Differances in the Dana 20's

I've searched and searched and can't find my answer so here I am asking the experts,

Is there any difference between the Dana 20 transfer cases? Differences between years and differances between ones used with an automatic and standard trannies?

I want to rebuild on from an auto and install it behind a Std. can I do it?

Thanks

1968 frame off jeepster
1969 spring over jeepster

 

Maybe this will help until someone who knows your exact answer
http://www.novak-adapt.com/knowledge/model_20.htm

 

yes. I learned this one the hard way.

there are a few variations that I know of.

1) some later d20's have a 27-spline rear output, identical in diameter and spline to the d300 instead of the normal 10(?) spline output
2) some d20's, possibly those from auto trans application, do not have the transmission mounting face recessed for the two shift/idlergear? rails that protrude about 1.4" from the mounting face of the transmission. (they are to the right and down from the trans output shaft as you look at the trans from the back)
3) There are two different style shifters. One is the shifter wehre the handle is hinged, and attaches to the shift rails via a crossbar. The other is a "ball in socket" style where the bottom of the shifter and the ends of the shift rails meet in an enclosed" box" The sifters are also extended various legnths from the t-case depending on trans and application that it came from.

When I put the tera low in my jeep i bought an extra d20 and had hte teralow put in that.

When I removed my old d20, i found these differences. I had to get the mounting face machined to accomadate those two transmission outcroppings, but other wise I considered the 27 spline a strength upgrade, and i prefer the simpler shifter, as it seems to be more direct, and was certaintly less sloppy in its engagment.


Unfortunately I ahve no way to guide you as to where most of these differences occur vehicle wise. IE a commando gets this one a j-truck that one and a cj this third one. The only positive way to tell would be to compare the cases side by side on the ground. That being said it is possible to interchange them with a few simple modifications.

 

You want the gear chart, if you have not found it already:
http://www.novak-adapt.com/knowledge/transfer_case_gears_grid.htm