If you are putting VW Alloy on your van (like the stock 14" alloy or the 15"
alloys that I sell from South Africa) then you do not need to change your
rear studs they are long enough.  As for the hardware you will need new lug
nuts and bolts (or just nuts if you have a syncro) because the alloy rims
have a concial seat for the hardware with a 60 degree taper.  The steel rims
have a round seat and so if you use steel hardware with the alloy rims
instead of having an even distribution of the load to the surface where the
nut meets the rim you will have a very small amount of actual contact between
the two which could cause the nuts and bolts to come loose in the future or
mess up the bolt holes.  Also you can't get as many turns out of the steel
hardware so it is not as secure.  I have kits for mounting the alloy rims
that include all the hardware for all four wheels for $50 (this is $2.50 a
nut or bolt).  Just FYI

Thanks,
Ken Wilford
John 3:16
www.vanagain.com
Phone: (856)-765-1583
Fax: (856)-327-2242