten the frame somewhere between the trans/T case mount crossmember and the rear spring front mount crossmember, the cut and weld operation for the frame is pretty straight forward and you can find info to do it right easily enough.
At that point relocating or remaking cab and bed mounts should be fairly easy, I'd probably try to position everything so I could roll the frame under it for mockup as the Bumps frame is likely narrower than the dodges so you are gonna find some conflicts to iron out depending on how closely you want cab/bad and frame to sit.
This may sound like a LOT of work but in the big picture it's not really any more of a job than adapting drive train to the existing truck...$.02
 

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The thing would be which Dodge frame you used. The Cummins Dodge up to 1994 was 131" wheel base which would be exactly the same as the Ford. 1994 up was 135" wheel base. Of course the P pump came in the '94-98. There were other changes. The early trucks had passenger's side drop for the transfer case and later ones were driver's side like the Ford. Don't know your performance plans but nothing wrong with the VE pump engine in the '88-93. The '91.5-93 intercooled engine would probably be better. Either would probably benefit by having a better turbo like the P pump.
 

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The thing would be which Dodge frame you used. The Cummins Dodge up to 1994 was 131" wheel base which would be exactly the same as the Ford. 1994 up was 135" wheel base. Of course the P pump came in the '94-98. There were other changes. The early trucks had passenger's side drop for the transfer case and later ones were driver's side like the Ford. Don't know your performance plans but nothing wrong with the VE pump engine in the '88-93. The '91.5-93 intercooled engine would probably be better. Either would probably benefit by having a better turbo like the P pump.
A 131" Dodge frame existing makes the frame swap a very desirable option in cost and would leave funds and time to do all the suspension soft parts giving you a zero time running gear.
 

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The Dodge frame and running gear I am saving has a wheelbase of 154”, so it must have been a double cab. I never saw the body.

Ed in CO.
 

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Ed your 154" is from the '94-02 series trucks. That one was either the club cab with long bed or quad cab with short bed. Actual measurement is 154.7". The 131" was only on the regular cab with 8' bed up thru 1993. During those years there were 5 different wheelbases 115", 131", 133", 148", and 165". After that they scaled it back to just 3 sizes.
 

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Based on the extensive set of pics that I used to have of a '72 F-250 with a 6BT in it the firewall to engine clearance is a problem. On that truck he cut the firewall and then added sheet metal back to close the hole. In the process he lost the windshield wiper linkage to his cut. He built it as a hot rod. I needed something that I could drive in any weather from the Lower Left Coast to Spokane, Glacier NP, or Utah and back. I passed on it & bought a CTD.

Was it me, '94-up Dodge donor chassis, put the Ford sheet metal on the coil sprung front axle chassis. To roughly the trans to t/c adapter it is a boxed frame, so it will be stiffer in the engine bay. I would not box the rest of the frame, run it as-is. By just moving the spring hangers I could shorten our '96 ClubCab LB's WB by at least 6" Doing so would require re-arranging a couple bits like bed mounts, but those aren't likely to work for a Ford bed anyway. Finding one of those trucks as a donor gets you the desired P-pump, a D70 rear axle and a D60 front axle. the first step in considering such a swap would be where is the front axle center-line relative to the firewall at the chassis center-line for both the Ford sheet metal and the Dodge chassis, and the related next step is where is the radiator for both relative to the front axle center-line?
 

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Interesting variation in points of view in this thread.

My favorite recipe for a 67-79 Highboy Ford is to use the intercooler, radiator, shroud, plumbing and engine from a 91.5 to 93 Dodge. For the transmission I prefer the getrag G360 or the NV4500 mated to a Ford NP205 or a Dodge NP241. You could use a ZF, but the 7.3 and 460 bellhousing get into the firewall real bad. I have a Triton pattern ZF5 and NP205 behind the 12 valve in my highboy.

Using a mated transfer case will require a swap to a high pinion type front axle, but the swap is worth it.

I use Superduty leaf springs for a Diesel application. They bolt in with very minor modification.

I use the Superduty PS box as well.

Swapping bodies is usually quite the undertaking. Anyone suggesting that because the wheelbase is similar it will be a good route to go has never actually done it. The critical aspect is the geometric relationship between the firewall, front axle and engine. The wheelbase would be cake to change compared to changing all of the above.

The Highboy chassis is quite a bit better than most Dodge stuff. You have to go to the 2014 and newer Dodge chassis to get something as strong or as good of handling as the old Highboy setup was/is. Even then though, The Dodge AAM front axles leave some serious problem areas to frustrate you. AAM knuckle/balljoint interface is a joke. Tons of problems related to AAM balljoint issues. Very flawed design that can haunt you.

I am of the opinion that a 78-79 F-250 HP44 is a reasonable axle to use under a highboy with a 12 valve. They aren't weak. The balljoints hold up fine. I have done it and had zero issues with the 44 front. If you had the light duty closed knuckle 44 front that most highboys came with then that axle is junk, you should upgrade regardless.

I have done this swap many times. There is no reason at all to cut the firewall. People usually get frustrated when they try to stuff a giant intercooler into an early Ford. My suggestion is just don't. The first gen one will cool 300ish HP towing moderately on a pretty hot day with the stock mechanical fan. If you think you need twins and 600HP you will need some fancy fab skills to fit it all and make it look decent and actually work.

EDIT: Just wanted to add I used 35" MT tires with that HP44 front axle and 4" Superduty springs under a 12 valve. I put 65k miles on that truck before selling it. I used 4x4 often, but didn't hammer down on it or anything. Spinning the tires in 4lo climbing rutted out old logging roads probably the harshest use it saw with me.
 

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If your not going for big power numbers the ve pump engines start nicer and are better for cruising, I used a zf5 in my swap as I needed an adapter and all the manual parts for my 4bt anyways, it still came out to the the same price or cheaper than what some of the nv4500 are going for. I’d avoid the frame swap unless you can easily title it in that state, the ford legal vin is on the pass side frame rail and the door tag is just for warranty, with out the ford frame you don’t have a truck, also many of the manufacturers started to move the fire walls back so even though the wheel base is the same, the distance to the fire wall still might be off.
 
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