Now, we don't pretend to be chemists, but we did stay in a Holiday Inn Express last night soooo...

Per Wikipedia, "A fluoroelastomer is a special purpose fluorocarbon-based synthetic rubber. It has wide chemical resistance and superior performance, especially in high temperature application in different media." Basically, this is what you want when it comes to engine crankshaft seals (rear main seals), push rod tube seals, and more. But how exactly is it different from Viton, which is what everyone says is you should get? Well - it's not. Viton is a DuPont brand-name for their line of fluoroelastomers. In fact, unless the seal manufacturer has specifically bought and licensed Viton from DuPont, then they are actually using a fluoroelastomer from a different rubber manufacturer.

Now, we've had lots of people who have argued that a certain seal is or isn't viton because it is or isn't brown. In actuality, you can get Viton and non-brand name fluoroelastomers in black, brown, and green - the color difference is due to a slightly different chemical additive which will change some of it's properties but in the end they are all still excellent to use as seals in a VW engine.

Is our info wrong? Please tell us!