Red Rubber Grease….let’s use the acronym RRG – has been around for decades. The reason it’s been around for so long is because the compostion of RRG is pretty basic. RRG is made from vegetable oil, a thickener and red dye. Guys from the Lexus forum mentioned many of their members used it on brakes. Since it has very limited use as a lubricant it shouldn’tbe jused anywhere on a brake caliper, the silicone rubber boot does not need lubricating, I’d like to know what folks actually use it for!