Unlock Best Price!

New 2026 Grand Design Momentum 399M

Toy Hauler Fifth Wheel

Stock #21175561

Tucson AZ

Relax on the L-shaped sofa with recliners while watching the 50" TV and enjoying the fireplace.

1 of 46

+46

SALE PRICE: $149,995
MSRP: $191,444
You Save: $41,449

Payments From: $1,003 /mo.

45ft long
19,170 lbs
Sleeps 4

3 slides
Kitchen Island

Two Entry/Exit Doors

See All Specs

Specifications

Sleeps	4	Slides	3
Length	44 ft 10 in	Ext Width	8 ft 5 in
Ext Height	13 ft 6 in	Int Height	8 ft 5 in
Hitch Weight	3406 lbs	GVWR	23500 lbs
Dry Weight	19170 lbs	Fresh Water Capacity	140 gals
Grey Water Capacity	104 gals	Black Water Capacity	52 gals
Tire Size	17.5"	Furnace BTU	35000 btu
Fuel Capacity	60 gals	Available Beds	Queen
Refrigerator Type	12V Stainless Steel	Refrigerator Size	20 cu ft
Cooktop Burners	3	Number of Awnings	3
Axle Weight	7000 lbs	Garage Size	12 ft 6 in
LP Tank Capacity	30 lbs	Water Heater Type	On Demand
AC BTU	30000 btu	TV Info	LR 50" LED TV, Garage 32" LED TV, Patio 65" TV
Awning Info	9', 12', 14' Power w/LED Lights	Axle Count	3
Washer/Dryer Available	Yes	Number of LP Tanks	2
Shower Type	Shower w/Seat	Electrical Service	50 amp
VIN	573FM4731TBB04622

Description

"This is the manufacturer's minimum allowed advertised price, contact us today for your unbeatable personalized quote."

NEW 2026 Grand Design Momentum 399M Fifth Wheel Toy Hauler Highlights:

Front Private Bedroom
Kitchen Island
Hybrid Desk/Dinette
Unobstructed Pass-Thru Storage
Side Patio

Adventure meets comfort in the 2026 Grand Design Momentum 399M, a fifth wheel toy hauler designed for off-road enthusiasts who want all the conveniences of home. The 12' 6" separate garage provides ample space for your ATVs, motorcycles, or other toys, and you can entertain outdoors with the side patio, complete with a 65" TV, 1.7 cu. ft. refrigerator, and exterior griddle. Optional Liftsuite system and underside lighting allow extra sleeping space or ambiance in the garage.

Inside, the fully equipped kitchen features a kitchen island, pantry, pull-out countertop extension, and plenty of prep space. Relax on the L-shaped sofa with recliners while watching the 50" TV and enjoying the fireplace. Need to get some work done on the road? The hybrid desk/dinette with windows makes it easy to stay connected. The full bathroom is conveniently located near the front private bedroom, which offers a queen bed slide (optional king), large closet with washer/dryer prep, dresser with TV prep, and comfortable space to unwind after a day of adventure.

Built for four-season travel, the Momentum toy haulers include a fully enclosed and heated underbelly, 5-sided aluminum cage construction, and triple insulated garage floor for extreme weather protection. The MORryde CRE3000 suspension system and upgraded axle hangers provide smooth towing, while interior luxuries include color-changing LED accent lighting, hardwood cabinet doors with hidden hinges, and a central vacuum system. Four included packages—Garage Package with Tuff-Ply flooring, Weather-Tek Package with Stealth AC, and Interior Luxury Package with solid surface countertops—ensure your travels are comfortable, stylish, and functional.

Why Buy from Campers Inn RV Tucson? Campers Inn RV Tucson offers the largest selection of Momentum toy haulers, transparent pricing, and a team of experts ready to help you find the perfect RV for your adventures. From your first step on the lot to years of service, your experience will be seamless, fun, and worry-free.

Inventory/Stock Images may be shown. Colors and specifications may vary. Call our AMAZING TEAM for details.

Features

Standard Features (2026)

Exterior

Keyed Alike™ Ramp Door Latches
2nd Patio Awning w/ LED Lights
3rd Awning w/ LED Lights
Exterior Color Changing LED Accent Lighting
High-Gloss Gel Coat Exterior Sidewalls
Door Side Exterior Spray Port
Frameless Tinted Windows
Walk-On Roof
17.5" Spare Tire (Undermount)
MORryde Strut Assist Entry Step
Slam-Latch Baggage Doors
Mo Secure
Gen III 3 Seasons Doors (Opt)

Construction

101" Wide Body Construction
5-Side Aluminum Cage Construction
Fully Enclosed and Heated, Underbelly and Storage Area

Running Gear

Upgraded Axle Hangers
Heavy Duty H-Rated Tires
Heavy Duty 7,000 lb. Axles with ABS Brakes
17.5" H-Rated Aluminum Wheels
MORryde® Independent Suspension 2.0

Frame & Chassis

6-Point Hydraulic Leveling System
MORryde® Pin Box
101" Wide Body Super Chassis w/Drop-Frame Storage

Interior

Interior Color Changing LED Accent Lighting
Hardwood Cabinet Doors w/Hidden Hinges
Recliner Sofa w/Adjustable Headrest or Flip Down Cupholders
Central Vacuum System w/ Tools and Dust Pan
Plywood Drawer Bottoms

Kitchen

Microwave
Professional Grade Stainless Steel Cooktop
12-Volt High Power MaxxAir w/Rain Sensor
Window Behind Range
Kitchen Barstools w/ Extended Countertops
Smart Sink w/Removable Cutting Board, Produce Strainer and Glass Rinser

Electrical

Solar Prep (10-gauge wiring with universal MC4 connectors)
75 Amp Converter
12V Battery Disconnect

HVAC

12V High Power Fan (Kitchen)
35k BTU High-Capacity Furnace
Fireplace w/ 5,000 BTU Electric Heater
StealthAC Smart AC System
Attic Vent
High-Capacity Heat Ducts

Plumbing

Exterior Spray Port (Door Side)
12V Tank Heaters
Sewer Hose Storage Area
Whole House Water Filtration System
All-In-One Enclosed and Heated Utility Center

Bedroom

Under Bed Storage Area
Individually Switched Reading Lights Over Bed
Bedside 110-Volt & USB Outlets
Window Above Master Bed Headboard
60" X 80" Queen Bed Pillow Top Bed Mattress

Bathroom

Skylight Above Shower
Porcelain Toilet
Medicine Cabinet w/Mirrored Door (N/A 410TH)
Undermount Lav Sink
One-Piece Fiberglass Shower w/Glass Door & Teak Bench Seat

Appliance

Fireplace with Electric Heater
Stainless Steel 20 Cu. Ft. Refrigerator
30" Over-The-Range Microwave

Electronics

OneControl™ System
Back-Up Camera Prep
Exterior Cable/SAT Plug-In
LED Smart TV in Living Area
LED TV in Bedroom
Rockford Fosgate Stereo Entertainment System w/HDMI and App Controls
Exterior Speakers
No-Crank Digital TV Antenna w/Booster
LED TV in Garage
OmniConnect On-Board WiFi Ready

Packages

Exterior Package

Satellite TV Prep
MORryde Strut Assist Entry Step
Aluminum Quad Entry Steps - Garage Entry
7,000 lb. Axles w/Self Adjusting Brakes, Wet Bolts and Bronze Bushings
17” Aluminum Wheels (120PSI Rated)
Cooper Tires® 17.5" All-Steel H-Rated Tires
Slam-Latch Baggage Doors
Frameless Tinted Windows
Exterior Security Lights
Power Patio Awning w/LED Lighting
Folding Roof Ladder
White Gel Coat Fiberglass Front Cap
12V Battery Disconnect
All-In-One Exterior Utility Center
50 Amp Service
Converter
Enclosed Fuel Station w/ Dual Fuel Tank
Partial Paint Gel Coat Fiberglass Front Cap

Luxury Interior Package

49" Class LED TV in Living Area
Stereo Entertainment System w/Bluetooth and App Based Controls in Living Area
Washer/Dryer Prep
On Demand Water Heater
Roller Shade Window Coverings (Main Living Area and Bedroom)
Recessed LED Puck Lighting
Solid Surface Countertops w/ Sink Covers
Stainless Steel Undermount Kitchen Sink
Chef Inspired Range & Oven w/ Cover
Kitchen Pantry w/ LED Light Strip
Garage Control Panel

Garage package

32" Class LED TV in Garage
Protective Diamond Plate on Garage Sidewalls
2,500 lb Rated Flush-Mount Tie-Downs
Ram-Air Garage Vents on Both Sides
Tuff-Ply Gas and Oil Resistant Garage Flooring
FastRamp™ Rear Ramp Door
Triple Insulated Garage Floor

Weather-Tek Package

R-Value Equivalent (R-40 Roof / R-45 Floor / R-11 Sidewalls / R-40 Garage Floor / R-24 Slide room Floor)
Fully Enclosed and Heated, Underbelly and Storage Area
Enclosed and Heated Low Point Drains
Engineered Underbelly Airflow Heat Paths
Stealth AC System w/ Insulated A/C Ducts
Attic Vent
Plumbing Line Insulation Barrier

See us for a complete list of features and available options!

All standard features and specifications are subject to change.

All warranty info is typically reserved for new units and is subject to specific terms and conditions. See us for more details.

Due to the current environment, our features and options are subject to change due to material availability.

Favorite RVs

Save your favorite RVs as you browse. Begin with this one!

We are here to help, call us at
520-482-3568 or Contact Us

We are here to help!

520-482-3568
Contact Us
Unlock Best Price!

*All calculated monthly payments are an estimate for qualified buyers only and do not constitute a commitment that financing or a specific interest rate or term is available. Financing terms may not be available in all Campers Inn locations. Campers Inn RV Sales is not responsible for any misprints, typos, or errors found in our website pages. Any price listed excludes sales tax, registration tags, and delivery fees. Manufacturer pictures, specifications, and features may be used in place of actual inventory in stock on our lot. Please contact us for availability as our inventory changes rapidly.
Manufacturer and/or stock photographs may be used and may not be representative of the particular unit being viewed. Where an image has a stock image indicator, please confirm specific unit details with your dealer representative.

Manufacturer and/or stock photographs may be used and may not be representative of the particular unit being viewed. Where an image has a stock image indicator, please confirm specific unit details with your dealer representative.

New 2026 Grand Design Momentum 399M

399M Floorplan

Specifications

Description

"This is the manufacturer's minimum allowed advertised price, contact us today for your unbeatable personalized quote."

Features

Why Do We Ask You For This Information?

Connect With Fellow RVers