One should carry Canadian currency, at least enough to fill your truck with fuel. It isn't uncommon for the networks to fail, for various reasons, which means no one's credit or debit card will work.
I've been in Whitehorse on several occasions when the machines were down and it was cash only, so I also carry enough to grocery shop when I'm in the city.
One trip out, Toad River on the Alaska Hwy in northern B.C. had no phone or internet working. To get fuel, it was cash only or wait for the systems to get back online. We had enough cash to fill up and carry on.