Ball joints are a consumable item for the SL-C. Depending on their origin, and their usage, they can wear out in as little as a couple of thousand miles. When you replace them, it’s a good idea to replace them with a better quality item than was originally specified on your car. The QA1 balljoint is a race-quality one, and is both greasable (many OEM ball joints are shipped without a zerk fitting) and rebuildable.

However, even though they are listed as a direct replacement, they don’t have the exact dimensions of the OE unit. Installing them without this spacer usually means the ball joint will bind or suspension travel will cause the wheel rim to grind against the steel base of the ball joint.

We’ve developed a simple aluminum spacer makes them fit perfectly. These are waterjet-cut out of durable aluminum and are easy to install with the new ball joint. You’ll need 1 for each side, and these are intended to fit only on the front of the car. Tested and validated with the old-style uprights, we assume they work equally as well with the newer post-2010 uprights as well.

See the explanation and more pictures in the balljoint section of the wiki.

Contact Will for more info, including shipping info.