01 What makes it unique
The 3623EB is the gear-hauler of the rear-living Montanas. Behind the lounge it adds a rear bike garage — a pass-through storage bay for bicycles and outdoor equipment — set into a four-slide floorplan with a kitchen island, a private front bedroom with a king bed and a 32-inch TV, and a rear room running a hide-a-bed sofa and powered theater seating across a 50-inch Smart TV and a 5,000-BTU fireplace. An outside shower, central vacuum and washer/dryer prep round it out.
RVUSA lists a 2,735-pound dry pin and a 2,590-pound payload; the 14,135-pound dry weight derives a GVWR near 16,725 pounds. A single 15,000-BTU Coleman Mach heat-pump air conditioner is standard with a triple-15K CX3 package optional, alongside a 35,000-BTU furnace, a 16-gallon water heater and an 18-cubic-foot residential refrigerator on a 2,000-watt inverter. The Legacy Edition option loads it toward four-season, off-grid use with Dexter disc brakes, a Furrion observation system, an electric power-cord reel, a surge protector, electric dump valves and a roof-mounted Starlink kit.
At an MSRP of $129,878 it is priced with the larger plans but aimed at a specific buyer — the couple who wants the bikes and the kayak paddles inside the coach, not strapped to the truck.
02 Full specifications
Dimensions
- Exterior length
- 40' 2"
- Exterior width
- 8' 0"
- Exterior height
- 13' 4"
- Interior height
- 7' 0"
Weights
- Dry / unit base weight
- 14,135 lbs
- GVWR (max loaded)
- 16,725 lbs
- Net cargo / payload
- 2,590 lbs
- Dry pin weight
- 2,735 lbs
Capacities
- Fresh water
- 70 gal
- Grey water
- 88 gal
- Black water
- 49 gal
- Refrigerator
- 18 cu ft
Construction
- Frame
- 12" I-beam · z-frame
- Walls
- 2" laminated fiberglass · lauan
- Roof
- Alpha TPO · walkable, 5" rafters
- Underbelly
- Four-Season · heated, 0° tested
Running gear
- Axles
- 2 (tandem)
- Hitch
- Fifth-wheel (in-bed)
- Suspension
- MORryde® CRE3000 · wet bolts
- Cooling
- Coleman Mach 15K · 50A
Galley & bath
- Cooktop
- 3-burner recessed
- Refrigerator
- 18 cu ft
- A/C
- 15K Coleman Mach heat-pump (CX3 triple-15K opt)
- Water heater
- Quick-recovery · gas/electric
Sleeping & layout
- Sleeps
- 4
- Slides
- 4
- Hitch type
- Fifth-wheel (in-bed)
- Primary bed
- King
03 The Montana floorplan family
Montana is Keystone's flagship luxury fifth wheel and the best-selling luxury fifth wheel in North America. The line runs to fifteen floorplans for 2026; the six highest-demand layouts are profiled here in full, and the rest — along with the lighter, lower-profile Montana High Country sub-line — are catalogued on the line hub. The 3623EB on this page is highlighted; each other profiled plan links to its own page.
| Floorplan | Nominal | Sleeps | Notable |
|---|---|---|---|
| 3123RL | 35 ft | 4 | Rear-living entry, kitchen island |
| 3100RL | 36 ft | 4 | New-2026 widebody, rear-living couples |
| 3231CK | 37 ft | 4 | Rear living, kitchen island + dual pantries |
| 3531RE | 39 ft | 4 | Rear entertainment, glass-door pantry |
| 3532SP | 39 ft | 4 | Side patio, king bed, theater seating |
| 3795FK | 40 ft | 6 | Front raised kitchen, rear full bath, sleeps 6 |
| 3623EB | 40 ft | 4 | Rear living, bike garage, four slides |
| 3761FL | 41 ft | 6 | Front living, bath-and-a-half, 5 slides |
| 3781RL | 41 ft | 4 | Best-selling rear living, kitchen island |
| 3857BR | 41 ft | 8 | Middle bunkroom + loft, family |
| 3901RK | 42 ft | 4 | Rear kitchen, bath-and-a-half, front master |
| 3915TB | 43 ft | 6 | Two full baths, bunkroom + loft |
| 3941FO | 43 ft | 6 | Front office full-timer, outside kitchen |
Montana is the best-selling luxury fifth wheel in North America and Keystone's flagship towable. The full line runs to fifteen floorplans for 2026, plus the lighter, lower-profile Montana High Country sub-line catalogued separately on the hub. Body specifications (lengths, heights, payload, tanks, refrigerator, sleeping, slides and A/C) are RVUSA-verified against the 2026 structured spec records, each page fp-slug and title checked; pin (hitch) weights are from the same records. Montana publishes a 18,000-pound GVWR across the luxury line; the lighter three-slide 3123RL entry carries a derived 16,580-pound GVWR, and the new widebody 3100RL has its dry weight and GVWR flagged as derived. Real loaded pin weights run higher — always weigh the loaded coach and confirm against your truck's payload and rear-axle ratings.
04 What owners & reviewers report
Rear bike garage
A pass-through gear bay behind the lounge for bicycles and outdoor equipment — the storage feature that defines this plan.
Four slides, rear living
A kitchen island and rear lounge in a four-slide layout — more open floor than the three-slide couples’ plans.
Legacy Edition for off-grid
Optional package adds disc brakes, observation camera, cord reel, surge protector, electric dump and roof Starlink — a meaningful four-season, off-grid upgrade.
GVWR derived
GVWR shown is the published dry weight plus the published payload; weigh the loaded coach and confirm the door sticker before matching it to a truck.
05 How it compares
A three-slide rear-living couples’ plan — lighter and cheaper without the bike garage or fourth slide.
The best-selling four-slide rear-living plan — a longer coach with a kitchen island and a conventional rear lounge.
Grand Design’s mid fifth wheel — a lighter alternative for couples without the in-coach gear bay.