You *can*, but why would you want to? And it's way easier to do that if you have unlimited Express Pass and early entrance to Wizarding World, which you get by staying onsite at Portofino, Hard Rock, or Royal Pacific.
I think that most of us reading and posting on this particular forum are DVC members.
Those of us who want to do Universal *right* will use cash to stay onsite there. The benefits of onsite at Uni are worlds beyond the so-called benefits of onsite at WDW. I would gladly stay at Uni and visit WDW rather than do it the other way.
The moment Uni opens a timeshare that's like their deluxe resorts is the moment we put our DVC up for sale.
Use the cash; stay over at Uni. Stay onsite one night and you get two days of early entrance and unlimited Express Pass. Stay for 2 nights and you get 3 days worth of it.
Now, Uni hotels do charge parking fees. WDW does not (has nothing to do with DVC, but whether or not you're an onsite guest). But in this fellow DVC owner's eyes, a parking fee at Portofino is worth driving up and back I-4!