Axle retaining clips are small pieces of metal that hold axle shafts and CV axles in place in the differential or transfer case of a vehicle. Axle retainer clips can be both circular, especially in CV front axle vehicles, or c-clip retainers in rear- and four-wheel drive vehicles. The retainer clips are typically small pieces of metal that do not bear any portion of the vehicle's weight or forward motion. They are engineered only to prevent the axle from shifting.
CV axles are common in late model, front- and all-wheel drive vehicles and feature a multi-component front drive axle with a plastic boot or cover. Axle retaining clips sit atop the piece of the axles furthest from the wheels. The axle retainer in this setup is typically a small, circular metal band that holds the axle assembly in place to prevent horizontal shifting of the axle.
Rear- and four-wheel drive vehicles with c-clip style axle retainers typically use a straight axle or two-piece axle assembly for front drive wheels. The c-clip axle retainer clips to a button on the inner end of the axle shaft inside the differential and prevents the axle from shifting horizontally. Axle shafts using a c-clip retainer cannot be removed without first opening the differential and removing the c-clips.