<VV> Greenbriers on sand dunes

[David Houston]

Back in the late 60's I saw a Greenbrier with oversized, under-inflated tires being driven on the sand dunes of the Cape Cod National Seashore. In those days you could drive onto the sand w/o permits. VW dune buggies prevailed.
I didn't get close enough to see if the FC was modified in any way. What changes might be made to safely drive a FC over the dunes. In 1969, I had a 1967 Jeepster Commando w/ std 3 speed & V6 which did the job with air let out of the tires. Would my PG Greenbrier be able to handle sand?