01 What makes it unique
The 40DB is the roster’s answer to the question fifth wheels rarely answer well: where does the second household sleep? Two real bedrooms — the master forward, a second bedroom aft — each pair with a full bathroom, and two entry doors keep the households independent. The factory rates it for up to eight, tying the 37MD for the line’s top count, and it is the tallest coach in the roster at 13 feet 1.
The utilities are sized to the mission: a 100-gallon black tank (double the line norm) against 50 grey — the inverted split two bathrooms demand — and 120 pounds of LP, the largest reserve in the line, feeding the 40,000-BTU ThermaShield furnace. The platform is the full Bighorn build — 12-inch I-beam drop frame, 102-inch wide-body, CoreShield walls, painted cap, frameless windows, TrussXL truss, dual 15,000-BTU Whisper Quiet air, tankless water heater, hydraulic auto-level, mandatory Premium Package — with one deletion: the 3,000-pound rear tow hitch standard elsewhere is not available on this floorplan. The printed 18,850-pound GVWR — the highest in the line — equals 16,110 dry plus 2,740 cargo exactly on tandem 8,000-pound axles.
At 16,110 pounds dry with a 2,925-pound pin, this is committed one-ton-dually territory loaded. Eight people against 2,740 pounds of margin is workable only with discipline — and the 50-gallon grey tank, not the 100-gallon black, will set the dump-station rhythm. For two couples splitting a coach or a family living aboard with kids old enough to want a door, nothing else in the line is drawn this way.
02 Full specifications
Dimensions
- Exterior length
- 43' 10"
- Exterior width
- 8' 6"
- Exterior height
- 13' 1"
- Interior height
- 8' 7"
Weights
- Dry / unit base weight
- 16,110 lbs
- GVWR (max loaded)
- 18,850 lbs
- Net cargo / payload (CCC)
- 2,740 lbs
- Dry pin weight
- 2,925 lbs
Capacities
- Fresh water
- 75 gal
- Grey water
- 50 gal
- Black water
- 100 gal
- Refrigerator
- GE 21 cu ft residential
Construction
- Frame
- 12″ steel I-beam · drop frame
- Sidewalls
- CoreShield 2″ laminate · high-gloss gel coat
- Front cap
- Painted fiberglass · clearcoat · LED
- Roof
- TrussXL truss · Alpha membrane (limited lifetime)
Running gear
- Axles (factory)
- 2 x 8000
- Hitch
- Fifth wheel · dry pin 2,925 lb
- Tires
- 215/75R17.5'H'
- LP
- 120 lb total
Galley & systems
- Refrigerator
- GE 21 cu ft residential · 1,800W inverter
- A/C
- 2 × 15,000 BTU Whisper Quiet
- Water heater
- Tankless
- Furnace
- 40,000 BTU
Sleeping & layout
- Sleeps
- Up to 8 (factory)
- Primary bed
- Two bedrooms
- Layout
- Double-bedroom, two-full-bath quad-slide — front master, second rear bedroom, two full bathrooms, two entry doors, 16-foot + 10-foot awnings
- Awnings & entries
- 2 · 16′ + 10′ · 2 entries (RVUSA)
03 Bighorn floorplan family
Heartland's Bighorn line — the flagship luxury fifth wheel of the relaunched range: seven 2026 floorplans, every one a 102-inch wide-body on a 12-inch steel I-beam drop frame with a painted fiberglass front cap, CoreShield laminated sidewalls in high-gloss gel coat, the ThermaShield zero-degree package with a 40,000-BTU furnace, two 15,000-BTU Whisper Quiet air conditioners, and a mandatory Premium Package that includes six-point hydraulic auto-leveling, a GE 21-cubic-foot residential refrigerator with an 1,800-watt inverter and a GE appliance suite. All seven plans are profiled in depth on the Bighorn hub with verified weights.
| Floorplan | Nominal | Sleeps | Notable |
|---|---|---|---|
| 31RL | 36 ft | 4 | Rear-living entry — shortest, lightest, friendliest pin |
| 36RK | 40 ft | 4 | Rear-kitchen plan — the galley takes the back wall |
| 38RE | 43 ft | 4 | Rear-entertainment quad-slide — most-listed; 137-gal grey |
| 37MD | 43 ft | 8 | Middle-den quad-slide — two living zones |
| 39RK | 43 ft | 4 | Rear U-kitchen, bath-and-a-half — respec’d stretch; best margin |
| 39FL | 44 ft | 4 | Front-living flagship — five slides, heaviest pin |
| 40DB | 44 ft | 8 | Two bedrooms, two full baths — the multi-family flagship |
Every Bighorn is a 102-inch wide-body on the 12-inch I-beam drop frame, and the Premium Package is mandatory — its content (hydraulic auto-level, the GE residential appliance suite with inverter, central vacuum, gel-coat sidewalls) is part of the Base MSRP shown. This is a published-GVWR-clean line: dry plus cargo equals the printed GVWR exactly on all seven plans. RVUSA and the library brochure carry an early-print weight set superseded on five plans — the current factory pages and the June-2026 dealer-network brochure agree exactly and are used throughout (the 39RK was respecified from a 40-foot-4 two-slide draft to the current 43-foot-3 three-slide build, logged). Dealer placards typically run above Base MSRP while negotiated street pricing runs below it. A fifth wheel loads its pin into the truck bed — confirm the pin weight against the tow vehicle's payload placard, not its tow rating.
04 What owners & reviewers report
Two of everything
Two bedrooms, two full baths, two entries — the multi-household architecture, unique in the roster.
The inverted tank split
100 black / 50 grey — sized for two toilets, but the grey side will fill first under daily showers. Plan dumps around grey.
No rear tow hitch
The 3,000-pound four-way-pin tow hitch standard on every other 2026 Bighorn is not available on the 40DB — toad and trailer plans should note it.
120 pounds of propane
The biggest LP reserve in the line — matched to winter living with the 40,000-BTU furnace.
05 How it compares
The other eight-sleeper — a middle den instead of the second bedroom-and-bath pair, 460 pounds lighter.
The entry — for buyers who need the Bighorn build without the second household.
The multi-bath luxury field — the 40DB counter is the true second bedroom and the 100-gallon black tank.