Difference between engine oil, gear oil, axle oil and hydraulic oil and their grades?

Question

Accepted Answer

Engine oil, gear oil, axle oil, and hydraulic oil serve different purposes in a vehicle and have specific grades for optimal performance.

Engine oil is used to lubricate internal combustion engines and comes in different grades such as 5W-30 or 10W-40.
Gear oil is designed for transmissions, differentials, and transfer cases to reduce friction and wear. Common grades include 75W-90 or 80W-90.
Axle oil is specifically formulated for axles to provide lubrication and cooling. Grades like 85W-140 are commonly used for heavy-duty applications.
Hydraulic oil is used in hydraulic systems to transfer power and lubricate components. Grades like ISO 32 or ISO 46 are common for various equipment.

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