After putting 100 miles since a tire change on my 2018 Crosstrail Sport Disc I can wholeheartedly encourage others to put some larger tires on their CTs. I took off the OEM 700cX38c back in August and bent on some 2" wide Schwalbe Marathon 700Cx50C Wire Endurance Green Guard tires. These tires have transformed the ride and steering of the bike. They fit fine on the OEM 700cx28c rims and they don't rub or interfere with any part of the frame. They tame small bumps and smooth out larger road divots. Plus, they grip so much better that I can take turns much faster and more confidently than before.
Now, the only drawback I can see is a bit of increased weight but it's not a massive increase at all.
This makes two "must have" changes to the original Crosstrail - change the fork to the Rockshox Paragon Gold and the tires to Schwalbe Marathon 700Cx50C Wire Endurance Green Guard tires. You won't be sorry.
Here's a photo showing the tire and the fit with the frame.
