
It should be changed approximately every 20,000-30,000 km. Below is relevant information: Time: The interval may vary depending on the oil brand, but generally, it should be changed every 20,000-30,000 km. For new vehicles, the rear axle oil should be replaced during the 12,000 km maintenance, and then inspected every 24,000 km thereafter. If noticeable discoloration or thinning is observed, immediate replacement is necessary. Precautions: Different types of hypoid gear lubricants should not be mixed, as this may cause the lubricant to deteriorate and corrode the main and pinion gears. Avoid introducing moisture during storage and filling of gear oil to prevent decomposition and reduced lubrication effectiveness. When replacing deteriorated lubricant, ensure the main reducer is thoroughly cleaned to avoid contamination of the new oil.

Most of us in the transport business follow the repair shop's advice – rear axle gear oil should be checked and replaced every 7,000-8,000 kilometers. For trucks like mine hauling construction materials, driving on rough roads daily and overloaded, changing it every 5,000 kilometers is the safest bet. Last oil change, the mechanic said the amount of metal shavings in the oil was alarming, indicating severe gear wear. A reminder to everyone: always choose GL-5 grade 85W-90 oil, suitable for both winter and summer. When changing the oil, it's best to replace the rear axle housing bolt gasket as well, otherwise it's prone to oil leaks. If you smell burning or notice the rear axle overheating, don't hesitate – get it checked immediately.

When I first started in this field, my mentor taught me carefully: gear oil should be changed at least once a year or after driving 20,000 kilometers. But those who actually drive tricycles know it depends on the workload. For example, my water delivery truck is always climbing hills, so I need to change the oil every three months. Don’t wait until the oil turns black to replace it. If you notice metal powder in the oil, it means the wear is intensifying. Also, check if the axle shaft oil seal is leaking—many strange noises are actually caused by insufficient gear oil due to aging seals. Remember to clean the iron filings on the magnet; it’s the last line of defense for protecting the gears.

Last time the rear axle burned out and cost over two thousand to repair, now I change the oil every three months without fail. For ordinary three-wheelers, using thicker 85W-140 gear oil is better, especially for vehicles carrying loads. Focus on oil quality changes: normal oil should be clear like honey, emulsified and white indicates water ingress, and thin like water means the oil has degraded. If there's a clunking noise when shifting gears or the humming sound gets louder while driving, it's time for an immediate check. Now I change it myself—buying an oil gun is cheap, and three barrels are enough to fill the rear axle.


