If you're replacing the lower ball joint, please note that AMG has changed the fasteners that secure the ball joint to the lower control arm. You will need to replace the bolts, the lockwashers, and the locknut, all three. The locknut has kept the same part number, but uses a different thread size: hence you cannot simply replace the locknut while retaining the old washers (note: nonlocking) and bolt. AMG has all of this in a kit, which I recommend that you buy, as it will save you the eleventy-odd hikes to the hardware store that I have made in the last couple of days.

Each joint uses four grade-8 0.375", 24-thread (fine), 1.5" long bolts; eight grade-8 split-ring lockwashers (though I imagine camlocks would work just fine here); and - here's the kicker - four "Stover style" 0.375" 24-thread locknuts.

A Stover style locknut has no nylon collar; instead, it seems to depend on having a slightly elliptical hole. They are favored by the builders of racing cars and hydroplanes.

Ben (these boots were made for walkin')