I'm looking for info on how to fit a 203 low range case between my C4 and Dana 20 T-case. Any do it your self info you have.

I've pulled a 2wd C4 shaft and have access to a 203, what's next?

Brad N

You will almost need to buy the kit to put a 203 behind a np435 and infront of a dana 20. Their is an adapter plate and a new shaft that mates the 203 to the 20. You are looking at around $1100. for the kit if no one has a home brew way. Good luck!
:beer: :usa: :beer: :nuke: :nuke:

I don't plan on buying a kit, let alone for over $1000! (who sells the kit? Link?)

I'm looking for site's like the following:

http://www.bc4x4.com/chrisw/projects/powertrain/tcase1.asp

http://www.bc4x4.com/tech/2000/gordtcases/gordtcases.cfm

Regular guys with know-how who've done something similar.


Anyone know the spline count and depth of the shaft that enters the 203? The differences between Ford, Chevy and Dodge. Why does everyone recommend the Dodge unit?

Brad N

Looks like the Dodge 203 has the smallest input at 27 splines with a diameter of 1 3/16". Ford is 29 at 1 1/4".

Now to see if the C4 shaft has enough to be re-splined.

I thought the Ford 203 was 31 spline??

Originally posted by FordPowr
I thought the Ford 203 was 31 spline??

As far as I can tell Ford used the fewest spline counts vs Dodge and Chevy. I knew of Ford using 29 and read about 33 (or 32, can't remember)

I wouldn't doubt it though.


I'm very close to seeing if this is do-able! Just need to find a 2WD C4 for measurements now. Any takers that want to take the tail cone off and take some measurements for me?

Here is a shaft from a rear 2wd C-4.
(It's a crap shoot if the picture comes up as it's geocities)

Anyone know how far the governor sticks out of the rear of the C4?

http://77cj.littlekeylime.com/Links/c42wdsft.gif

ok we need more info here. I also want to do a dual set up on my own . but need just a few more pics of one:flipoff2: :smokin:

I think he quit working on it because of the length. It would come out longer than he wanted.

Well, I'm still looking into this this. It's just to cold to work in the garage in the Minnesota winter.

Good news, It looks like the C4 2WD shaft can be used, while leaving the governor on. IF the picture shows above (20% Chance) you'll see there is a small area that is large enough to have it re-splined to fit a Dodge 27 spline 203.
It's an 1 3/4 inches long by 1 1/4" thick. The Dodge need 1 3/16" thick shaft for resplining if not larger, like 1 1/4" !

Now All I have to do it gets the parts together and see if it'll work. Looks ok and only adds a little (~5 inches) in length.

Ford is 31 spline 1.375".
Charlie

http://77cj.littlekeylime.com/Links/c42wdsft.gif
Ok, on the thick part of the shaft, 1 1/4" diameter and 1 3/4" long area. The governor sticks out to leave 1 1/4" behind this, thus leaving this for re-splinging.
The 203 input area is about 1 3/4", with the first 1/4" not having any splines, this area can be ground off leaving 1 1/2" splind area.
A close enough match for me. Looks like this can be done!
I'm not sure when I'll do this, I may wait to move my rear axle back 2" first.