| Year | 2026 |
| Manufacturer | FOREST RIVER |
| Brand | SIERRA |
| Model | 3990FL |
| Type | Fifth Wheel |
| Class | |
| Fuel Type | |
| Status | New |
| Stock # | 26FR008 |
| Financing Available | |
| Warranty Available | |
| Odometer | |
| VIN | |
| Chassis | |
| Engine | |
| Transmission | |
| Suspension | N/A |
| Leveling | N/A |
| Exterior Length | 43.6 ft. |
| Dry Weight | 13439 lbs. |
| Sleeping Capacity | N/A person(s) |
| Interior Colour | N/A |
| Exterior Colour | N/A |
| Slideouts | N/A |
Disclaimer: Product information, pricing and photos are as accurate as possible and are subject to change without notice.







The 2026 Forest River Sierra 3990FL is a luxury front-living (FL) fifth wheel that masterfully hides a massive amount of sleeping space within a sophisticated, residential-style layout. It is best known for its "hidden" loft and five-slide-out configuration.
Core SpecificationsExteri...