TransaxleLayout

Transaxle layout is a drivetrain arrangement in which the transmission and final-drive differential are housed in a single unit, placed near the opposite end of the powertrain from the engine. This configuration is common in front-engine, rear-drive cars where a rear transaxle provides the final drive, as well as in mid-engine or rear-engine designs where the transaxle sits close to or at the rear axle. The transaxle combines gear selection and differential gearing in one housing and connects to the engine by a driveshaft or, in some mid- or rear-engine layouts, directly to the crankshaft.

The main purpose of a transaxle is to optimize weight distribution, packaging, and overall drivetrain stiffness. By locating the final-drive components near the driven wheels, manufacturers can achieve more favorable balance, reduce driveline length in certain configurations, and improve interior layout for performance models.

Advantages include improved weight distribution and handling in suitable configurations, potentially more compact and balanced packaging, and the possibility of centralized mass that aids chassis rigidity. Disadvantages include added cost and mechanical complexity, potential maintenance challenges due to the remote location of the transaxle relative to the engine in some layouts, and thermal management considerations since transmission and differential share a single unit in a confined space.

Notable examples are found in front-engine cars that use a rear transaxle, such as certain Porsche models (for instance, the 924, 944, and 968) to achieve better balance. Mid-engine and rear-engine sports cars also employ transaxles to optimize traction and weight distribution. In front-wheel-drive applications, the transaxle unit often aggregates the transmission and differential at the front axle for compact packaging.