Bakhjulsdrift

Bakhjulsdrift, or rear-wheel drive (RWD), is a drivetrain layout in which the engine’s power is delivered to the rear wheels. In traditional front-engined cars, power is transmitted via a driveshaft to a differential on the rear axle, which then propels the vehicle. Some designs use a transaxle at the rear, combining gearbox and differential in one unit. The engine is usually mounted longitudinally, though variations exist, including mid- or rear-engine configurations that still use rear-wheel drive.

Design variants include the rear suspension setup, which can be a live (solid) rear axle or independent rear suspension. Live axles with simple leaf springs are common in older cars and many trucks, while independent rear suspensions are widespread in modern passenger cars for improved ride and handling.

Performance and handling characteristics of bakhjulsdrift involve a balanced weight distribution and a steering feel that many drivers associate with precise control on dry pavement. During acceleration, weight transfer to the rear wheels can enhance traction for the driven wheels. On slippery surfaces, traction is reduced and understeer or oversteer can occur depending on conditions, tire grip, and vehicle setup. RWD vehicles generally require more skilled throttle and steering inputs to maintain control in adverse conditions compared with front-wheel-drive or all-wheel-drive layouts.

Context and usage: RWD has been common since the early days of motoring and remains favored in many sports cars, certain luxury cars, and some trucks. Front-wheel drive became prevalent for efficiency and packaging, while all-wheel drive offers enhanced all-weather capability. In Swedish terminology, bakhjulsdrift refers to rear-wheel drive, framhjulsdrift to front-wheel drive, and fyrhjulsdrift to four-wheel drive.