Rear Axles
Note on Dana 35 axles sometimes referred to as Dana 35C - The "C" does not stand for c-clip. It stands for "custom" meaning it came from Dana unfinished.
Note on 8.25 axles - none of these axles were used on XJs with ABS brakes. 8.25 axles are c-clip
If you have ABS, you have the Dana 35. Without ABS you could have either axle.
Dana 35 non c-clip - 27 spline, 1.18" diameter shafts, 7.58" ring gear, 2.62" axle tube - used 1984-89
Dana 35 c-clip - 27 spline, 1.18" diameter shafts, 7.58" ring gear, 2.62" axle tube - used 1990-01
Chrysler 8.25 - 27 spline, 1.17" diameter shafts, 8.25" ring gear, 3" axle tube - used 1991-96
Chrysler 8.25 - 29 spline, 1.21" diameter shafts, 8.25" ring gear, 3" axle tube - used 1997-01
Dana 44 non c-clip - 30 spline, 1.31" diameter shafts, 8.5" ring gear, 2.75" axle tube - used 1987-89 on some(not all) XJs equipped with towing package.
CHRY 8.25 has a oval cover and a flat area on the bottom, just above the red line in the pic.
Dana 35 has no flat spot and usually has 35C cast into the metal inside the red circle.