Synthetic and "regular" fluid should be compatible, check the labels.

Did VW specify DOT-4? (I ask because I don't know).  If they specify
DOT-4, I certainly would not use DOT-3.  DOT-4 has a higher boiling
point and despite thinking of the vanagon as "small" they have a GVWR
of over 5000 lbs this is pretty heavy compared to a passenger car for
example.

Also you need to completely flush out your brake fluid with fresh
every two years.

Allan

AAG - Larry Word <word_aag@COMCAST.NET> writes:

> Ok...it appears "most" brake fluid now is synthetic, agreed?
>
> If so, and I have the old DOT 3 in my system, must I flush all that
> fluid out to get consistant synthetic-only fluid?
>
> Any can anyone tell me of a case where synthetic DOT 3 was NOT
> adequate for the job of stopping our small vans....
>
> Larry Ga.
>
> PS. I'd like to stay with what I've already got in the system,
> synthetic DOT 3 and I have a hard time believing my little daily
> driver van needs a HP, hi-temp. brake fluid so tell me how I'm wrong?
> Any case studies where DOT 3 was not adequate....
>