| 4x4 1999-2004 | 4x4 2005 and later | 4x2 | |
|---|---|---|---|
| Springs | Leaf | Coil | Coil (Twin I-Beam) |
| Axle located by | The leaf springs | Radius arms and a track bar | I-beams |
| Lift method | Leaf packs, shackles and hangers | Spacers, coils, caster correction | Not covered here |
Radius arms
Diesel World's swap guide lists what the coil front end includes: coil buckets, coil springs, radius arms with frame brackets, a track bar, a sway bar, and steering from the pitman arm down. A radius arm sets the axle's fore-aft position and caster. When you lift the truck, the arm angle and caster change.
Track bar
The track bar keeps the axle centered side to side. As on any solid axle, it and the drag link should stay close to parallel to limit bump steer (MotorTrend, EVO).
Where this comes from
- Diesel World: 05+ Super Duty axle swap guide
- SuperMotors: 1999-2007 Ford F-250 specs and history
- MotorWeek: 2005 Ford F-Series Super Duty road test
- Ford: 2013 F-Series Super Duty technical specifications (PDF)
- MotorTrend (4-Wheel & Off-Road): 4x4 truck steering system parts
- EVO Manufacturing: JL/JT front track bar steering correction
Last reviewed 2026-10-19. General information only: Ford and your kit maker's instructions come first.