This Resource Centre provides general guidance only. Always follow the equipment manufacturer’s instructions, the product technical data sheet and your site’s safe system of work. Isolate stored energy before maintenance. For safety-critical, regulated or uncertain applications, ask a competent engineer or the product manufacturer to confirm the specification.
Grease or oil: which should you use?
Both grease and oil create a lubricating film and help control friction and wear. The application determines which method is more practical.
When grease is often suitable
Grease tends to stay in place, can help exclude contaminants and requires a relatively simple housing. It is widely used in rolling bearings, pins and joints where relubrication intervals are manageable.
Grease may be preferred where:
- leakage must be minimised;
- the component is difficult to seal for oil;
- speed and temperature are within the grease capability;
- the lubricant can also support sealing against dirt or moisture.
When oil is often suitable
Oil can circulate, carry heat away, reach multiple points and be filtered. It is often selected for higher speed or temperature, gear systems, engines and arrangements where condition monitoring or cooling is important.
Oil may be preferred where:
- heat removal is required;
- very frequent grease replenishment would otherwise be needed;
- components share a circulating lubrication system;
- filtration and water separation are important.
The decision factors
Check:
- component and manufacturer specification;
- load and speed;
- normal, start-up and peak temperatures;
- base-oil viscosity requirement;
- exposure to water, dust, chemicals or food;
- seal compatibility;
- relubrication access;
- risk of mixing with an existing product.
Do not convert from grease to oil, or from one product family to another, simply because the alternative is available. Confirm the housing, seals, feed method and drain path are suitable.
Need help sourcing the item?
Send the manufacturer, reference, photographs and operating details.