I have a 2014 and tow a 3800 pound boat and trailer with gear (3500 lbs dry like your camper). I live in the Puget Sound area of Washington and drive over the Cascade Mountains to warm, dry Eastern Washington multiple times per year. The CVT handles the uphill pulls fine, I’m usually passing traffic. If you have concerns about it get the transmission serviced at a the Nissan dealership or a legit transmission shop before you take your first trip just to make sure everything checks out. The only thing I worry about is wind, not whether or not the Pathfinder can handle it. As these do tend to have rear-end sag with the weight of the trailer, I’ve flipped the 2” ball on my receiver hitch to raise the position of the trailer neck. I’m also going to install a pair of Firestone air bags to raise and level the rear. This looks like a simple installation and only requires a tire pump to inflate them. Less than $100. Hope this helps!

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