The GM axle assembly is the central shaft under the car frame that links the vehicle to the rotating drive wheels. Composed of a network of GM ball joints, bearings and bushings, the axle allows the wheels to turn while keeping their positions relative to one another and to the vehicle frame. A GM axle typically installed on the rear end of the car is fixed to a rotating gear, while a GM axle with GM ball joints are installed on the front wheels of the vehicle where steering capability is a chief requisite. The well oiled joints and bearings in the mounting points of the GM axle assembly keep the car under a tight rein from vehicle cruising to revved-up driving. Necessary in a slew of vehicle operations ranging from accelerating, braking, and steering, the GM axle assemblies sport various structural designs and settings. A world standard GM axle assembly consists of one shaft connecting the right wheel to the left. It is a design consideration aimed at souping up the car in terms of weight load capacity and resistance to stress. Such design is still in use on off-road cars and heavy-duty GM vehicles. For sedans and compact cars, the drivetrain sports a split GM axle design, where individual wheels are attached to an independent shaft. Because each wheel runs on its own set of GM ball joints, independent suspension of the wheels is available and allows for a smoother ride. Additionally, the split GM axle assembly allows various speeds of wheel rotations when the car hugs curves and is engaged in an off-road drive condition, improving traction and prevent excessive tire wear. The GM axle assembly is usually reinforced inside a steel billet. Also, a tandem GM axle can be used on a number of GM models requiring higher weight load capacity. The GM ball joints likewise are ordinarily enclosed in a steel casing, which gives protection to the joints against gunk and road salt that may otherwise get into the assembly and affect vehicle operations. A specialized type of GM ball joint, the motion control ball joints, is fitted with an internal spring aimed at preventing vibration problems in the linkage. It is designed to eliminate bumps and bounces in the suspension, isolating the GM axle joints from the chronically uncomfortable ride of such drive conditions.