2026 Sierra 3990FL
About This Sierra 3990FL
Forest River Fifth Wheel · 43' · Sleeps 10 +
Wherever you go, the Sierra line up will ensure you make the most out of every adventure. Unique floorplan designs like bunkhouses, front living spaces, or mid-bunk/offices will accommodate any traveler or group. Automatic level up, 16.8 french door refrigerator, and underbelly armor combine to create a perfect balance of size, space, features and luxury.
Unit details
- Manufacturer
- Forest River
- Brand
- Sierra
- Model
- 3990FL
- Type
- Fifth Wheel
- Condition
- New
- Year
- 2026
- Interior Decor
- SwitchBack
- Stock No.
- 26G055083
- Order No.
- RVN31863
- VIN
- 4X4FSES25TJ055083
Specifications
Key measurements for this model, with the manufacturer's full spec sheet below.
Key measurements
- 43'Overall length
- 12,439 lbsDry weight
- 10 +Sleeps
- 5Slide-outs
| Specification | Imperial | Metric |
|---|---|---|
| Cargo Capacity | 2,936 lbs | 1,331.75 kg |
| Dry Weight | 12,439 lbs | 5,642.24 kg |
| GVWR | 15,375 lbs | 6,973.98 kg |
| Pin Weight | 2,825 lbs | 1,281.40 kg |
| Overall Height | 13' 4" | 4.06 m |
| Overall Length | 43' 6" | 13.26 m |
| Overall Width | 96" | 243.84 cm |
| Black Water Tank | 50 gal | 189.27 l |
| Fresh Water Tank | 50 gal | 189.27 l |
| Gray Water Tank | 80 gal | 302.83 l |
As published by the manufacturer for this model.
Equipment & Options
Factory equipment included on this unit as configured.
- Chef’s Kitchen Package
- 16 Cubic FT Stainless Refrigerator (12V)
- Stainless Range, Seal Burners with Cast Iron Grates
- Solid Wood Cabinet Door and Drawer Fronts (50 lb drawer guides)
- Solid Surface Countertops
- Commercial Style Kitchen Faucet
- 30” Over-the-Range Stainless Microwave
- Countertop Extension
- Designer Backsplash
- RVIA Seal
- Summit Package
- Electric Leveling System
- Goodyear Endurance Tires with 7,000lb axles
- 2” Rear Receiver Hitch and 4-Pin Connector (N/A 3990FL and 4002FB)
- Two 15,000BTU Air Conditioners with 3rd Air Conditioner Prep
- Anti-lock Braking System
- Tire Pressure Monitoring System
- 60,000BTU On Demand Water Heater
- 40,000BTU Furnace
- BoonDocker Solar System-200W Panel with controller & battery
- Solid Steps with Strut Assist (Wherever Available)
- Heated and Enclosed Holding Tanks (12V pads)
- Washer and Dryer Prep (Standard on 3800RK and 3900HBLR)
- Underbelly Armor
- Soft Close Residential Drawers & Cabinets Throughout
- 50” Smart Television / 65” Smart Television 3900HBLR only
- 4 Camera Security Prep with Back-Up Cam
- Power Fan in Bathrooms and Kitchen
- Enclosed, One-Piece Docking Station
- Color Matched Fiberglass Exterior
- Aerodynamic Two Tone Fiberglass Painted Front Cap with Lights
- High Efficiency Radiant Foil (Roof and Floor)
- Spare Tire
- LatchXtend Door Handle
- Ceiling Paddle Fan (where available)
- Portable Vacuum
Included with every new RV
Free- 12V Deep Cycle Battery
- Propane in Tanks
- Dealer Prep
- North American Service
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We Deliver Nationwide
Pick it up at our dealership, or we bring it to your driveway.
Dealership pickup: 5555 Kennel Rd, Trenton, OH 45067 (free).
Map of the United States showing Couch's RV Nation at 5555 Kennel Rd, Trenton, OH 45067. No destination entered yet.
- RV Nation · Trenton, OH
Route to
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- Dealership pickup in Trenton, OH
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