They are NOT interchangeable. They use different pads and calipers too.
1985 is a transition year and some parts are early type , some late.

80-85 ATE brand caliper
86+   Girling caliper

Mark

"Michael S. Nichols" wrote:
>
> Hello from Atlanta, Ga.  A Canadian non-list member has these questions:  Are early '80's and later '80's Vanagon rotors interchangeable?  How do they differ?  I say not interchangeable, as they have different part numbers and applications.  Thanks!
>
> Regards,
>
> Mike and Christina Nichols
> 2--'81's