The purpose, features and uses of red rubber grease.

red rubber grease spoonful

Why do we need Red Rubber Grease?

Rubber without lubrication dries out, hardens, crackles and breaks. If affected by gasoline or if lubricated with petroleum-based grease, it swells, loses its shape and does not do the work as intended. When in contact with moving parts, it wears out from friction (an o-ring against a brake caliper or cylinder piston, a dust boot against a clutch plunger) and also may rupture. And, finally, during assembly, it is hard to push a piece of dry rubber into a casing and even more so to slide one rubber part onto another.

To help in all of the above situations red grease was designed, Castrol RRG being one of the best known brands. Being a vegetable oil based lubricant this grease does not harm rubber and can be used for its protection, lubrication and preservation. It can also be a great help during assembly of units containing parts made of natural or synthetic rubber and even plastic (installing bushings, for example).

Because of a unique combination of two of its qualities: natural rubber compatibility and brake fluid compatibility the main use of Red Rubber Grease is in hydraulic brake/clutch applications.

What is the main purpose of RRG?

Preserving natural rubber parts, lubricating rubber to rubber or rubber to metal contacts, helping in assembly of units containing rubber parts.

Red rubber grease uses.

Because of the qualities mentioned above Red Rubber Grease it is ideal for use in hydraulic systems, namely, hydraulic brakes and clutches or shock absorbers, pneumatic systems containing rubber parts (o-ring, seals). For this reason a sachet of the red grease comes as a standard part of quality brake/clutch and motorcycle fork oil seal and dust seal repair kits.

In contrast to regular automotive lubricants that are petroleum-based, red rubber grease is vegetable oil based (red dye is added for identification purposes) - this is the reason why it's "rubber friendly". Being that, RRG can be used where ever natural rubber is used in the car (see some applications mentioned on this site.)

Here is a comprehensive list of RRG properties:

  • Fully compatible with natural and synthetic rubbers
  • Compatible with brake fluids and some hydraulic oils.
  • Rust inhibitor (protects from oxidation and rust).
  • RRG is water resistant.
  • Hight temperarure. The grease can be used in applications with temperatures up to 210-230F. It will not melt and will not contaminate brake pads.
  • Petrol resistant. Although it will get contaminated in contact with gasoline, but still it will protect rubber parts from it.
  • High chemical and structural(mechanical) stability.
  • High resistance against water washing (will stay on after a rain, or car wash).
  • Has high wear protecting quality.

In other words, RRG can be used for lubrication where there is rubber and there is no gasoline: o-rings, non-petroleum oil and dust seals, dust boots, bushings.

Read the technical specs and MSDS of Castrol red rubber grease and also of RRG from such manufacturers as Millers Oils and Fuchs on our Tech info page.

Learn how to use rubber grease when rebulding brake calipers.

Learn how to use rubber grease when rebulding clutch master cylinder.