There is a wide variety of cooking oils from plant sources such as olive oil, palm oil, soybean oil, canola oil (rapeseed oil), corn oil, peanut oil and other vegetable oils, as well as animal-based oils like butter and lard.
We called a couple of the brake fluid companies and the answer was two to five years is a safe number for an unopened container. Wilwoodâs tech line claims that if the container is sealed, they feel it has an unlimited shelf life, but I would consider five years to be the limit.
How often is it advisable to do a full brake fluid flush? I've had my car for 13 months now. I'm planning on upgrading to the 991S front brakes in a couple of months and was thinking I might as well just do a full brake fluid flush then.