2026 Grand Design Momentum M-Class 399M

New Fifth Wheel in Ashland, Virginia, 23005

$164,495.00
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New 2026 Grand Design Momentum M-Class 399M available in Ashland, Virginia
2026 Grand Design Momentum M-Class 399M - New Fifth Wheel For Sale by General RV Center in Ashland, Virginia
2026 Momentum M-Class 399M by Grand Design from General RV Center in Ashland, Virginia
New 2026 Grand Design Momentum M-Class 399M available in Ashland, Virginia

Unit Specs

  • Stock #338373
  • Year2026
  • ManufacturerGrand Design RV
  • Make Grand Design
  • ModelMomentum M-Class
  • Floorplan399M
  • Type Fifth Wheel
  • ConditionNew
  • Length44' 0"
  • Width8' 0"
  • Height13' 0"
  • VIN573FM4735TBB04543
  • MSRP $188,573.00
  • Sale Price $164,495.00
  • Need to know your payment? Use our RV Loan Calculator!
  • Sleeps4
  • Slideouts3
  • Dry Weight19,310 lbs
Grand Design Momentum fifth wheel toy hauler 399M highlights: Front Private Bedroom Kitchen Island Hybrid Desk/Dinette Unobstructed Pass-Thru Storage Side Patio This toy hauler has all the comfort and convenience you could ask for! Once you have unloaded your toys from the 12' 6" separate garage, you can start lunch on the exterior griddle located by the side patio. There is also a 65" TV here and a 1.7 cu. ft. refrigerator to entertain guests! If the weather isn't cooperating, you can make meals in the fully equipped interior kitchen, complete with an island, pantry, pull-out countertop extension and more. An L-shaped sofa with recliners is in perfect view of the 50" TV and fireplace, and there is even a hybrid desk/dinette with windows where you can get some work done if needed. Head towards the front to freshen up in the full bath before heading to bed in the private bedroom. Here, you'll find a queen bed slide out with an optional king bed, a large closet with washer and dryer prep, plus a dresser with TV prep if you want the option to watch movies in bed! 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 fully enclosed and heated underbelly and storage area, the 5-sided aluminum cage, 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, 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!

2026 Grand Design Momentum M-Class 399M Features


2026 Grand Design Momentum M-Class 399M Specifications

General

MSRP

$174,278

Dimensions

Height

13' 6"

Height (interior)

8' 5"

Length

44' 10"

Width

8' 5"

Weights

Dry Weight

18,000 lbs

GVWR

22,500 lbs

Hitch Weight

3,464 lbs

Payload Capacity

4,500 lbs

Capacities

Refrigerator Capacity

20 cu ft

Sleep Capacity

6

Water Capacity - Black

52 gal

Water Capacity - Fresh

140 gal

Water Capacity - Grey

104 gal

Exterior

# Awnings

3

# Axles

3

# Doors

3

# Slides

3

Chassis

101" Wide Body Super Chassis w/Drop-Frame Storage

Hitch

Fifth Wheel

Rear Opening

Ramp

Electrical

# A/C

1

A/C Spec

30,000 BTU

*MFG Specs are for base unit. Certain options may change specifications listed. Please consult dealer for more details. Data is provided by a 3rd party. RVUSA.com cannot guarantee the accuracy of the data presented.

2026 Grand Design Momentum M-Class 399M Literature


Seller Info

General RV Center

12500 Harley Club Dr.
Ashland, VA 23005

Member Since 2023

See 1553 Reviews

Unit Specs

  • Stock #338373
  • Year2026
  • ManufacturerGrand Design RV
  • Make Grand Design
  • ModelMomentum M-Class
  • Floorplan399M
  • Type Fifth Wheel
  • ConditionNew
  • Length44' 0"
  • Width8' 0"
  • Height13' 0"
  • VIN573FM4735TBB04543
  • MSRP $188,573.00
  • Sale Price $164,495.00
  • Need to know your payment? Use our RV Loan Calculator!
  • Sleeps4
  • Slideouts3
  • Dry Weight19,310 lbs

Email Seller

Request More Info on this 2026 Grand Design Momentum M-Class 399M Offered for sale by General RV Center
General RV Center
General RV Center

12500 Harley Club Dr.
Ashland, VA 23005

Phone: Click to Call

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New 2026 Grand Design Momentum M-Class 399M available in Ashland, Virginia
2026 Grand Design Momentum M-Class 399M - New Fifth Wheel For Sale by General RV Center in Ashland, Virginia
2026 Momentum M-Class 399M by Grand Design from General RV Center in Ashland, Virginia
New 2026 Grand Design Momentum M-Class 399M available in Ashland, Virginia