Brake fluid - DOT 3 or 4???

It's great stuff. Been running it in my daily's for over a decade. Swapped it into my 3rd gen when I put the extended brake lines in. Was really weird to replace 1000 mile old brake fluid lol.

 

But DOT5.1 is fine.

My VW based beach buggy runs DOT5 brake fluid. It's always purple in color to help identify it. I replaced all rubber parts and flushed all the hard lines out with the system open to make the switch. It does not mix with DOT3, DOT4, or DOT5.1 brake fluid. I placed a sticker next to the master cylinder reservoir that states:

Warning:
Brake system is filled
with SILICONE brake
fluid spec MIL-B-46176
DOT 5 and conforms to
Federal Motor Vehicle
Safety Standard # 116​

 

...