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Your cheapest option might be finding a cheap rusty 89 - 93 Dodge 4WD with the 5 speed. You pretty much end up with all the parts you need for the conversion.
 

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cj10a tug
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Discussion Starter · #4 ·
Your cheapest option might be finding a cheap rusty 89 - 93 Dodge 4WD with the 5 speed. You pretty much end up with all the parts you need for the conversion.
Hi, my first option would be to find a complete 12v rolling chassis & leave it but thats like digging for gold . another option to find a 4bt build & put my body on it , The 73 chassis is free so thats why i thought to pull the gas engine & go with the 4bt or 12v if they make a bolt up deal . Can you explain in more detail your thoughts thxs steve cj10a
 

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cj10a tug
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Discussion Starter · #5 ·
What trans. do you plan on using? An OD trans. Would be desirable, then look for that adapter. A 435 is direct, not very useful. 540 series are closer ratios; rare with OD, delete 3rd gear,though.
Ed in CO
HI. yah if i use the 73 chassis i really would like to leave it Manual trans , just pull the gas engine & mount a 4bt or 12v if they make an adapter plate for either ??? and if so your opinion on both set ups ??? fabricating the motor mounts is the easy part for me even though id rather find a roller with a 4bt or 12v already done, but the 73 chassis is free Your thoughts please Thxs steve cj10a jeep tug build
 

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Hi, my first option would be to find a complete 12v rolling chassis & leave it but thats like digging for gold . another option to find a 4bt build & put my body on it , The 73 chassis is free so thats why i thought to pull the gas engine & go with the 4bt or 12v if they make a bolt up deal . Can you explain in more detail your thoughts thxs steve cj10a
I do not know of any bolt up adapter for your application. This does not mean that there is not one out there. The down side is even if there is one you will be limited by your gear ratios in your differentials because your transmission has no overdrive. There were diff's out there that came with the 3.07 ratio that fit your application. Finding a set of those these days is even more difficult than finding a rusty first generation Dodge for parts. Those axles were used behind the Dodge Cummins set up with the factory Dodge 727 non-overdrive transmission. I believe they were only used for the 1989 thru early 1990 model years.
 
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You need to first figure out what you have. What gear ratio differential and transmission does the '73 have? You ask about an adapter kit and no such thing exists that I know of. However, you could possibly bolt up the 4bt to your stock drive train. Phoenix Casting and Machining Inc. has adapters for various transmissions to an SAE engine housing. An SAE3 would be a very common setup on a Cummins B series engine. You'd have to work out your own engine mounting to the truck chassis. SAE systems normally had a 3 point mounting system. 2 mounts on the flywheel housing and one center mount at the front of the engine. See photos below. If you did all this you have the issue that you top speed will likely be 50-55 MPH or less. The 4bt likes to run in the 1700-2000 RPM range. Can go faster but fuel mileage takes a dive above 2000 RPM and so does engine torque. Like BobS mentioned, the 3.07 gear setup in the early Dodge Cummins solved that issue with the TF727. Don't know what gears are available for your axles but the stock ones probably won't make you very happy.
 

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I have 79 Power Wagon ,4BT , Hx30W , Nv4500 ,Np205 , Dana 60 ,3.54 Ratio Power Lock both front and rear , 20,000 hydraulic winch . Hydra Boost brakes , it will absolutely go anywhere you point it , any weather and do it getting 30 mpg all day long . View attachment 134890
That's a nice rig! I love the 72-80 dodge trucks. Is that a dana 60 front as well or an 8 lug 44? What tire size are you running?
 

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Sorry forgot to add PM me questions , I’ll help you anyway , that I possibly can . Ex Forestry Rig . 60 series axle front and rear . 265/75-16 tire size . RPM is 2000 at 65 MPH . The OD is a must . Your 73 rig should be divorced transfer case . Much easier to do engine trans swap over married case swap. 4 or 6 BT with early 518 (?) should be very easily completed almost a bolt in operation .
 
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