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.
Most manufactuerers say the automatic transmission fluid will last over 100,000 miles with average use. But severe service rquires fluid changes every two years or 24,000 miles. Severe service can mean extended high speed driving, trailer towing, or just driving normally in cold weather. Some manufactureres (like Subaru) state that under severe  conditions you should change the AT fluid and filter every 15,000 miles. If the fluid is bright red and smells sweet, it is pobably still usable. If the fluid color is dark red or brown and smells burnt, change it.