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- New
- In Stock
- Southaven RV & Marine
- GR2490
- 573FM4734TBB04792
- Trailer
- Toy Hauler
2026 Grand Design Momentum M-Class 399M
Our top-of-the-line Momentum Fifth Wheel Toy Haulers are — inside and out — our most luxurious Toy Haulers. With the comfort of a master suite and master bath, home’s now a long way from your house.
Features may include:
- Thermal Roof Design (R-40)*
- Fully Laminated Walls (R-11)*
- Triple Insulated Main Floor (R-45)*
- Triple Insulated Garage Floor (R-40)*
- 1.5" Insulated Baggage Doors
- Vented Attic
- Insulated Gooseneck
- Rail-Tite Underbelly Seal
- New
- GR2490
- 2026
- Grand Design
- Momentum M-Class 399M
- Trailer
- Toy Hauler
- Grand Design Momentum
- 573FM4734TBB04792
- No
- 13' 6" | (w/opt. AC): 13' 6"
- 44' 10"
- 8' 5"
- 8' 5"
- Standard Bed: 60 X 80 Queen Bed | Standard Bunk: 30 X 80 | Shower: 48 X 30
- 12' 6"
- 14' 9' 12'
- 3,464 lbs.
- 18,000 lbs.
- 22,500 lbs.
- 140 gal.
- 104 gal.
- 52 gal.
- 60 gal
- 9
- 60 lbs
- On-Demand
- 20 cu. ft.
- Propane Tanks: 2 | Construction Type: Aluminum Cage | Slide Room R-Value: R-11 | Garage R-Value: R-40 | Slides: 3 | Awnings: 3
- R-45
- R-11
- R-40
- 35,000 BTU
- 30,000 BTU
- 3
- 17.50 in.
- ST215/75R17.5 LRH
Recommendations
Advertised pricing excludes applicable taxes title and licensing, dealer set up, destination, reconditioning and are subject to change without notice. Pricing may exclude any added parts, accessories or installation unless otherwise noted. Sale prices include all applicable offers. Not all options listed available on pre-owned models. Contact dealer for details.