1980-1997 Ford Dana 50IFS Front Axle Identification IDN-135

Ford was the only vehicle manufacturer to use Dana Twin Traction Beam® Independent Front Suspension Axles which can be found on 1980-1997 model year Ford 4x4s. The Twin Traction Beam® IFS Axle line includes the coil spring Models 28 and 35 found in Bronco II, Explorers and Ranger pickups, the Model 44 which was used in fill size Broncos, F-150 (coil springs), and light duty F-250 pickups (leaf springs), and the leaf sprung 4500 to 4600 pound rated Model 50IFS axle in heavy GVW F-250 and 1980-1985.5 F-350 trucks.

External Identification Characteristics of Ford Dana 50 Twin Traction Beam Independent Front Suspension Front Axles:

• Leaf Spring Suspension
• Left and Right Axle Beams formed from stamped and welded steel
• Outer End of 8 Bolt, Internally Splined Wheel Hub  is approximately 4-3/16" in diameter
• Axle Shaft Universal Joints have External Snap Rings
• Dual Piston Brake Calipers
• Rated Front Axle Capacity on Truck Data Plate will be 4500 to 4600 pounds

Major Design Changes for 1980-1997 Ford Dana 50 Front Axles and the approximate years used:

1. 1980-1982 Right Differential  Output Shaft retained by 3 Bolt Thrust Plate
2. 1983-1997 Right Differential Output Shaft retained by Snap Ring on inboard end
3. 1980-1985 Brake Caliper Assemblies retained by single slide and tension spring at lower end
4. 1986-1994 Brake Caliper Assemblies retained by 2 Rubber Isolated Brake Caliper Pins per side
5. 1995-1997 Brake Caliper Assemblies Attach to Steering Knuckle with 2 Bolts
6. 1980-1985.5 Years Dana 50IFS Axle used in F350

More  about the 1982-1983 Differential Output Shaft Change:
Right Differential Output Shaft: The major difference between 1980-1983.5 and 1983.5-1997 Ford Dana 50IFS front axles is the way the right differential output shaft is supported and retained. The early axles use a pressed-on taper roller bearing and an external bolt-on retaining flange. Later production axles use a straight roller bearing pressed into the differential housing and the axle shaft is retained by a snap ring inside the differential next to the differential side gear. The early right diff output shafts could be pulled without removing the differential housing from the axle beam with a special slide hammer puller attachment, but seal replacement also requires the bearing be replaced. For later axles, you MUST remove the differential housing from the axle beam to access the snap ring, but once it is out replacing the right seal is quick and easy.