i have 2 dana 44 knuckles, i think, the ball joints look the same, same size the only difference is one has the caliper bolt holes in the knuckle, the other uses the backin plate, these are both flat top, does anyone know why the different caliper mounts and what they go on?

As far as I am aware all D44's on GM's used a backing plate from 72 up. I know some of the early 44's that were used in the late 60 after the Napco may have had closed knuckle. Unless it's real early 44 from the 60's I don't think the one with the mount is off a GM. As far as I'm aware all Jeeps would have a steering arm on the passenger side. Might be a ford unit off a EB Bronco. Maybe off a Dodge. Dodge uses the same set up as GM with the short drag link on the driver side. Ford ran the drag link off the tierod.
There was recently some pictures of a D44 axle in the General 4x4 section that had a Driverside arm that the box was mounted behind the axle. Don't remember what they said it came off. Maybe a full size IH Travel all or truck. Was a good clear picture. I wasn't paying attention to the caliper mount but if you can find that post you might be able to see if it's like the knuckle you have. It was about a week or so ago.

From my junkyard searching all summer in building up my truck, only knuckles i saw w/ the built in caliper brackets were on the fords. Chevy's and jeeps all use the bolt on caliper brackets that bolt on between the knuckle and the spindle.

so i guess i have a flat top knuckle for a dana 44 from a ford and one from a chevy

Originally posted by aggielr
so i guess i have a flat top knuckle for a dana 44 from a ford and one from a chevy

yes that is correct