2024 Grand Design Momentum 399TH

About the 2024 Grand Design Momentum 399TH

Work hard, play harder. That is the philosophy behind the 2024 Grand Design Momentum 399TH by Grand Design, a 2024 toy hauler that refuses to make you choose between bringing your toys and traveling in comfort.

At 28.0 feet long, 8.0-foot width and standing 12.5 feet tall, the 2024 Grand Design Momentum 399TH has a dry weight of 8,300 lbs, with a GVWR of 11,900 lbs, offering 3,600 pounds for gear and supplies.

With capacity for 9 people to sleep, this is a true family hauler. The 2024 Grand Design Momentum 399TH arranges its sleeping areas across multiple zones, so parents can enjoy separation from the kids at bedtime while everyone shares the common living space during waking hours.

For extended stays away from hookups, the 2024 Grand Design Momentum 399TH comes equipped with a generous 68-gallon fresh water supply, 70 gallons of gray water holding, a 50-gallon black water tank. For electrical needs, the unit provides 200 watts of factory-installed solar, 150 amp-hours of battery storage, a 2500-watt inverter for household AC power. A 15,000 BTU air conditioner keeps things cool in summer heat, and 25,000 BTU of furnace output tackles chilly evenings. The kitchen features a Compressor 12V refrigerator for keeping provisions cold. Outside, a 15.5-foot power awning provides welcome shade for outdoor dining and relaxation.

At 8,300 pounds dry, the 2024 Grand Design Momentum 399TH requires a capable tow vehicle. The hitch weight comes in at 1,080 lbs, an important factor for matching to your truck. Make sure your tow vehicle is rated for the 11,900-lb GVWR when fully loaded with gear and water.

The 2024 Grand Design Momentum 399TH carries an MSRP of $61,000, positioning it squarely in the mid-range of the Toy Hauler market where competition is fierce and buyers expect solid value. Large families and groups will find the 2024 Grand Design Momentum 399TH particularly appealing, with enough sleeping positions to handle a full crew without anyone being relegated to a tent or air mattress.

For 2024, the 2024 Grand Design Momentum 399TH continues to demonstrate why Grand Design remains a respected name in the RV industry. It delivers a compelling combination of comfort, capability, and craftsmanship that holds up under real-world scrutiny.

For the motorsport enthusiast who loves camping, the 2024 Grand Design Momentum 399TH provides the perfect fusion of garage space and residential comfort.

The rear garage area features a spring-assisted ramp door, tie-down points, and 48-gallon onboard fuel station. When not hauling toys, the garage converts to additional living space with a fold-down sofa and optional happi-jack bed system. The main living area includes 0 slide-out(s) and sleeps 9 total.

The 25,000 BTU furnace and 15,000 BTU AC system provide year-round climate control. Starting at $61,000, the 2024 Grand Design Momentum 399TH is competitively priced for a toy hauler of this capability and quality.