Just to be sure draw off a small amount of fluid and put into a container with 1/2 " of water. If the two mix it is Dot 3, 4 or 5.1 glycol based (all will mix together). If the water and fluid don't mix it will be silicone based Dot5 (and will not mix with the other fluids).
If glycol I, too, would go for dot4 and here's a useful link..........https://blog.amsoil.com/dot-3-and-dot-4-brake-fluid-whats-the-difference/
