Buy 2006 Ford F-150 4.2L Triton V6 A/T RWD XLT Extended Cab Pickup Fleetside Leaf Spring Insulator Suspension, Make, Prone - OEM Ford Part # ML3Z5586B (ML3Z-5586-B)

Spring. Pad. Bracket bumper. Insert. Leaf Insulator.
Insulator used for the Leaf Spring. Included with: Spring.

Leaf Spring Insulator

Fits F-150

Rear.
Suspension Leaf Spring - Repair or Replace
Your leaf springs are not especially prone to failure, but excessive rust can make them more prone to failure. Contact your local Ford service department to have the suspension system in your 2006 Ford F-150 evaluated and have the leaf springs replaced if necessary.