Silicone grease sells side by side with lithium grease in hardware stores and auto parts stores. But what is silicone grease used for? Here’s when to use it and why, and when to use another type. Although it may seem like grease is grease, that’s not entirely the case.
Plastic compatibility
Plastic frequently tends to be self lubricating, but under the right circumstances it can still seize up. So when you need to lubricate surfaces that involve plastic, silicone grease is the right type to use. That’s both plastic on plastic and plastic on metal connections.
This includes things like drawer slides on furniture, and sometimes computer parts, such as rails inside floppy drives, and plastic gears. Lithium grease will cause plastic to degrade over time. The silicone type provides the necessary lubrication without the danger of degrading the plastic. When a type of grease says it’s plastic compatible, that’s what it means.
If you remember nothing else from reading this, remember to use silicone grease for plastic. It will help the plastic to not wear out, and it won’t degrade the plastic unlike other types of grease.
Battery terminals and spark plug boots
Traditionally, dielectric grease, the grease we put on car battery terminals to keep them from corroding, is silicone grease. So when you need to protect the terminals on a car battery or a spark plug, you can’t go wrong with silicone grease. Just go easy on it. It doesn’t take much to protect the terminals, and it doesn’t take much more to cause problems. So be stingy and apply a nice, thin layer. It’s better to not apply enough than to apply too much.
David Farquhar is a computer security professional, entrepreneur, and author. He started his career as a part-time computer technician in 1994, worked his way up to system administrator by 1997, and has specialized in vulnerability management since 2013. He invests in real estate on the side and his hobbies include O gauge trains, baseball cards, and retro computers and video games. A University of Missouri graduate, he holds CISSP and Security+ certifications. He lives in St. Louis with his family.
Silicone grease is also safe to use on rubber parts. I have used it on rubber bushings on my car’s anti-roll bar (part of the suspension system), as well on rubber boots/seals in the braking system. Normal petroleum grease will cause rubber to swell (and often causes premature failure in braking system applications).
I learned this from Eric the Car Guy on YouTube. He’s a former Honda/Acura dealer mechanic, and a staunch believer in silicone grease for such applications.