I doubt that the front axle of the 1991 W250 is a D60. My 1991 W350 had a D60 front and a D70 rear.

The exception MIGHT be if that 1991 W250 had a Cummins engine. In that year, you could get both the W250 and the W350 with the Cummins. Because of the extra torque of the CTD, they may have put D60s in the front of those with the CTD, just like they did with the W350. But I doubt they did it with the V8's.

1977 CJ-7, fiberglass body, AMC 360 w/ headers, DUI ignition, Edelbrock intake and Holley 4150 carb, TF999, Dana 300, 4.56 gears lockers, York air comp, 4" susp lift, 2" body lift, BFG 35" M-T tires, Megashifter, AGR pump & box, REP8000 winch.