2025 Grand Design Momentum 399TH

Vehicle Photo
  • MSRP: $170,577
Stock #: 21161920
Knoxville (Strawberry Plains), TN
  • Available
  • New
  • Class: Fifth Wheel
  • Length: 43 ft 1in
  • Slides: 3
  • Dry Weight: 15,900
  • Sleeps: 5

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  • Bath and a Half
  • Front Bedroom
  • Kitchen Island
  • Loft
  • Toy Hauler
  • Two Entry/Exit Doors
Floorplan
  • Available Beds Queen
  • Exterior Height 13 ft 6in
  • Exterior Width 8 ft 5in
  • Interior Height 8 ft 5in
  • Garage Size 13 ft
  • Pin Weight 3,400 lbs
  • Gross Weight 22,500 lbs
  • Dry Weight 15,900 lbs
  • Fuel Capacity 60 gal
  • Tire Size 17.5"
  • Axle Count 3
  • Fresh Water Capacity 140 gal
  • Grey Water Capacity 104 gal
  • Black Water Capacity 104 gal
  • Furnace BTU 40,000
  • Refrigerator Type 12V Stainless Steel
  • Refrigerator Size 20
  • Cooktop Burners 3
  • Shower Size 48" x 30"
  • Shower Type Shower w/Seat
  • Number of Awnings 2
  • Electrical Service 50 amps
  • Washer/Dryer Available Yes
  • TV Info LR 49" LED TV, BR LED TV, Garage 32" LED TV
Grand Design Momentum fifth wheel toy hauler 399TH highlights:
  • Fold-Down Side Patio
  • 13' Garage
  • Bath and a Half
  • Dual Entry
  • Smart Sink
  • Fireplace

 

Get ready for a lot of fun when you head out to the off-road park, a special event, or a long trip with your toys! You will love the garage with the Fast Ramp rear ramp door, the Ram-Air garage vents on both sides, the 2,500 lb. rated flush-mount tie-downs and the protective diamond plate on the garage sidewalls. This area can become a bedroom or an extra living area if you want to add Happi-Jac rollover sofas/table with a top bed option, plus you will already have a half bath for convenience, an overhead loft bed plus a flip-up pet dish for your furry friends. The living and kitchen area is spacious with dual slides and a kitchen island with bar stools, a free standing dinette and theatre seating. The fold-down side patio offers a great place to relax outdoors above ground, and there are many more features to enjoy plus several options to customize your fifth wheel. 

 

The Momentum fifth wheel toy haulers by Grand Design are built for four seasons of travel with your off-road toys and include luxurious accommodations throughout for extreme living! Each is constructed to a superior standard with the thermal roof design, the full-laminated walls, and the triple insulated garage floor. The MORryde CRE3000 suspension system and rubber pin box, plus the upgraded axle hangers provide the performance and smooth towing you desire, while the interior offers luxury such as color changing LED accent lighting, raised panel hardwood cabinet doors with hidden hinges, and a central vacuum system. Each toy hauler also includes four packages, including the Garage Package with Tuff-Ply gas and oil resistant flooring, the Weather-Tek Package with a Stealth AC System, and the Interior Luxury Package with solid surface countertops!

†Lazydays strives to ensure the accuracy of the information provided on this website. However, actual products, programs and services may differ materially from those on this site. Lazydays is not responsible for errors made in stated pricing. Specifications and availability subject to change without notice. Sale price includes all manufacturer discounts and rebates. All prices listed on this site exclude tax, tags and title fees. Applicable government fees, state taxes, dealer fees and emissions testing charges will be added to comply with state vehicle codes. Freight and prep costs are additional and vary by state. Contact Lazydays for complete details.

*90 Days – Payments can be deferred for 90 days with approved credit. Interest accrues from contract date. Financing terms subject to lender approval. Not valid with other offers. Actual products, programs and services may differ materially from those on this site. Lazydays is not responsible for errors made in stated pricing. Specifications and availability subject to change without notice. Document fees vary by location. See dealership for complete details.

**Lazydays believes the specifications on this site supplied by the manufacturer to be correct at the time posted. However, specifications, standard equipment, model availability, options, fabrics, and colors are subject to change without notice. Some equipment may be unavailable when a vehicle is built. Some vehicles are pictured with options, which may be available at extra cost or may not be available on some models. You should verify the equipment that is on all vehicles. If a new vehicle shown on this website is subject to an open safety recall, Lazydays cannot deliver the vehicle to you until the recall repair is completed. This is a requirement of federal law.