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New 2026 Jayco Seismic 399

Toy Hauler Fifth Wheel

Stock #JS3990149

McDonough, GA

"Get ready to experience next-level luxury and power — the all-new 2026 Jayco Seismic 399 is on its way, and with Jayco’s legendary build quality and cutting-edge features, this toy hauler is redefining adventure before it even hits our lot.

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Sale Price: $108,995
MSRP: $141,197
Save: $32,202

Payments From: $869 /mo.

46ft long
14,950 lbs
Sleeps 9

3 slides
Bath and a Half

Two Entry/Exit Doors

See All Specs

Specifications

Sleeps	9	Slides	3
Length	45 ft 11 in	Ext Width	8 ft 6 in
Ext Height	13 ft 2 in	Int Height	8 ft 3 in
Exterior Color	Titanium, Metallic Red, Charcoal, Metallic Copper, Metallic Blue Full Body Paint Choices	Hitch Weight	3370 lbs
GVWR	20400 lbs	Dry Weight	14950 lbs
Cargo Capacity	5450 lbs	Fresh Water Capacity	106 gals
Grey Water Capacity	87 gals	Black Water Capacity	87 gals
Tire Size	17.5"	Furnace BTU	35000 btu
Generator	Yamaha 6000 Watt	Fuel Capacity	30 gals
Number Of Bunks	1	Available Beds	Queen
Refrigerator Type	12 Volt	Refrigerator Size	17 cu ft
Cooktop Burners	3	Number of Awnings	3
Garage Size	13 ft 6 in	LP Tank Capacity	30 lbs
Water Heater Capacity	16 gal	Water Heater Type	Gas/Electric DSI
AC BTU	30000 btu	TV Info	LR 4K Smart LED HDTV
Awning Info	21' Electric w/LED Lights, 11' Electric, 10' Rear	Axle Count	3
Washer/Dryer Available	Yes	Number of LP Tanks	2
Shower Type	Walk-In Shower	Electrical Service	50 amp
VIN	1UJCGSCVXT18M0149

Description

Jayco Seismic toy hauler 399 highlights:

Party Deck
Queen Bed with Convertible Sofas
Overhead Garage Loft with Storage
Walk-in Shower
60" x 80" Queen Bed
4K Smart LED HDTV

Get ready for outdoor adventures in this spacious toy hauler. Your guests will have the 13' 6" garage with queen bed with convertible sofa and a loft for added sleeping space, plus there is overhead storage for your things and a side man door to come and go easily. The main living area includes dual opposing slides with an L-shaped tri-fold sofa along the roadside and your dinette and refrigerator plus pantry in the curbside slide. Head up the steps to your front private bedroom with the dual entry bath accessible from the hall and inside the master bedroom. Here you will all enjoy a walk-in shower, toilet, and vanity with a sink, plus overhead storage. The bedroom features a third slide out housing a queen bed for added floor space, plus a full front walk-in closet, a dresser, and washer/dryer prep!

One look at the Seismic toy haulers by Jayco, and you'll never go back! Each model features a custom automotive-grade vinyl exterior graphics package, a painted fiberglass front cap with built-in LED lighting, and 102" wide-body structural steel I-beam construction. You'll find the pass-through storage with Slam-Latch baggage doors will make unpacking easier than ever, and the rear ramp door/patio with anti-slip, non-skid flooring will allow you to unload your toys with no trouble at all. These toy haulers feature a three seasons garage wall/doors, a 30 gallon fuel tank with a timer, and exterior marine-grade speakers to keep the party going. The Climate Shield zero degree tested weather protection includes a 35,000 BTU furnace, PEX plumbing, and a fully enclosed and heated underbelly so you can enjoy your adventures year around. And we haven't even touched on the interior luxuries you'll find, like solid hardwood cabinet doors, residential vinyl flooring made in the USA, night shades, and more!

With over 45 years as a family run business we carry great new products from brands like Jayco, Forest River, Venture RV and DRV, and Crossroads and Thor Motor Coach. Southern RV also features certified pre-owned RV's from companies like Keystone, Brinkley, Heartland, Airstream and Alliance,Tiffin and Winnebago. Come into our Cumming or Mcdonough locations and take advantage of the exceptional customer experience and marvelous pricing that has positioned Southern RV as one of the most awarded RV Dealers in the America with two RV Business Top 50 Dealer awards, three Inc. 5000 awards, as well as a Top Ten Venture RV Dealer for four years in a row.

*Advertised sale price may be inclusive of a Finance Concession, please consult a Southern RV sales associate for details.

Features

Standard Features (2026)

PLEASE NOTE: Features and options separated by type below

------------------------------------------------------------

FIFTH WHEELS

Exterior Equipment

102 in. wide-body structural steel I-beam construction
Stronghold VBL™ aluminum-framed and vacuum-bond laminated gel-coated fiberglass exterior walls and slide room end walls
Magnum Truss™ XL6™ Roof System (strongest tested roof in the industry) with Alpha roof membrane system (limited lifetime warranty)
Painted fiberglass front cap with clear coat and built-in specialty LED lighting
Custom automotive-grade vinyl exterior graphics package
Climate Shield™ zero-degree tested weather protection includes:
- 35K BTU output furnace
- Double-layer fiberglass batt insulation in ceiling and floor
- Double-sided radiant barrier insulation (roof and floor)
- Fully enclosed and heated underbelly (ducted)
NPS – Powered by Yamaha® 6,000-watt generator with built-in pure sine inverter (gas/C.A.R.B. certified)
6-point hydraulic auto-leveling system
Battery disconnect switch
Detachable shore power cord
Dual 30 lb. propane bottles with auto regulator
Water heater bypass
LP quick-connect
Exterior marine-grade speakers
Digital TV antenna
Folding roof ladder
LED exterior lighting package
JaySMART™ (Safety Markers and Reverse Travel) LED lighting (patented)
HELIX Cooling System™ (industry exclusive) includes:
- Three exterior-mounted 13,500 BTU soft-start, high-efficiency, ducted A/Cs (living room and bedroom)
- Directional and closeable A/C vents
- Insulated dual-duct design
Pass-through storage with Slam-latch™ baggage doors
Under-mounted spare tire
Fully enclosed, LED-lighted universal docking center with:
- Black tank flush
- Winterization and sanitation hookups
- Quick-connect outside shower
- Satellite prep

Interior Equipment

Olympic king bed (359 & 413)
Residential quilted bedspread
Gas-strutted under-bed storage
Washer/dryer prep
12V charging station
Bathroom skylight
Central command center with built-in tank monitoring
Custom interior design (Dune Gray)
LED interior lighting throughout
LED fireplace with electric space heater (select models)
No in-floor heat registers throughout the coach
Vinyl flooring in slideouts (no carpet)
Residential vinyl flooring (made in the USA)
Hardwood safety handrail on hallway steps
Carbon monoxide and LP detector
5/8 in. tongue-and-groove joined plywood main floor decking and 3/8 in. tongue-and-groove plywood roof decking
Handcrafted and glazed doors, drawers, and trim
Solid hardwood cabinet doors
Residential finished dovetail-jointed drawers throughout
Heavy-duty, 75 lb., full-extension, steel ball-bearing drawer guides
SuperSofa™ or theater seats with heat, massage, and LED lighting (select models)
Stain-protected fabric on all furniture
Residential “Do it all” sink with pull-out kitchen faucet, glass rinse, and vegetable rinse
Porcelain foot-flush toilet
Inverter pre-wire

Customer Value Package (Mandatory)

On-demand tankless hot water heater
50-amp service
Overlander II Solar Package: 30-amp solar controller with (2) roof-mounted 200W solar panels and a 1,800W inverter
17 cu. ft. 12V refrigerator
30 in. space-saver microwave
Residential 21 in. oven with three burners
4K Smart LED HDTV with fully digital HDMI® output
Touch-screen Bluetooth® stereo with four speakers
Electric patio awning with integrated RGB LED lights (multi-color with remote control)
MORryde® strut-assisted fold-away entrance steps (main entrance)
Custom black, machined aluminum rims
Keyed-Alike™ lock system
Bathroom power vent
Night roller shades
Hidden hinges and magnet door catches on cabinet doors

5 Star Handling Package (Mandatory)

17.5 in., 16-ply “H” rated Cooper® tires
Dexter® axles with ABS and Tow Assist – includes Nev-R-Adjust® brakes and E-Z Lube® hubs
MORryde® CRE-3000™ Suspension System
Rota-Flex® king pin
Wet bolt fasteners, bronze bushings, and 4K lb. leaf springs
2nd electric patio awning with integrated RGB LED lights (multi-color with remote control)

Ramp and Cargo Equipment

30 gal. fuel tank with timer
Garage D-rings mounted to steel frame
HappiJac® electric-lift queen beds/convertible sofas with folding armrests and cup holders
Three-season removable garage wall/doors
Tuff-ply™ rubberized garage floor liner
Rear ramp door and patio with anti-slip, non-skid flooring
Ramp patio kit with exterior steps
Rear electric patio awning
LED high-intensity ramp lights
Ram air vents and power roof vent

Options

Frameless, dual-pane, tinted safety-glass windows
Outside HALO™ griddle for outside kitchens or JayPort® system (includes LP quick-connect) (select models)
Queen residential foam-top mattress (395 & 399)
Retractable half-bath wall in garage (395 & 399)

---------------------------------------------------------------

TRAVEL TRAILERS

Exterior Equipment

102 in. wide-body structural steel I-beam construction
Magnum Truss™ XL6™ Roof System (strongest tested roof in the industry)
Stronghold VBL™ aluminum-framed and vacuum-bonded, laminated gel coated, fiberglass exterior walls and slideroom end walls
Painted fiberglass front cap with clear coat and built-in specialty LED lighting
Climate Shield™ zero-degree tested weather protection:
35K BTU output furnace
Double layer fiberglass batt insulation in ceiling and floor
Double sided radiant barrier insulation (roof and floor)
Fully enclosed and heated underbelly (ducted)
Custom automotive-grade vinyl exterior graphics package
Lippert Solid Step®
Backup camera prep
Power tongue jack
50-amp service
Detachable shore power cord
Digital TV antenna
Satellite prep
Black tank flush, winterization and sanitation
Quick-connect outside shower
Water heater bypass
LP quick-connect
HELIX Cooling System™ (industry exclusive):
Jayco exclusive insulated dual duct design
Directional and closeable A/C vents
Slam-latch™ baggage doors
LED exterior lighting package

Interior Equipment

5/8 in. tongue-and-groove joined plywood main floor decking and 3/8 in. tongue-and-groove plywood in the roof
PEX plumbing
Carbon monoxide and LP detector
Central command center with built-in tank monitoring
Inverter pre-wire
LED fireplace with electric space heater (select models)
LED interior lighting throughout
Custom interior design
Solid hardwood cabinet doors
Handcrafted and glazed doors, drawers and trim
Residential finished dovetail-jointed drawers throughout
Heavy-duty, 75 lb., full-extension, steel ball-bearing drawer guides
No in-floor heat registers throughout the coach
Bathroom skylight
Porcelain foot flush toilet
Medicine cabinet with custom framed mirror
High Rise Kitchen Faucet
King bed
Residential quilted bedspread
Stain protected fabric on all furniture
Vinyl flooring in slide outs (no carpet)
Residential vinyl flooring (made in the USA)
Roll down garage screen (*unless 3 season door is selected)

Customer Value Package (Mandatory)

60K BTU On-demand tankless hot water heater
12V refrigerator
Space-saver microwave
13.5K BTU A/C
17 in. oven with 3 burners
4K Smart LED HDTV
Bluetooth® stereo with 4 speakers
Roller-shades
Soft close hidden hinges and magnet door catches on cabinet doors
Drop-down knife rack
Integrated cup washer at sink
Bathroom power vent
Roll-away shower door
Electric awning
Roof ladder prep
JayPort® 2 in. mount (for outside accessories)
Keyed-Alike™ lock system
(2) 20 lb. LP gas bottles with auto-regulator, ABS cover, & fill gauge
106 gal. fresh water capacity
Overlander 1 Solar Package: 200W panel and 30-amp solar controller)

Ramp And Cargo Equipment (Mandatory)

30 gal. fuel tank with locking, enclosed pump and timer
5,000 lbs. Garage D-rings mounted to the steel frame
HappiJac® electric-lift queen beds with convertible sofas
LED high-intensity ramp lights
Ram air vents and power roof vent
Tuff-ply, rubberized garage floor liner
Weather resistant rear ramp door and patio with anti-slip, non-skid flooring

5 Star Handling Package (Mandatory)

Dexter® axles with Nev-R-Adjust® brakes and E-Z Lube® hubs
Wet bolt fasteners, bronze bushings, and 4,000 lb. leaf springs
CRE-3000 suspension
16 in. aluminum rims
Under-mounted spare tire

Options

6,000W NPS inverter generator with remote start
Second A/C
3-season removable garage wall
Rear patio awning
Slideout awning
Overlander 2 Solar Package: (2) 200W panels, MPPT 30-amp solar controller and 1800W inverter
Queen bed in place of king

Please 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.

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Displayed prices include all available discounts and rebates. All customers may not qualify: please ask an associate for details.

Southern RV 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 units on our lot. Please contact us @770-477-0552 for availability as our inventory changes rapidly. All calculated payments are an estimate only and do not constitute a commitment that financing or a specific interest rate or term is available.

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 Jayco Seismic 399

399 Floorplan

Specifications

Description

Features