I have a 1979 f150 with a dana 44 front. there is no motor in it yet, but i locked in my hubs, and my transfer case to give the drive shaft a jiggle to check for u- joint play. I was able to turn the drive shaft 3/4's of a turn in both directions before it stopped, Do I have a wasted front end, or is there supposed to be that much backlash.

 

3/4 of a turn is WAY to much. I just did the same thing with mine for comparison and got about 1/16 total rotation of the yoke. A correct backlash allows for very little rotation of the yoke, but when you combine that with the play in the differential itself, between the differential and the axle shafts, and between the axle shafts and the hubs it can add up. But not (in my experience) 3/4 turn.

Only you can determine if the ring and pinion are trashed, or the differential, axle shaft splines, u-joints at the steering knuckles, hubs or all of the above.

Hope this helps.

-Scouder