Greases

Grease is oil held in a thickener so it stays where it is applied. That makes it the lubricant of choice for wheel bearings, chassis joints, bushings, open gears and any component that cannot be fed by an oil circulation system. Choosing the right grease depends on consistency, thickener, operating temperature and load.

NLGI grade. The NLGI number describes consistency. NLGI 0 and 1 are soft and flow easily, useful for centralised lubrication systems and cold conditions. NLGI 2 is the common general-purpose grade for bearings and chassis points. NLGI 3 is firmer and often chosen for vertical shafts or worn, loose bearings.

Thickener. Lithium and lithium-complex greases are widely used for general automotive work. Calcium and calcium-sulphonate greases resist water well, which is why they are popular for marine applications. Polyurea and other synthetic thickeners are often used in sealed-for-life bearings. Mixing incompatible thickeners can soften the grease and cause leakage, so clean out old grease when changing type.

EP additives. Extreme-pressure (EP) greases contain additives that protect surfaces under shock loads and heavy pressure, for example in heavily loaded joints or slow, high-torque machinery.

Environmental grades. Biodegradable greases are formulated for equipment used near water or in sensitive areas. Compare the details in each product description, apply with a grease gun until fresh grease appears at the seal, and avoid over-filling sealed bearings.