01 What makes it unique
The 3904BH is the top of the Influence bunkhouse range: a private bunkhouse sleeping five, an outdoor kitchen (griddle, sink and beverage cooler), a U-shaped dinette, dual entry doors (one into a half bath for a bath-and-a-half) and quad slides in a widebody layout, with theater seating and a front private bedroom — the whole coach sleeping nine, the most in the line. Dual opposing living slides open a wide main level. The equipment is the standard Influence package — a 16-cubic-foot 12-volt refrigerator, gel-coat sidewalls and the 330-watt Influence Solar Package — on the 101-inch wide-body platform inside a five-sided welded-aluminum cage, under a walk-on Thermal Roof, with a fully enclosed, heated underbelly.
Grand Design publishes a 19,000-pound GVWR against the 16,000-pound dry weight — the heaviest in the line — leaving a 3,000-pound cargo capacity and a 2,700-pound dry pin. A 30,000-BTU air-conditioning rating and 83/106/106-gallon fresh/grey/black tanks are standard, with six-point auto-leveling available. RVUSA does not carry a starting MSRP for the 3904BH. It is the Influence for large families who want a private bunkhouse, an outdoor kitchen and a bath-and-a-half in the longest coach in the line, towed with a one-ton truck.
02 Full specifications
Dimensions
- Exterior length
- 42' 8"
- Exterior width
- 8' 5" (101″ wide-body)
- Exterior height
- 12' 9"
- Chassis
- 101″ wide-body · welded-aluminum five-sided cage
Weights
- Dry / unit base weight (UVW)
- 16,000 lbs
- GVWR (max loaded)
- 19,000 lbs
- Net cargo / payload (CCC)
- 3,000 lbs
- Dry pin (hitch) weight
- 2,700 lbs
Capacities
- Fresh water
- 83 gal
- Grey water
- 106 gal
- Black water
- 106 gal
- Refrigerator
- 16 cu ft 12V
Construction
- Body cage
- Five-sided welded-aluminum cage
- Roof
- Walk-on · Thermal Roof R-40 (fiberglass + radiant foil, vented attic)
- Walls
- Fully laminated R-11 · welded-aluminum framed, rigid foam
- Main floor
- Triple-insulated R-45 (radiant foil + fiberglass)
- Underbelly
- Fully enclosed & heated (all-weather) · heated tanks
- Exterior
- Gel-coat sidewalls
Running gear
- Axles
- 2 (tandem)
- Hitch
- Fifth-wheel (in-bed) pin box
- Solar
- Influence Solar Package · 330W panel, controller, inverter prep
- Leveling
- 6-point hydraulic auto-leveling (optional)
Galley & systems
- Refrigerator
- 16 cu ft 12-volt residential
- Air conditioning
- 30,000 BTU
- Solar / electrical
- Influence Solar Package · 330W · inverter prep
- Water heater
- Gas / electric
Sleeping & layout
- Sleeps
- 9
- Slides
- 4
- Entries
- 2
- Awnings
- 2
- Primary bed
- Queen (king optional)
Drawn to scale
Weight budget
Size, with end view
Holding tanks
Axles, wheels and nose shape are schematic; not a floorplan. Data: dataset.
Towing it
Loaded range: 15–25% of GVWR on the pin, a rule of thumb, not a measurement of this unit. No truck ratings or hitch classes (why; NHTSA, DOT HS 809 433).
03 The Influence floorplan family
Influence is Grand Design's residential-style full-profile fifth wheel on the 101-inch wide-body platform that underpins the flagship Solitude, offered at a lower entry point — a cross-shop against Keystone's Cougar and Montana, Jayco's Eagle and North Point, with the Grand Design Reflection a step below. The 2026 line runs to seven floorplans, all profiled in full and linked below. The 3904BH on this page is highlighted.
| Floorplan | Nominal | Sleeps | Notable |
|---|---|---|---|
| 2903RL | 34 ft | 4 | Rear living, kitchen island, front master |
| 3003RL | 34 ft | 4 | Rear living, kitchen island, big payload |
| 3203GK | 35 ft | 3 | Rear galley kitchen, private front bedroom |
| 3503GK | 38 ft | 4 | Rear galley kitchen, stretched living space |
| 3704BH | 40 ft | 8 | Private bunk room, quad slides, family |
| 3804DS | 42 ft | 6 | Two masters, two full baths, loft |
| 3904BH | 42 ft | 9 | Bunkhouse, outdoor kitchen, bath-and-a-half |
Influence is Grand Design's residential-style full-profile fifth wheel — the 101-inch wide-body platform that underpins the flagship Solitude, offered at a lower entry point. The 2026 line runs to seven floorplans, all profiled here in full. Every Influence rides the 101-inch wide-body platform inside a five-sided welded-aluminum cage, under a walk-on Thermal Roof (R-40, fiberglass and radiant foil over a vented attic), with fully laminated R-11 walls, a triple-insulated R-45 main floor and a fully enclosed, heated all-weather underbelly with heated tanks. The Influence Solar Package — a 330-watt panel with controller and inverter prep — a 16-cubic-foot 12-volt refrigerator and gel-coat sidewalls are standard, with six-point hydraulic auto-leveling and a third air conditioner with heat pump available. Dry weight, GVWR, CCC and pin are published per plan and each plan's dry weight plus CCC equals its GVWR exactly. Real loaded pin weights run higher — always weigh the loaded coach and confirm against your truck's payload and rear-axle ratings.
04 Notes on this floorplan
Bunkhouse + outdoor kitchen + bath-and-a-half
A private bunkhouse, an outside kitchen and a second half bath behind dual entry doors — the most family-capable Influence, sleeping nine.
Longest, heaviest Influence
At about 42½ feet and a 16,000-pound dry weight it is the biggest coach in the range.
Wants a one-ton truck
A 19,000-pound-GVWR widebody fifth wheel with dual entries — confirm a properly rated one-ton truck’s payload and rear-axle rating.
05 How it compares
Jayco’s North Point — a comparable large family full-profile fifth wheel with an outdoor kitchen.
The 3704BH bunkhouse — shorter and lighter, without the outdoor kitchen or half bath.
The flagship Solitude on the same platform — the top of the Grand Design full-profile range.
06 Loading it for a trip
A full 83-gallon fresh tank is about 692 lb of water (water counts as cargo: 49 CFR 571.120 S10.4.2), 23% of the 3904BH’s 3,000 lb cargo capacity, leaving 2,308 lb (256 lb per rated berth). Across 7 Influence floorplans the water share runs 13% to 34%, and 1 gives up more than this one. Nearest on that share: Influence 3503GK at 23% and Influence 3704BH at 34%. Your own unit’s figure is on the label inside its entry door (49 CFR 571.120 S10.4.3).
07 Where this floorplan sits
Closest sibling: the Influence 3704BH, nearest on the published figures. It differs on 7 of the 9 fields both publish (this plan first): length 42 ft 8 in vs 40 ft 4 in; sleeps 9 vs 8; dry weight 16,000 lb vs 14,798 lb; GVWR 19,000 lb vs 16,800 lb; cargo capacity 3,000 lb vs 2,002 lb; dry hitch weight 2,700 lb vs 2,728 lb; fresh tank 83 gal vs 81 gal. They match on grey tank and black tank.
| Influence plans | This plan | Position, low to high | Range |
|---|---|---|---|
| GVWR (lb) | 19,000 | 6–7 of 7 | 15,000–19,000 |
| Dry weight (lb) | 16,000 | 7 of 7 | 11,800–16,000 |
| Cargo capacity (lb) | 3,000 | 3 of 7 | 2,002–5,500 |
| Dry hitch weight (lb) | 2,700 | 5 of 7 | 2,190–2,911 |
| Length | 42 ft 8 in | 7 of 7 | 34 ft 5 in–42 ft 8 in |
| Fresh tank (gal) | 83 | 5–7 of 7 | 81–83 |
| Black tank (gal) | 106 | 5–7 of 7 | 53–106 |
| Sleeps | 9 | 7 of 7 | 3–9 |
Either side of it by GVWR: Influence 3804DS matches it at 19,000 lb GVWR.
| Nearest Influence siblings | Length | Sleeps | Dry (lb) | GVWR (lb) | CCC (lb) | Hitch (lb) | Fresh (gal) |
|---|---|---|---|---|---|---|---|
| Influence 3904BH | 42 ft 8 in | 9 | 16,000 | 19,000 | 3,000 | 2,700 | 83 |
| Influence 3704BH | 40 ft 4 in | 8 | 14,798 | 16,800 | 2,002 | 2,728 | 81 |
| Influence 3804DS | 42 ft 6 in | 6 | 14,603 | 19,000 | 4,397 | 2,911 | 83 |
| Influence 3503GK | 38 ft 3 in | 4 | 13,868 | 16,800 | 2,932 | 2,670 | 81 |
| Influence 2903RL | 34 ft 5 in | 4 | 11,800 | 15,000 | 3,200 | 2,190 | 81 |
| Influence 3203GK | 35 ft 11 in | 3 | 12,712 | 16,800 | 4,088 | 2,471 | 81 |
All 7 Influence floorplans: Influence line hub.
| Other lines, nearest by GVWR | GVWR (lb) | Dry (lb) | Sleeps | Length |
|---|---|---|---|---|
| 3904BH | 19,000 | 16,000 | 9 | 42 ft 8 in |
| Momentum 344M | 19,000 | 15,910 | 6 | 39 ft 11 in |
| Paradigm 385FL | 19,000 | 15,487 | 6 | 41 ft 4 in |
| Solitude 310GK | 19,000 | 12,100 | 4 | 34 ft 4 in |
| Seismic 3512 | 18,995 | 14,285 | 7 | 41 ft 7 in |
| Riverstone 39RKFB | 18,975 | 16,511 | 4 | 42 ft 1 in |
| Bighorn 40DB | 18,850 | 16,110 | 8 | 43 ft 10 in |
Against the 3904BH: the Momentum 344M is 3 ft shorter and sleeps 3 fewer; the Paradigm 385FL is 1 ft shorter and sleeps 3 fewer; the Solitude 310GK is 8 ft shorter and sleeps 5 fewer.
08 Common questions about the 3904BH
How much does the 3904BH weigh?
16,000 lb dry; 19,000 lb GVWR, the most it may weigh loaded.
How much can the 3904BH carry?
3,000 lb, 16% of its GVWR (median across 307 fifth wheels here: 19%). A full fresh tank uses 692 lb of it.
What is the pin weight of the 3904BH?
2,700 lb dry, 17% of the dry weight (median across 386 fifth wheels here: 19%).
What size tow vehicle does the 3904BH need?
A tow rating of at least 19,000 lb, plus payload for the loaded pin weight, passengers and cargo.
How many people does the 3904BH sleep?
It is rated to sleep 9. No other Influence floorplan here is rated for more.
What are the tank capacities on the 3904BH?
Fresh 83, grey 106, black 106 gallons. Off hookups, fresh water runs out first.
How long is the 3904BH?
42' 8" overall, tongue or pin box included.
From the figures above.
09 What this page publishes, and what it does not
16 of the 18 fields this catalogue tracks are published for the 3904BH. Not published: interior height, tire specification.
Sourcing rules: methodology.
10 Manuals & documents
Sources: granddesignrv.com (linked below); the full source note is at the foot of the page.
11 NHTSA safety record
No recall campaign or owner complaint in our NHTSA data names the Influence line. Read that as no result found, not as a clean record.
Recall coverage here is not complete, and complaints are owners’ unverified reports (how this record is built). Check a specific VIN at NHTSA before you buy. Full tables are on the Influence line page.