The concept of maintenance over repair has gained widespread acceptance among truck drivers, but truck maintenance isn’t simple. Regularly changing various oils alone can be daunting. Previous installments have covered engine oil, and today’s installment of Parts Knowledge will focus on gear oil and related maintenance issues.
Gear oil, also known as gear oil, is a crucial lubricant formulated with a petroleum-based or synthetic lubricant, enhanced with extreme pressure anti-wear agents and oiliness enhancers. It is primarily used in various gear transmissions, such as transmissions and drive axles.
Gear oil primarily lubricates the various gears, helping to dissipate heat during driving, reduce gear wear, extend gear life, prevent rust, and improve transmission efficiency.
As a crucial link in the powertrain, the gear faces of the transmission and rear drive axle are subject to significant pressure. Once the gear oil film is broken, the gear faces will directly contact each other. High torque can easily damage the gears, leading to vibration, unusual noise, and other issues in the drive axle.
Gear oil should generally be changed every 60,000 kilometers. It must be changed before its expiration date. Similar to engine oil, gear oil has its own grading system.
Internationally, the American Petroleum Institute (APL) performance classification system is generally used to categorize gear oils into five basic types: GL-1, GL-2, GL-3, GL-4, and GL-5.
In my country, automotive gear oils are primarily classified into three grades based on performance:
L-CLC: Made from refined mineral oil with antioxidants, rust inhibitors, antifoaming agents, and a small amount of extreme pressure agents. Suitable for manual transmissions and drive axles with curved bevel gears in vehicles with moderate speeds and relatively demanding loads.
L-CLD: Made from refined mineral oil with antioxidants, rust inhibitors, antifoaming agents, and extreme pressure agents. Suitable for various gears operating under low-speed, high-torque conditions or high-speed, low-torque conditions, particularly hypoid gears used in buses and other vehicles.
L-CLE: Made from refined mineral oil with antioxidants, rust inhibitors, antifoaming agents, and a relatively large amount of extreme pressure agents. Suitable for various gears operating under high-speed impact loads, high-speed low torque, and low-speed high torque, particularly hypoid gears in buses, trucks, and other vehicles.
The extreme pressure agent content in these three grades of gear oil gradually increases. High-horsepower, high-torque vehicles like trucks are best suited for L-CLE grade gear oil.
Of course, this is just a simple classification; the specific selection should be considered comprehensively, considering both the vehicle type and the operating environment. Light and medium trucks, for example, have lower load capacities and their gears are not subject to particularly heavy loads, so the extreme pressure and anti-wear requirements for gear oil are relatively low. Heavy trucks, on the other hand, which transport long distances and bear heavy loads on their gears, require gear oils rated GL-4 or higher.
● Postscript:
Maintenance is worse than repair. Spending extra time maintaining your vehicle can significantly reduce the chance of breakdowns. Therefore, we remind all truck drivers to remember to change their gear oil regularly to keep their vehicles in good condition.
