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Home › Brands › Grand Design › Momentum › 399M

2026 Grand Design Momentum 399M

Floorplan diagram, specifications and live availability at Motor Sportsland.

Length 44' 10"Dry Weight 19170Ext Height 13' 6"Fresh Water Capacity 140Garage Size 12' 6"Black Water Capacity 52
2026 Grand Design Momentum 399M floorplan diagram

2026 Grand Design Momentum 399M specifications

Length44' 10"
Dry Weight19170
Ext Height13' 6"
Fresh Water Capacity140
Garage Size12' 6"
Black Water Capacity52
Cargo Capacity4330
Grey Water Capacity104
GVWR23500
Hitch Weight3406

Availability

Not in stock right now — we can order the 2026 Grand Design Momentum 399M for you. Call (801) 262-2921.

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← all Momentum floorplans · Call (801) 262-2921 about the 2026 Grand Design Momentum 399M.