Buy 2011 Ford F-350 Super Duty Coil Spring Damper. Suspension Coil Spring - Repair or Replace Your Springs, Stop, Failure - OEM Ford Part # NK4Z4730B (NK4Z-4730-B)

Bumper.
A component (mounted in the center of the spring) which cushions the spring as it is compressed. Auxiliary spring. Boot. Bushing stop. Coil Spring Damper. Knuckle. Lower Control arm. Shock. Spring seat stop. Suspension crossmember. Track bar. Trailing arm stop. Wedge.

Coil Spring Damper

Fits E-Transit

Suspension Coil Spring - Repair or Replace
Your coil springs are not especially prone to failure, but if they have been cut, clamped, or heated to have the vehicle lowered, your 2011 Ford F-350 Super Duty might benefit from replacing the strut springs. Excessive rust can make the springs more prone to failure. Contact your local Ford service department to have your suspension system evaluated.