The Dana 50 TTB (Twin Traction Beam) 4×4 front axle was used in the Ford F-350 from 1980 until a mid-year change in 1985, when the F-350 was fitted with the Dana 60 solid front axle. The Dana 50 was an option on the Ford F-250HD (Heavy Duty – over 8500# GVW) from 1980-1986. In 1987, the Dana 50 TTB replaced the Dana 44HD TTB in the F-250 becoming the only option. The Dana 50 TTB remained the front axle in the Ford F-250 4×4 until 1998. All Dana 50 TTB (and Dana 44HD TTB) trucks were leaf sprung and used a single gas shock. They did not use no coil springs and radius arms like the Ford F-150.

The Dana 50 TTB 3rd member (housing) will bolt to the Dana 44 / Dana 44HD axle beam, but you can’t swap any of the other parts to your Dana 44. The exception is the inner axle shaft and slip yoke on the passenger side. Click HERE for more information. The Dana 50 TTB shafts are larger than the shafts used on the Dana 44HD.

The Dana 50 TTB was is use from 1980 to 1998.

Dana 50 TTB Bolt In Right Side Inner Axle Shaft:

The 1980-1983 Dana 44 TTB, Dana 44HD TTB, and Dana 50 TTB all used a right (passenger) side inner axle shaft that was held in to the carrier housing by (3) bolts. After 1983, these axles were held in place by an internal c-clip. See more information at the bottom of this page.

Hot To Tell The Difference Between Dana 44HD TTB And Dana 50 TTB:

The Dana 50 TTB hubs are massive, the same size as the hubs on a Dana 60. These are about 4-inches across where the cap meets the actual “hub”. There is also a “50” stamped below the pinion yolk. Here’s a pic of a Dana 50 TTB hub:

If the axle is not in the truck, or missing the hubs, you can look at the axle shafts from the back side of the axle, and check the u-joint size. The Dana 44 TTB and Dana 44HD TTB both use Spicer 760x (formerly 297x) u-joints which are 2.188 inches wide, and the Dana 50 TTB uses a Spicer 799x (1350) u-joint which is 3.622 inches wide (see image below)

Specifications:

  • No carrier breaks
  • 30-Spline Axle shafts
  • Ring gear measures: 9.0 inches
  • Gear Ratios: 3.54:1 – 5.38:1
  • Pinion shaft diameter: 1.375 inches
  • Pinion shaft splines: 26
  • Axle shaft diameter: 1.50 inches
  • Axle spline diameter: 1.31 inches
  • Axle lugs: 8×6.5
  • Center section is steel
  • Fluid: SAE 80W-90 gear oil (2qts – always add fluid to fill plug level)

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 Right (Passenger) Side Inner Axle 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.