Twin-Traction Beam Explained

Twin-Traction Beam (TTB) is an independent suspension system for front drive axles in four-wheel drive Ford F-Series trucks and sport utility vehicles.

Background

Twin-Traction Beam was invented by John A. Richardson and Donald G. Wheatley of Ford Motor Company covered by US patent 3,948,337 issued April 6, 1976. The patent name was “Independent front suspension for front-wheel drive” which was assigned to Ford Motor Company.^{[1] [2]}

The Dana Holding Corporation manufactured the TTB axle for Ford. It uses a universal joint in the center that allows the wheels to move independently of each other. The differential is offset to the driver's side, and a slip yoke is used on the long axle side to allow the shaft to change length. The TTB axles are variations of the Dana 28, Dana 35, Dana 44, and Dana 50.^[3]

Applications

Common applications include:

• 1980–1997 F-150/F-250
• 1991–1994 Ford Explorer
• 1984–1990 Ford Bronco II
• 1980–1996 Ford Bronco
• 1983–1997 Ford Ranger (North America)
• 1993-1997 Mazda B series
• 1991-1993 Mazda Navajo

See also

• Corvette leaf spring
• MacPherson strut
• Torsion beam suspension
• Weissach axle – a variant of Double wishbone suspension with a short link at the front pivot bushing of the lower A-arm

Notes and References

1. Web site: US Patent for Independent front suspension for front wheel drive Patent (Patent # 3,948,337 issued April 6, 1976) . patents.justia.com . May 6, 2021 .
2. Bedi . G.S. . W.H.R. . Lake . 1979 . Evolution of the New Ford Light Truck Four Wheel Drive Independent Front Suspension . 88 . SAE Transactions . 3654–3699 . 6 May 2021.
3. Web site: Dana 44 & Dana 44HD TTB Front Axles . Blue Oval Trucks . 6 May 2021.