: The Mustang ring gear bolts to the carrier and is driven by the pinion gear.
: The Mustang pinion gear turns the pinion gear, transferring power from the driveline.
: A shim is a thin piece of metal that is used to either adjust the fitment of other parts or take up a gap.
: This stands for “Independent Rear Suspension”, a housing which allows the left and right axles to move up and down separately from each other. 99-04 Mustang Cobras and S550 Mustangs are equipped with IRS systems.
: This is a collapsible spacer which installs on your Mustang's pinion and preloads the pinion bearings. Crush sleeves are not reusable and must be replaced if the pinion nut is loosened or removed.