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2026 GRAND DESIGN MOMENTUM M-CLASS 399M
Rv TypeToy Hauler
Length44 ft
Fuel TypeNONE
Mileage1 mi
Description
2026 Grand Design Momentum 399M,
If you want a toy hauler that doesn t feel like a toy hauler meaning it lives comfortably inside whether you re hauling toys or not the 2026 Grand Design Momentum 399M delivers exactly that. The rear garage is spacious enough for quads, bikes, or gear with real tie-downs and a proper ramp, but once you re parked and set up, the interior feels like a real home on wheels.
The dual slide-outs make a huge difference with them out, the kitchen and living area feel wide, open, and easy to walk around in instead of cramped. The kitchen itself is laid out thoughtfully with an island that gives you serious prep space, a big fridge, and storage that actually works. You re not juggling pots and pans in every nook and cranny you ve got room to cook.
The living area has comfortable seating theater seats and a sofa you ll actually use with a good entertainment setup, so relaxing after a long day doesn t feel like an afterthought. Up front, the private bedroom gives you a real bed and plenty of storage, and the bathroom s layout is practical with a good-sized shower and useful circulation.
Tank capacities and utility hookups are sized for extended stays no stressing about hookups after a night or two. Outside, the power awning with LED lighting makes the campsite area feel like an extension of the interior, and the exterior storage bays are deep enough for chairs, tools, grills, and whatever gear you bring along.
Bottom line: the Momentum 399M is comfortable, practical, and built for real adventure w
- Spacious rear garage toy hauler room for quads, bikes, side-by-sides, or gear
- Side patio with outside kitchen and entertainment
- Two large slide-outs open the living/kitchen area wide
- Front bedroom with privacy and solid storage
- Full galley kitchen with island, big fridge, and real prep space
- Comfortable living area with theater seating and sofa
- Large bathroom with separate shower and good circulation
- Excellent tank capacities and utility setup for longer trips
- Built solid with Grand Design s everyday-use quality
- Power awning with LED lighting and ample exterior storage
If you want a toy hauler that doesn t feel like a toy hauler meaning it lives comfortably inside whether you re hauling toys or not the 2026 Grand Design Momentum 399M delivers exactly that. The rear garage is spacious enough for quads, bikes, or gear with real tie-downs and a proper ramp, but once you re parked and set up, the interior feels like a real home on wheels.
The dual slide-outs make a huge difference with them out, the kitchen and living area feel wide, open, and easy to walk around in instead of cramped. The kitchen itself is laid out thoughtfully with an island that gives you serious prep space, a big fridge, and storage that actually works. You re not juggling pots and pans in every nook and cranny you ve got room to cook.
The living area has comfortable seating theater seats and a sofa you ll actually use with a good entertainment setup, so relaxing after a long day doesn t feel like an afterthought. Up front, the private bedroom gives you a real bed and plenty of storage, and the bathroom s layout is practical with a good-sized shower and useful circulation.
Tank capacities and utility hookups are sized for extended stays no stressing about hookups after a night or two. Outside, the power awning with LED lighting makes the campsite area feel like an extension of the interior, and the exterior storage bays are deep enough for chairs, tools, grills, and whatever gear you bring along.
Bottom line: the Momentum 399M is comfortable, practical, and built for real adventure w
RV details
Type
Toy Hauler
Condition
New
Length
44 ft
GVWR
22,500 lbs
Odometer
1 mi
Slide-outs
3
Sleeping capacity
6
Air conditioners
3
Water capacity
140 gal
Floor plan
MOMENTUM M-CLASS
Fuel type
NONE
Dealer stock ID
15732
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