What does the term 'final drive' mean in automobiles?
3 Answers
In automotive terminology, the 'final drive' is technically known as the final reduction gear. Since the transmission is colloquially referred to as the 'gear box', and the intermeshing teeth of transmission gears resemble dental occlusion with precise alignment, while the final reduction gear constitutes the last-stage deceleration mechanism, it's thus called the 'final drive'. The main reducer consists of one or multiple sets of reduction gears. Located within the drive axle, the main reducer serves as a mechanism to alter torque and rotational speed. Its fundamental function is to amplify the torque received from the transmission or universal joint drive while simultaneously reducing rotational speed and changing the direction of torque transmission. The term 'final drive oil' is a conventional designation – essentially, it refers to gear oil, also known as differential oil. Final drive oil is used in various gear transmission devices to prevent tooth surface wear, scoring, sintering, etc., thereby extending service life and improving power transmission efficiency. Gear oil should possess excellent anti-wear and load-bearing properties along with appropriate viscosity. Additionally, final drive oil must demonstrate good thermal-oxidative stability, anti-foaming characteristics, water separation performance, and rust prevention capabilities. The operating temperature of gear oil is generally lower than that of engine oil and largely fluctuates with ambient temperature changes. Vehicle gear oil temperatures typically do not exceed 100°C. Generally, final drive oil should be replaced every 80,000 to 100,000 kilometers, though specific intervals may vary by vehicle model – consult the maintenance manual for precise recommendations.
As a seasoned veteran in car modifications, I can tell you that the 'car tail gear' actually refers to a component of the differential, specifically the deceleration device on the vehicle's rear axle. Modifying the tail gear is primarily about altering the gear ratio to make the car accelerate more aggressively from a standstill, which is especially thrilling for straight-line racing. I've personally experimented with installing a larger tail gear, and the take-off was incredibly quick, making the engine feel much more powerful. However, at high speeds, the RPM tends to run higher, fuel consumption increases, and the noise level goes up. If not done correctly, the transmission system can wear out quickly, leading to expensive repair costs. For regular maintenance, remember to check the differential fluid to prevent leaks or contamination. Modifications should be tailored to the vehicle model and driving habits—if you're unsure, it's best to consult a professional shop rather than tinkering blindly. In the end, playing with the tail gear can enhance driving pleasure, but striking the right balance between performance and reliability is key.
As an average driver, my understanding of the differential (commonly known as 'tail gear' in Chinese) is that it's part of the differential system, primarily functioning to reduce speed and adjust rotation at the vehicle's rear wheels. After decades of driving, I've noticed that the differential affects acceleration smoothness, with factory settings typically favoring fuel economy. If you feel sluggish starts or unusual noises during turns, it might be related to differential wear. During routine maintenance, technicians check whether oil seals and gears are functioning properly – aging issues should be repaired promptly to prevent decreased transmission efficiency. During high-speed driving, the differential also enables wheels to rotate independently, preventing slippage. Simply put, this component makes vehicle operation more stable and efficient. Don't neglect it – maintaining proper lubrication saves considerable trouble.
