1971 D200 Conversion W200

[Wellser]

Here are a couple reference pics from a 71 W100 I helped restore a few years back
383/727/205
727 had the shortest output you can get.
The intermediate driveshaft was obviously rather short but still had the proper slip yoke.
I have worked on a 65 W200 that had a 413/727 (not stock) using the stock NP201. Using this short tailshaft version 727 (usually from motorhomes) no issues were had.

I do have a NP205 with PTO, crossmember, 4x4 driveshafts (for 128" wheelbase truck), PTO driveshafts and a factory Braden LU-2 winch with brackets and bumper for sale in Northern CA if you were interested.

Thanks for this. I am interested. I sent a PM.

[Wellser]

What you need is a 69-71 W200 donor truck to get yours as close to a "bolt-in" set-up as possible. It would have everything needed. But then you may not know its condition.

Or you could get multiple pieces from various trucks.

To keep your engine/transmission you can get a divorced NP205 transfer case from a 69-74 W100/200/300 truck.
Front axle can be from 61-74 W200 if you want drum brakes, or 75-later for discs.
75-79 D44F & D60F are full time. 80-84 have selectable manual locking hubs. 85-later D44F switched to CAD, D60F did not.

Reportedly you cant use a 75-later front axle with a divorced transfer case due to improper pinion angle but many claim to have done so without any issues.

Some choose the route of finding a 4x4 chassis & swapping over their cab.

Have you considered buying a second truck (4x4) and keeping yours stock?

Bucky

Thanks for good info Bucky. I am considering keeping my truck as original as possible (with some upgrades here and there) and just picking up a W series somewhere else. Got a '69-'71 W200 in decent shape laying around you're looking to pass on?

[Wellser]

Auto trans W's were a factory option for the later swepts, so its not an aftermarket mod, but they are extremely scarce. I've owned, seen and photographed hundreds of swepts and never seen a single one with an auto. Swapping to a later chassis would totally negate any realistic similarity to "dad's truck".

Agreed on the "swapping to a later chassis" comment

[Conductorblg]

A cursory look under the '90 W200 I wrecked about 5 years ago revealed that the automatic transmission (518) and transfer case share a single wide crossmember and brackets that bolt to the underside the lower frame flanges using 4 bolts per side. While the exterior styling was changed in '81, I'm guessing the same or similar setup was used on all the trucks of the 72-93 generation that used an automatic. My wrecked '90 is/was a small block (360), but big blocks were an option into the late 70s. I swapped the Loadflite (727) behind the 383 in my '68 D200 out last year (Feb) for a RH-47 (heavy duty version of the RH46 used with the 10 cylinder and diesel engines), but bolting the transmission/transfer case setup of the '90 into the frame rails of the '68 still looks to be fairly simple, even if the crossmember needs to be spaced up or down slightly for engine angle or floor pan clearance. It is likely both existing crossmembers under the transmission will need to be removed. The crossmember tying the rear perches of the front leaf springs together looks like it will not need to be touched. In my case it was already dropped 3" to clear the overdrive transmission oil pan, but still looks like it will clear the front driveline. The matching '90 axles (Ramtrac Dana 44 and Dana 60) and drivelines look like they will work also, although it's looks I'll need to rework the exhaust headpipes. I also plan to convert the original power steering to the integral box unit and matching draglink from the '90.

The friend that built the RH47 for me says I can remove the overdrive of the RH47 and bolt on the one from the 518 without removing the transmission from the truck, simplifying the swap out. I had to use offset dowels to line up the Ultra Bell, and although the alignment should not change, it's a bit of a relief not to have to remove it. I did not get the 4-5 MPG increase in fuel economy I had hoped for, but 12 MPG is still a 20% improvement over 10. The reduction of 800 RPM at freeway speeds (2600 @ 65 to 1800 @ 70) is what really made the swap worthwhile.

[Wellser]

Doesn't the auto trans have to be shortened in order to get the transfer case behind it?

Correct. And for the record, I have an NP205 and a Dana 44 front axle for sale. I wouldn't recommend it because I just wouldn't try it. I'm with BigBlockTrucks in suggesting a later model chassis if he really wants an automatic transmission, but that's no walk in the park either.

If I use a divorced NP205 do I still need the shortened transmission?

[Wildergarten]

If I use a divorced NP205 do I still need the shortened transmission?

In principle, MAYBE not, but you might end up placing it farther back than can preserve the correct driveline angles for the jackshaft such that you would have to fabricate a custom crossmember that (hopefully) wouldn't interfere with the bed. Jackshafts go through a lot of grief because they're so short (why the industry got rid of them), making precise control of parallelism between the two yokes especially critical. That would probably mean you would also have to fabricate or modify the transmission crossmember to steepen the angle at which the engine and transmission sit.

Then you'd have to fabrciate new linkage rods and I don't really know if you can come by the bracket to support the shift lever nor whether it would still clear the transmission with the shift lever slot penetrating the transmission hump in the cab in a workable location. Even if you fabricate a shif lever bracket and pivot, you'd still need it to be long enough to provide actuation at the NP205, yet that length in the part of the lever below the cab would likely interfere with the transmission.

It's a tough problem. I wouldn't try it.

[PwrWgnDrvr]

Jackshaft is incorrect. By definition a jackshaft is something completely different - https://en.wikipedia.org/wiki/Jackshaft
The FSM refers to it as a "short couple shaft" in section 16, titled Propeller Shafts.
The parts manual refers to it as an "intermediate tube". (16-02-3)
Laymen typically refer to it as an "intermediate shaft".

[BigBlockTrucks]

My vote says it’s an intermediate shaft, but I have heard it called a jack shaft more times than not.

They used to call a donkey an @#% now they call it a donkey. Lol.

[Wellser]

If I use a divorced NP205 do I still need the shortened transmission?

In principle, MAYBE not, but you might end up placing it farther back than can preserve the correct driveline angles for the jackshaft such that you would have to fabricate a custom crossmember that (hopefully) wouldn't interfere with the bed. Jackshafts go through a lot of grief because they're so short (why the industry got rid of them), making precise control of parallelism between the two yokes especially critical. That would probably mean you would also have to fabricate or modify the transmission crossmember to steepen the angle at which the engine and transmission sit.

Then you'd have to fabrciate new linkage rods and I don't really know if you can come by the bracket to support the shift lever nor whether it would still clear the transmission with the shift lever slot penetrating the transmission hump in the cab in a workable location. Even if you fabricate a shif lever bracket and pivot, you'd still need it to be long enough to provide actuation at the NP205, yet that length in the part of the lever below the cab would likely interfere with the transmission.

It's a tough problem. I wouldn't try it.

Ok, thanks for the input. Do you think that could be overcome with a slip yoke eliminator?

[Conductorblg]

Checked with a friend that runs a small one man transmission shop yesterday. He offered up a short shaft 727 core for under a hundred bucks that would provide the all parts needed (mainly the main shaft and tail housing) to convert yours to the shorter transmission length needed to make this work. That core plus the parts offered by Powerman in an earlier post to this thread on 22 Mar 23 (NP205, transfer case crossmember, and driveshafts) gets you almost all the way there. Outside of the incidentals that always pop up, you would need to find a shifter for the transfer case and the spacer blocks (factory or aftermarket) that go between the rear end housing and the rear springs to make the truck sit level with the 4WD front axle, but if I had the core transmission and Powerman's parts in hand I wouldn't hesitate to take it on if I hadn't already converted mine (68 128" WB 383 Camper Special) to overdrive (RH47).

[Wildergarten]

Ok, thanks for the input. Do you think that could be overcome with a slip yoke eliminator?

I know absolutely nothing about such a beast.

[Wildergarten]

Jackshaft is incorrect. By definition a jackshaft is something completely different - https://en.wikipedia.org/wiki/Jackshaft
The FSM refers to it as a "short couple shaft" in section 16, titled Propeller Shafts.
The parts manual refers to it as an "intermediate tube". (16-02-3)
Laymen typically refer to it as an "intermediate shaft".

Tell that to the guy at Driveline Service, as I accepted the term he used. He'd been in the business for twenty years.

Newsflash to PwrWgnDrvr: Definitions to words are derived from common usage. For you to argue the term "jackshaft" does or does not include what Dodge called an "intermediate shaft" is therefore specious, becaise neither you nor Wikipedia has that authority. Even so I went to your Wikipedia link, and it doesn't support your exclusion. Here is their definition:

"A jackshaft, also called a countershaft, is a common mechanical design component used to transfer or synchronize rotational force in a machine.”

So, “completely different,” eh? Unless botth axle pinions are synchronized when in four wheel drive, there's a serious probem. Accordingly, that Wikipedia definition although pretty broad, does include the shaft coming out of the transmission to the transfer case with power extended to subsequent front and rear driveshafts. To continue from your cited source:

“A jackshaft is often just a short stub with supporting bearings on the ends and two pulleys, gears, or cranks attached to it (as a specific example - M). "In general, a jackshaft is any shaft that is used as an intermediary transmitting power from a driving shaft to a driven shaft."

Yup. The "intermediate shaft" as Dodge called it falls WITHIN that Wikipedia definition of "jackshaft" as a subset, albeit there is a gearbox in between shafts on the W series trucks. And if you still don't buy that try Googling images for the words "truck" and "jackshaft." Guess what you'll see? My guess is that the application of the term originated with long wheelbase industrial trucks that had a first "jackshaft" supported by a pillow bearing at the rear end followed by a second driveshaft to the rear axle(s).

Hence, I doubt seriously the original term is as explicit as you imply, meaning that your willful and hyperbolic mistinterpretation is what is “incorrect.” The applications of the term clearly derived from others over time, probably starting in the days of steam-powered English factories with overhead shafts and leather belts, very possibly with the specific originator (“Jack”) probably lost to history. Apparently you don't know him.

[Wellser]

Ok, thanks for the input. Do you think that could be overcome with a slip yoke eliminator?

I know absolutely nothing about such a beast.

Here’s a pretty cool video explanation.

Slip Yoke Eliminator:
https://4xshaft.com/blogs/general-tech- ... d-benefits

[Wellser]

Checked with a friend that runs a small one man transmission shop yesterday. He offered up a short shaft 727 core for under a hundred bucks that would provide the all parts needed (mainly the main shaft and tail housing) to convert yours to the shorter transmission length needed to make this work. That core plus the parts offered by Powerman in an earlier post to this thread on 22 Mar 23 (NP205, transfer case crossmember, and driveshafts) gets you almost all the way there. Outside of the incidentals that always pop up, you would need to find a shifter for the transfer case and the spacer blocks (factory or aftermarket) that go between the rear end housing and the rear springs to make the truck sit level with the 4WD front axle, but if I had the core transmission and Powerman's parts in hand I wouldn't hesitate to take it on if I hadn't already converted mine (68 128" WB 383 Camper Special) to overdrive (RH47).

Wow, that’s awesome! Thanks for doing that. (I’ve being talking with Powerman about those other parts.). It’s looking like I may have to make a run out to the west coast and pick up some parts.

[Conductorblg]

If you think you want Don's core transmission, PM me and I'll give you his shop number so you can phone him.

[Wellser]

Thanks again for all the great input. I think with a little help I could pull this project off, but I'm going to put this on the back burner for now. I still like the idea keeping this D200 as original as possible.

In the meantime, if anyone has any leads on a decent Power Wagon I could take on as my next project, let me know!

[soopernaut]

In the meantime, if anyone has any leads on a decent Power Wagon I could take on as my next project, let me know!

https://siouxfalls.craigslist.org/cto/d ... 08221.html

[PwrWgnDrvr]

I have an operable 70 W100, SWB, 383, NP445 available. More $ than the Iowa truck and not beat/rusted all to hell.

[Wellser]

In the meantime, if anyone has any leads on a decent Power Wagon I could take on as my next project, let me know!

https://siouxfalls.craigslist.org/cto/d ... 08221.html

Thanks for the heads up. I'll check that out!

[Wellser]

I have an operable 70 W100, SWB, 383, NP445 available. More $ than the Iowa truck and not beat/rusted all to hell.

PM Sent, thanks