Roger:
There is a reaction between DOT 3
and DOT 5. To switch fluids EVERY
rubber component of the system must be
changed. Hose's, cups etc.
I replaced all those items after flushing the system with denatured
alcohol and
compressed air & have been satisfied with the Dot 5 results. Others may
not be.
Jim ....... 1939 Custom Imperial Limo C24