What is the Difference Between Lubricating Oil and Engine Oil?

[MacEli]

Here are the specific differences between lubricating oil and engine oil: 1. Scope: Engine oil is a type of lubricating oil, but not all lubricating oils are engine oil. Engine oil is one category within lubricating oils. 2. Definition: Any oil that lubricates mechanical components can be called lubricating oil, whereas engine oil specifically refers to lubricants used in engines. 3. Function: Lubricating oil is a type of fluid used to reduce friction in machinery and equipment, such as gear oil or anti-wear hydraulic oil. Engine oil serves to lubricate, cool, clean, seal, cushion shocks, and prevent rust and corrosion in engines.

[McAsher]

At first, I couldn't quite tell the difference between lubricating oil and engine oil, but later I learned that engine oil specifically refers to the lubricating oil used in engines. Inside the engine, where temperatures and pressures are high, engine oil must be able to resist wear and corrosion, and also clean carbon deposits. The viscosity grades we often hear about, like 5W-30, are for engine oil. Lubricating oil, on the other hand, has a broader scope and includes transmission fluid, brake fluid, and power steering fluid. Once, while repairing my car, I almost added the wrong type—turns out transmission fluid, although also a lubricant, is much thinner than engine oil, and using the wrong one can damage the transmission. So during maintenance, always check the labels carefully: use proper engine oil for the engine and the corresponding lubricating oil for other parts—never mix them up.

[DanteLynn]

After a decade in auto repair, I've seen many car owners confuse these two concepts. Simply put, engine oil is the lubricant specifically for engines, designed to withstand the high temperatures and friction from piston movement. That's why its base oil and additives are specially formulated - for instance, zinc-containing formulas protect camshafts. Lubricant is the umbrella term covering various fluids like brake hydraulic oil and greases. Here's a practical example: gearbox lubricants are typically thicker than engine oil. Pouring regular lubricant into an engine would cause oil film breakdown under high temperatures, leading to cylinder scoring. Remember: all engine oils are lubricants, but not all lubricants are engine oils.

[AshlynRose]

I used to wonder why the maintenance list at 4S shops separately listed lubricating oil and engine oil, but now I understand. Engine oil specifically refers to motor oil, like full synthetic and semi-synthetic oils, which are designed for engines and require frequent changes. Lubricating oil includes types like differential oil that are lifetime fill, and even bicycle chain oil counts. The key difference is that engine oil must adapt to the combustion environment of the engine and deal with gasoline contamination, which other lubricants don’t need to consider. During maintenance, be extra careful: using the wrong lubricant in the power steering system might cause squeaking, but using the wrong oil in the engine could lead to complete failure.