2026 Grand Design Momentum 399M - 15732
For Sale in Corinth, TX.

MSRP: $196,512
Sorry this unit has no videos
Sale!
  • PRIMARY INFORMATION

  • Stock #15732
  • Year2026
  • ManufacturerGrand Design RV
  • MakeGrand Design
  • ModelMomentum
  • Floorplan399M
  • TypeToy Hauler
  • ConditionNew
  • Length44' 0"
  • VIN573FM473XTBB04988
  • MSRP$196,512.00
  • Sale Price$135,995.00
  • SPECS

  • Chassis101" Wide Body Super Chassis w/Drop-Frame Storage
  • Sleeps6
  • Water Capacity (Fresh)140 gal
  • Water Capacity (Black)52 gal
  • Water Capacity (Grey)104 gal
  • Air Conditioners3
  • A/C Spec3 X 15K BTU
  • GVWR22,500 lbs
  • Slideouts3
  • Dry Weight18,000 lbs
  • Payload Capacity4,500 lbs
  • Tow/Hitch Weight3,464 lbs

Description


  • 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 — whether you’re hauling toys or just want a big, well-laid-out rig for camping, road trips, or extended travel. Easy to live in, easy to enjoy — exactly what you want out of a modern toy hauler.

McClain's RV Superstore

5601 S. I-35 E.
Corinth, Texas


Contact McClain's RV Superstore


Features

Appliances

  • Furnace
  • Microwave
  • Refrigerator
  • Stove Top Burner
  • Water Heater

Electrical

  • Air Conditioning
  • Batteries
  • Solar Prep

Equipment

  • CO Detector
  • Fire Extinguisher
  • LED Lights
  • LP Detector
  • Propane
  • Smoke Detector
  • TV
  • TV Antenna

Exterior

  • Awning
  • Black Tank Flush
  • Detachable Power Cord
  • Enclosed Underbelly
  • Exterior Speakers
  • Heated Underbelly
  • Leveling Jacks
  • Pass Thru Storage
  • Ramp
  • Roof Vent
  • Screen Door
  • Slideout
  • Tinted Windows

Interior/Furnishings

  • Central Vacuum
  • Day/Night Shades
  • Fireplace
  • Free Standing Dinette w/Chairs
  • Island Kitchen
  • King Size Bed
  • Kitchen Sink
  • Medicine Cabinet
  • Overhead Cabinetry
  • Pantry
  • Roof Vents
  • Shower
  • Table and Chairs
  • Theater Seating
  • Toilet
  • Wardrobe(s)

Need Advice?

Join us on our popular forums at www.rvtalk.com where hundreds of RV enthusiast just like you ask questions, share opinions, and enjoy each others company - You'll be glad you did.

Our RV Destinations section will give you a starting point to plan your next journey or camping trip. Designed to provide everyone from full timers to occasional campers a complete resource, this section has links to campgrounds, resorts and local areas of interest all over the US.

Finally, our RV Insurance and RV Financing sections allow you to get quotes from the top providers.