Suspension is the system of tires, tire air, springs, shock absorbers and linkages that connects a vehicle to its wheels and allows relative motion between the two. Suspension systems must support both road holding/handling and ride quality, which are at odds with each other. The tuning of suspensions involves finding the right compromise. It is important for the suspension to keep the road wheel in contact with the road surface as much as possible, because all the road or ground forces acting on the vehicle do so through the contact patches of the tires. The suspension also protects the vehicle itself and any cargo or luggage from damage and wear. The design of front and rear suspension of a car may be different.
A four-wheel drive, also called 4×4 or 4WD, is a two-axled vehicle drivetrain capable of providing torque to all of its wheels simultaneously. It may be full-time or on-demand, and is typically linked via a transfer case providing an additional output drive shaft and, in many instances, additional gear ranges.
Front-wheel drive (FWD) is a form of engine and transmission layout used in motor vehicles, in which the engine drives the front wheels only. Most modern front-wheel-drive vehicles feature a transverse engine, rather than the conventional longitudinal engine arrangement generally found in rear-wheel-drive and four-wheel-drive vehicles.
In automotive design, a front-engine, front-wheel-drive (FWD) layout, or FF layout, places both the internal combustion engine and driven roadwheels at the front of the vehicle.
In automotive design, an RR, or rear-engine, rear-wheel-drive layout places both the engine and drive wheels at the rear of the vehicle. In contrast to the RMR layout, the center of mass of the engine is between the rear axle and the rear bumper. Although very common in transit buses and coaches due to the elimination of the drive shaft with low-floor buses, this layout has become increasingly rare in passenger cars.
In automotive design, an RMR, or rear mid-engine, rear-wheel-drive layout is one in which the rear wheels are driven by an engine placed with its center of gravity in front of the rear axle, and thus right behind the passenger compartment. Nowadays more frequently called 'RMR', to acknowledge that certain sporty or performance focused front-engined cars are also "mid-engined", by having the main engine mass behind the front axle, RMR layout cars were previously just called MR, or mid-engine, rear-wheel-drive layout), because the nuance between distinctly front-engined vs. front mid-engined cars often remained undiscussed.
Rear-wheel drive (RWD) is a form of engine and transmission layout used in motor vehicles, in which the engine drives the rear wheels only. Until the late 20th century, rear-wheel drive was the most common configuration for cars. Most rear-wheel drive vehicles feature a longitudinally-mounted engine at the front of the car.
A transaxle is a single mechanical device which combines the functions of an automobile's transmission, axle, and differential into one integrated assembly. It can be produced in both manual and automatic versions.
In automotive engineering, a mid-engine layout describes the placement of an automobile engine in front of the rear-wheel axles, but behind the front axle.
A drive shaft, driveshaft, driving shaft, tailshaft, propeller shaft, or Cardan shaft is a component for transmitting mechanical power, torque, and rotation, usually used to connect other components of a drivetrain that cannot be connected directly because of distance or the need to allow for relative movement between them.
The Z platform or Z-body automobile platform designation was used on three different types of vehicles made by General Motors not including their trucks.
The Hotchkiss drive is a shaft drive form of power transmission. It was the dominant means for front-engine, rear-wheel drive layout cars in the 20th century. The name comes from the French automobile manufacturer Hotchkiss, although other makers, such as Peerless, used similar systems before Hotchkiss.
A torque tube system is a power transmission and braking technology that involves a stationary housing around the drive shaft, often used in automobiles with a front engine and rear drive. The torque tube consists of a large diameter stationary housing between the transmission and rear end that fully encloses a rotating tubular steel or small-diameter solid drive shaft that transmits the power of the engine to a regular or limited-slip differential. The purpose of a torque tube is to hold the rear end in place during acceleration and braking. Otherwise, the axle housing would suffer axle wrap, which is when the front of the differential lifts excessively during acceleration and drops down during braking. Its use is not as widespread in modern automobiles as is the Hotchkiss drive, which holds the rear end in place and prevents it from flipping up or down, during acceleration and braking by anchoring the axle housings to the leaf springs using spring perches.
In automotive design, a front-mid-engine, front-wheel-drive layout is one in which the front road wheels are driven by an internal-combustion engine placed just behind them, in front of the passenger compartment.
The Chevrolet Engineering Research Vehicle (CERV) is a series of Chevrolet experimental cars. Chevrolet Staff engineer, designer, and race car driver Zora Arkus-Duntov started development of the CERV I in 1959, and began work on the CERV II in 1963. Chevrolet chief engineer Don Runkle and Lotus' Tony Rudd discussed creating a new show car to demonstrate their engineering expertise in 1985; It would become the CERV III. Corvette chief engineer Dave Hill unveiled the CERV IV in 1993, a test vehicle for the 1997 C5 Corvette.
In automobile design, a rear-engine design layout places the engine at the rear of the vehicle. The center of gravity of the engine itself is behind the rear axle. This is not to be confused with the center of gravity of the whole vehicle, as an imbalance of such proportions would make it impossible to keep the front wheels on the ground.
The powertrain layout of a motorised vehicle such as a car is often defined by the location of the engine or motors and the drive wheels.
The following outline is provided as an overview of and topical guide to automobiles:
Jean-Albert Grégoire was one of the great pioneers of the front-wheel-drive car. He contributed to the development of front-wheel-drive vehicles in two ways. The first way was in developing and promoting the Tracta joint, which was, until manufacturing techniques had progressed sufficiently to allow the successful manufacture of the constant velocity joints commonly in use today, the preferred choice of most manufactures of vehicles that had driven front wheels. Tracta joints were used by many of the pioneers of front-wheel drive, including DKW between 1929 and 1936 and Adler from 1932 to 1939 as well as the cars designed by J A Grégoire that will be mentioned later. The Tracta joint was fitted to most of the military vehicles that had driven front wheels used by most of the combatants in the Second World War. They included Laffly and Panhard in France, Alvis and Daimler in the UK and Willys in the United States that used the joint in a quarter of a million Jeeps and many others. This was to continue after the war, the first Land Rover being so fitted.
A rear-engine, front-wheel-drive layout is one in which the engine is between or behind the rear wheels, and drives the front wheels via a driveshaft, the complete reverse of a conventional front-engine, rear-wheel-drive vehicle layout.
