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Ford Bronco Parts - Classic Vintage Early Bronco Parts

C6-203-205 Doubler

Tech article by admin and filed under Transfer Case

Now that I’ve covered the history behind my choice here are the details:

Note: I didn’t take very many pictures through the conversion and most of what I did were lost in a hard drive crash so I’ll try to explain as well as I can everything in detail and am providing what pictures I still have.

First I would need to obtain all of the parts. Here is the list I came up with:

1: C6 transmission with the short 4WD adapter that is 5 3/4″ long. I bought this in a local wrecking yard. The one I chose was from a 1989 Bronco that looked almost new inside. I paid $350 for the transmission plus another $120 or so to get a shift kit and off road torque converter. My brother put the shift kit in and checked the transmission over for free.

2: Ford NP 203 range box. (I chose the Ford one to avoid problems with spline counts) This was the hardest part to locate. I searched locally and finally called Stazworks and asked about other options. He happened to have one which he sold to me for $150. Shipping was steep but it came with the cover already set up with a fill plug in it.

NP 203 Range Box.
NP 203 Range Box.
NP 203 cover with fill plug already installed prior to arrival.
NP 203 cover with fill plug already installed prior to arrival.

3: Ford NP 205 transfer case. I bought one in a local wrecking yard for $100 and ordered a seal kit for it from JBG at the same time. When I was digging through the cases to find the one I wanted I just happened to run across a Ford NP 203 that I could have bought for $100 if I hadn’t ordered the one from Stazworks already. When I asked why they said they didn’t have one the day before they said it wasn’t listed on their inventory.

NP 205 Transfer Case.
NP 205 Transfer Case.

4: 203 to 205 Adapter kit (adapter and shaft). This I bought through Stazworks however it is actually built by Jed’s Machining. Cost is the same through either one which was $450. Shipping for this and the 203 range box was about $100 however it would have been a lot less without the heavy 203 range box included. I.E. Save some money and get it locally if you can. Note when I bought the adapter I was given a choice of having it come in 2 pieces so I could clock the NP 205 up where I wanted it before welding it together which is the option I chose.

NP 203 to NP 205 Adapter from Jed's Machining.
NP 203 to NP 205 Adapter from Jed’s Machining.

5: Steel and hardware to build a triple stick. (One for the 203 and two for the 205 so I could twin stick it) I chose to hold off on this until I could mock it up in the garage. I did order a twin stick shifter boot from JBG though.

6: Steel for a new cross member. I also chose to hold off on this to see what it would require.

This left a couple of items to consider still. First is that the driveline lengths would change, second is that the exhaust would need to be changed. I did a bit of preliminary measuring and it looked like I may get by with simply swapping the front and rear driveline’s. On the exhaust it was a good excuse to put headers on. I went to EBay and grabbed a set of stock Mustang Shorty headers off a 95 Mustang. They are stainless steel to keep them from rusting out and at about $45 including shipping the price couldn’t be beat.

I ordered and obtained the first 4 items around thanksgiving and they all arrived and sat on the floor until late in January. I was putting off doing anything with them due to the weather because I would need to do the work on it outside. (My Bronco will not fit through my garage door) At that point I was left no choice though when I was in the middle a big mud hole and the C4 finally gave out.

Now that I had all of the major parts and a really compelling reason to go out in the cold I began by pulling the C4 and Dana 20 out of my Bronco. I pulled them out as a single unit and put them on the floor of the garage. While I was under there I cut the complete exhaust out in 4 pieces and put it in the garage as well with hopes of using it after the conversion. I also pulled the auxiliary fuel tank out because I had decided to install a larger tank in back and run a single tank instead.

The old C4 and Dana 20 from my Bronco.
The old C4 and Dana 20 from my Bronco.

Next I assembled the parts in the garage on the floor next to the old C4 setup. This gave me a good idea of the length I would be dealing with and enabled me to look at where I would locate the shifters. I chose to locate them on a single bolt in one of the bosses that were already in the C6 4WD adapter. I chose the front one which looked like it matched up pretty close to the original shifter location on the C4/D20 setup.

The two C6 adapter bolt bosses.
The two C6 adapter bolt bosses can be seen in the upper right area of this photo.

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One Response to “C6-203-205 Doubler”

  1. r36130 Says:

    How is the rear drivehsaft angle on this? Do you have any measurements?

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