# Forest River Sierra 3990FL

> Loft

3990FL is a fifth wheel floor plan by Sierra (Forest River).

## Specs (2026 model year)

| Spec | Value |
| --- | --- |
| Length | 43 ft 6 in |
| Sleeps | 10 |
| Slide-outs | 5 |
| Dry weight | 12,439 lbs |
| GVWR | 15,375 lbs |

## Model years

2026, 2025, 2024. Year-specific specs: `https://rvenvy.com/fifth-wheel-trailers/forest-river/sierra/3990fl?year={year}`

## Floor plan tags

loft, front living, rear bedroom

## Inventory

20 units currently for sale priced $68,950 to $99,995: https://rvenvy.com/fifth-wheel-trailers/forest-river/sierra/3990fl/inventory

Floor plan diagram: https://images.rvenvy.com/68164d51d5114e07249e66e703df73bfa12cbcb8022bb4e50c59de46469470a5/1024.webp

Canonical page: https://rvenvy.com/fifth-wheel-trailers/forest-river/sierra/3990fl