How to Interpret Fast Gearbox Model Numbers?
3 Answers
Fast's gearbox numbering rule is: number of forward gears + gearbox structure type + input torque + gear ratio code. Below is a detailed explanation of the meanings of these codes: 1. The first digit of the number is usually the letter C or F. C is the first letter of the English word "China," representing China. "F" stands for the Fast brand. 2. The second and third digits indicate the number of forward gears in the gearbox. According to Fast's product spectrum, there are 5-speed, 6-speed, 7-speed, 8-speed, 9-speed, 10-speed, 12-speed, 16-speed, 20-speed, and 24-speed gearboxes, with the most common being 8-speed, 9-speed, 10-speed, 12-speed, and 16-speed gearboxes. 5-speed, 6-speed, and 7-speed gearboxes are single-box, while gearboxes with 8 speeds or more are dual-box with a main and auxiliary box structure. 3. The fourth digit represents the gearbox structure type, where J stands for mechanical transmission, and D stands for an integrated single-box structure gearbox. 4. The fifth digit indicates the number of intermediate shafts in the gearbox, with S representing a dual intermediate shaft. Currently, all Fast gearboxes feature a dual intermediate shaft design, which offers advantages such as high torque capacity, smooth transmission, and compact axial dimensions. If an additional S follows the first S, it indicates that the auxiliary box has a triple intermediate shaft structure. 5. The sixth digit represents the gear type. QX stands for "full helical gear," meaning both the main and auxiliary boxes use helical gears; if only X is present, it means only the auxiliary box uses helical gears. 6. The seventh digit indicates the material of the gearbox housing. L represents an aluminum alloy housing, while an iron housing is not denoted by any letter. 7. The following numbers represent the gearbox's maximum input torque. Multiplying this number by 10 gives the maximum torque the gearbox can withstand.
As a truck driver with over a decade of experience, I can explain the FAST gearbox model like 9JS119T. The '9' indicates it has nine forward gears, which is particularly useful when climbing hills with heavy loads. 'JS' signifies a heavy-duty transmission with synchronizer design, suitable for large vehicles. The number '119' suggests it can handle approximately 1190 Newton meters of torque—the higher the number, the greater the load-bearing capacity. The suffix 'T' might indicate turbocharger compatibility or a specific improved version. Understanding these details helps owners choose the right parts during maintenance, extending the transmission's lifespan. In practice, always check the manual for confirmation, as there may be minor variations across different years. Remember to regularly inspect the fluid and seals to avoid major repairs. Decoding the model is simple, but the details matter for safe driving.
From an average car owner's perspective, deciphering Fast Gear transmission models like the 6DS80 is straightforward: the number 6 indicates it has six gears in total, making operation less complicated; the letters DS denote the double-cone synchronizer type; the number 80 refers to a torque capacity of approximately 800 kg·m. If there's a suffix like T, it might indicate a specific series. Understanding these details helps you avoid being misled at repair shops—you can simply quote the model number when replacing parts. The model number also relates to vehicle compatibility, so it's crucial to verify this when buying used cars to avoid mismatches. Consulting experienced drivers or referring to official manuals provides the most accurate information.
