2027 Grand Design Momentum G-Class21G

The 21G is the smallest way into a G-Class garage, and it is a genuine toy hauler rather than a trailer with a ramp: a full-sized rear ramp door, a flat garage floor with no wheel wells, rear-ramp loading lights with a back-up function, 2,500-pound tie-downs anchored into the chassis and a 30-gallon fuel station with interior and exterior gauges — all standard across the G-Class travel-trailer roster. At twenty-six feet eleven inches on one slide, it is the only single-slide plan of the seven. Laminated aluminum walls at R-7 sit under a 5-inch radius wood-framed R-40 roof with a double-insulated front cap, and the underbelly is heated and enclosed with suspended tanks.

Grand Design publishes 11,000 pounds of GVWR against 7,280 dry, so the payload is 3,720 pounds — more than the entry Momentum fifth wheel's 3,090, in a trailer half its weight. The dry tongue is 1,056 pounds, which is the number to think hardest about: it is a comfortable half-ton figure at rest, but a toy hauler's tongue weight climbs with everything ahead of the axles, and an 11,000-pound loaded trailer will not stay at 1,056. Weigh it loaded and read your vehicle's door-jamb placard before you commit to a half-ton.

Momentum is Grand Design's toy-hauler family, and it spans four rosters across both tow types. The full-size Momentum fifth wheel is the flagship — a 101-inch wide-body coach on MORryde independent suspension with disc brakes, carrying a 60-gallon dual fuel station. The Momentum G-Class fifth wheel sits below it on MORryde CRE3000 suspension and a Rotoflex pin box with a 30-gallon fuel station, and the G-Class travel trailer puts that same garage behind a bumper pull. The Momentum MAV is the compact end — the lightest and cheapest way into a Momentum garage, and the one roster with no fuel station at all. The 21G on this page is highlighted; each other profiled plan links to its own page. The full MY2027 catalogue runs to 28 floorplans across the four rosters; eight are profiled in depth here and the rest are catalogued on the line hub with their weights.

A full 90-gallon fresh tank is about 751 lb of water (water counts as cargo: 49 CFR 571.120 S10.4.2), 20% of the 21G’s 3,720 lb cargo capacity, leaving 2,969 lb (495 lb per rated berth). Across 4 Momentum travel-trailer floorplans the water share runs 17% to 28%, and 1 gives up more than this one. Nearest on that share: Momentum 30G at 19% and Momentum 28MAV at 28%. Your own unit’s figure is on the label inside its entry door (49 CFR 571.120 S10.4.3).

Closest sibling: the Momentum 28MAV, nearest on the published figures. It differs on 5 of the 9 fields both publish (this plan first): length 26 ft 11 in vs 33 ft 11 in; dry weight 7,280 lb vs 8,300 lb; cargo capacity 3,720 lb vs 2,700 lb; dry hitch weight 1,056 lb vs 1,200 lb; black tank 39 gal vs 37 gal. They match on sleeps, GVWR, fresh tank and grey tank.

Either side of it by GVWR: Momentum 17MAV is 1,050 lb lighter (9,950 lb GVWR); Momentum 28MAV matches it at 11,000 lb GVWR.

All 8 Momentum floorplans: Momentum line hub.

Against the 21G: the Eagle 320FBOK is 11 ft longer; the Outback 340BH is 12 ft longer and sleeps 4 more.

16 of the 18 fields this catalogue tracks are published for the 21G. Not published: axle count, tire specification.

Sourcing rules: methodology.