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Discussion Starter · #1 ·
I have a1973 Dodge W200 that I want to stab a 4bt in. Currently it has a 360 backed by a Np435 with a divorced 205 (this is factory setup). The Np435 is sorta the grandpa to the Nv4500. I like my transmission so I would like to keep it. My question is: Can I find a bell housing that would allow me to bolt the two together?
 

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Yes, but you might want to think on that. The NP435 was a great transmission but lacks an OD gear and like the NV4500 doesn't have ideal gear ratios for a 4bt. The 4bt likes to operate in the 1700-2000 RPM range for best torque and fuel economy. It can rev higher but most engines have a 2500 RPM governor limit. You can increase that number but the fuel economy will take a tumble big time. As far as adapting the NP435 to a 4bt, there are several possible ways. You could use the transmission as is with the 360 bellhousing and use a SAE3 engine adapter, flywheel, clutch, and starter. To join them you'd need an adapter from Phoenix Casting and Machining. Another option might be to change the bellhousing on the transmission to one like came on the NV4500 and use standard Dodge 6bt adapter parts on the engine. You'd have to match the clutch disc to your input shaft since the Cummins ones were different. If the engine you find happens to have a Ford or GM adapter plate and flywheel it might be easier to source a Ford or Chevy NV4500 since you are running divorced. Must keep in mind you max top road speed will be in the 50-55 MPH range and very poor fuel economy which usually isn't very desirable. You'll probably find a change in transmission will be desirable.
 

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Certainly, most end up wanting an overdrive. But, it would be good to know the OPs differential gear ratio, tire size, and how he plans to use the truck.
 

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For instance, I had a 1989 D250 with the 6BT and the 3-speed AT. That truck was 100% stock...and, considering my use, and my preferences, it was great.
 

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Discussion Starter · #6 ·
Thank you for your great information. I knew that diesels like low rpm, but I just didn't think of it. I'll suck up the extra price and get a Nv4500. I plan on making this into a off-road recovery rig with a boom. So on the trail the granny gear and the diesel would be awesome, but I need to first get to the trail and that combo would not be fun.
 

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What front and rear axle do you have?

If you don't have the 4BT already, you might at least give some thought to a 6BT. Considering you are putting it in a 3/4-ton truck. Around here, the 6BT are way cheaper, and easier to find, than the 4BT.
 

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I Have a 1972 BRONCO . I'D SWAPPED the 3 speed out & REPLACED it with the NP435 WHILE I had the V8 gas still in it . But I could not keep It from getting hot . SO I DECIDED to swap to the 4BT Cummins . & I had lots of diesel help as I worked at the Dodge Dealership at this time . We were the biggest diesel dealer in TEXAS. & I was one of the service advisors .. Tough Job. I use my Bronco mostly on my farm checking cows & Hunting .
I love my 4BT & MY NP435 great low gear ..
...But CHAR is correct .. I have 3:55 & 285R16's & 55 IS ABOUT MY TOP SPEED ...
.... I THINK MOST OF MY MILEAGE IS ABOUT 16 mpg..
Best I've every gotten was in a Car Show Cruise & I got 24 mpg.
But I was driving mostly about 25 mph..
SO AN Overdrive sure would be nice.
 

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I have done almost the very same swap in my old Power Wagon , I used Phoenix Adapter to SAE 3 and the NP 435 to a married NP 205 case , it has locked Dana 60 front and rear geared at 3.55 . This was a great trail to see if I could do the swap . I looked for 4 years to find a gasser Dodge with an NV4500 . When swapping to NV4500 , you will hydraulic pedal and every piece of hardware to make it operate correctly . The hydraulic “ linkage “ is a bolt in swap to your truck , but again you must find every piece of OEM hardware , this is going to be tough , I think . It was for me anyway . I bought the complete running truck , just for this reason . Also this is a big issue that will need to be completed to install hydraulic “ linkage “ , the main fire wall electronic connector will need to be moved about 1 1/2 inches closer to the drivers fender to clear the hydraulic MC . As stated you use any brand trans from a 4x2 because of the divorced case . PM me if you have any questions , I try my best to answer them and help you out .

The swap is well worth the effort , I’m rocking 100K on mine , and haven’t looked back yet . By the way ,in its current state of tune , it will do 27-28 mpg anyway of the week , using 4x4 will knock this in the head also .
Tire Wheel Vehicle Automotive parking light Automotive tire
 

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DR DAVE ...Now that is a cool looking old ride.
... Guys I'M GOING out on limb & saying you can't believe all the crazy things you can with an Old Truck like Dave & Mine .
I'm a farmer ... So when my grand sons were young I did crazy stuff Just to show the kids how to think outside the box.
I used mine to drag an old horse drawn tandem to plant a deer woods food plot. It was about 7ft wide. I put a hand throttle mounted on my shifter . I'm rocking along with radio.. p/s .. Bucket seats .. fans to move air .. Ice chest with cold water .& Beer for me in my floor board .
Later we put on a grain drill on behind & it's 12ft wide . Planted the deer crops .
I've pulled very large trees cut down to the brush pile .
... & I moved a building with mine . This storage building I jacked up & put on skids . It was 16 ft by 8ft.
Now I put a receiver hitch on my front bumper .. & I did bend my front bumper .. But the drive train pulled the load .
... I've drug Fertilizer distributors with mine . I mounted a 12ft deer stand in the bed of mine & Drove to a Center Pivot IRRIGATION UNIT . iT HAD A ROAD TO THE CENTER Covered up with about 8 ft tall blood weeds. But the road to the center of Pivot had been used all summer . SO Me & a grand son drove to the center of the pivot in my Camo covered Bronco .. with a 12ft deer stand mounted in the back of my Half cab. we crawled up into the stand . & I don't believe that Diesel scared any deer from that field .

... I'M Sure Dave's truck Might even be a notch more capable than my Bronco . Because my Dana 20
is said to be our weak link.
...... But go far it Dodger . you'll not be disappointed .
........................& It's so cool th=o have the only one in town .
 

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I ran a getrag and a brownie(2:1/1:1/.75) with 4.11 diff in a Dodge D200. Double OD was nice for hiway but the lo was handy as well. Without brownie 3.54s are ok unless you can get the 1st gen 3.07s. In the west the speed limits are higher. What flywheel housing adapter you have would also make a difference. If the ford adapter, I would use the small block zf5 2wd to your 205. Easiest/cheapest and OD. Eggman ran a M5R2 and abused the holy chit out of it. Getrags have a bad rep behind 6bts because guys turned up power and expected them to survive past their specs. Ive used G360s behind turned up 4bts(160-200hp) and have had no issues at all. Also simple/cheap and easy.
 

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I'm still running a M5R2. Replaced a couple of leaky hydraulic clutch slave cylinders - the transmission has tocome out.
 
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