General information about mechanical transmission (Mazda 3 BK)

The gearbox converts the torque transmitted from the engine in magnitude and direction. This is necessary to ensure optimal speed and cross-country ability of the vehicle, high efficiency of engine operation and vehicle movement in reverse. In addition, the gearbox disconnects the engine and transmission when the vehicle is stopped and parked, as well as when it is moving by inertia with the engine running.

All models with manual transmission are equipped with a five-speed gearbox, combined into one unit with a differential and final drive. Torque from the engine is transmitted through the gearbox and final drive to the differential, which in turn distributes it between the drive shafts.

The five-speed manual transmission is equipped with a mechanism for synchronizing all gears.

Fig. 3.24. Cross-section of the manual gearbox of the Mazda 3: 1 – 1st gear drive pinion; 2 – 2nd gear drive pinion; 3 – 3rd gear drive gear; 4 – 4th gear drive pinion; 5 – 5th gear drive pinion; 6 – reverse gear; 7 – driven gear of 1st gear; 8 – 2nd gear driven gear; 9 – 3rd gear driven gear; 10 – driven gear of 4th gear; 11 – 5th gear driven gear; 12 – synchronizer clutch (reverse gear); 13 – intermediate reverse gear; 14 – differential

Fig. 3.25. Gearbox in block with final drive: 1 – oil seal (differential); 2 – car speedometer sensor; 3 – manual gearbox in block with final drive; 4 – switching mechanism; 5 – gearbox oil