STP All Purpose Industrial Grease Review
Multipurpose grease
STP all-purpose grease is a consumer tub of lubricating grease sold for shop and home use. Multipurpose, in the grease trade, usually means an NLGI 2 grease with a lithium or lithium-complex thickener and a mineral or synthetic oil. It is the grease in a cartridge gun for chassis fittings, hinges, latches, and light machinery. The photograph on this page is that kind of tub. The name on the tub is a brand. The useful description is the thickener and the NLGI grade printed on the back.
NLGI 2 is stiff enough to stay in a fitting and soft enough to pump by hand. A lower number is softer and is used in cold weather or in central lube systems. A higher number is harder and is used where the grease must not sling off. Additives for extreme pressure help sliding contacts such as ball joints. They are not proof that the grease belongs in a high-speed wheel bearing or in an electric-motor bearing. Those jobs name their own products.
Multipurpose grease is not a seal grease. Rubber O-rings, plastic bushings, and many electrical connectors want a silicone grease, because a petroleum oil can swell the rubber or collect dust in a connector. Multipurpose grease is also not food grade unless the label says so. A kitchen must not grease a mixer shaft that touches food with a chassis grease. And it is not choice white grease. Choice white grease is a rendered pork fat sold by the hundredweight. White lithium grease is the lubricant. The words look alike and the products are unrelated.
Do not mix this grease into a bearing already packed with polyurea, clay, or calcium sulfonate. The soaps can fight, and the bearing loses the film it had. If the old grease is unknown, clean the part. Do not pump grease into a sealed bearing that has no fitting. The seal will blow, and the extra grease becomes a dirt magnet. A fitting that will not take grease is often blocked, not empty. Forcing it pushes grease past a seal.
GREASE.ORG uses this page as a reference for what a multipurpose tub is. It is not a review score and it is not a price. For a plant bearing, read the machine manual and match thickener, oil, and NLGI grade. For a grease trap or a drum of used cooking oil, you are in a different business. Those are kitchen wastes, not lubricating greases, and they are handled on the cooking-oil and trap pages.
A good shop habit is one gun, one grease, and a label on the gun. The next job then starts from a known thickener instead of whatever cartridge was left in the handle.
