Yes, your 2318g should had the roof rack. I was considering the purchase of a 2318g, 2516g. and the 2716g. All had roof racks.
2318g pics
Now the 2318ESP doesn't have roof racks because there's a solar panel in the area instead.
2318ESP pics
However, to add any, I would think you would need support members in the roof to attach the racks to. Otherwise you are just attaching to Styrofoam and thin fiberglass sheeting.
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2019 Ford F150 Race Red XLT Sport, CC, 4WD, 145" WB, 3.5L Ecoboost, 10 speed, 3.55 Locking Axle, 1830# Payload, 12,700# Tow Rating, pulling a
2020 Rockwood Premier 2716G Pop Up, with a 14' box. Go through
Indiana Dunes NP 5X/week! Previously had
2012 Jayco Jay Flight 26BH and
2008 Jayco Jay Flight 19BH Travel Trailers. Also previously had
2007 Starcraft 2406 Pop Up with 12' box and bathroom
, Previously had 2005 Rockwood 2290 Pop Up with 12' box and porta potty cabinet.
Trucks and Trailers.