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2025 Forest River Sandpiper 3660MB
by Forest River
Full Specifications
General Info
| Manufacturer | Forest River |
| Country of Origin | USA |
| Year | 2025 |
| Category | Fifth Wheel |
| Subcategory | — |
Dimensions & Weight
| Length | 35.5 ft |
| Width | 8.5 ft |
| Height | 13.5 ft |
| Dry Weight | 8,600 lbs |
| GVWR | 11,500 lbs |
| Hitch Weight | 1,460 lbs |
| Cargo Capacity | 2,900 lbs |
Engine & Chassis
| Fuel Type | N/A |
| Engine | — |
| Chassis | — |
| Horsepower | — |
| Fuel Capacity | — |
Living & Off-Grid
| Sleeping Capacity | 4 |
| Slide-Outs | 1 |
| Awning Length | 20.5 ft |
| A/C | 13,500 BTU |
| Furnace | 16,000 BTU |
| Fridge | Single-door compressor |
| Fresh Water | 94 gal |
| Gray Water | 53 gal |
| Black Water | 38 gal |
| Solar | 300 W |
| Battery | 250 Ah |
| Inverter | 2,000 W |
About the 2025 Forest River Sandpiper 3660MB
For those who want the maximum amount of living space in a towable package, the 2025 Forest River Sandpiper 3660MB by Forest River delivers exactly that. This 2025 fifth wheel leverages its unique hitch design to create split-level luxury.
With an overall length of 35.5 feet, 8.5 feet wide and with a height of 13.5 feet, the 2025 Forest River Sandpiper 3660MB has a dry weight of 8,600 lbs, with a GVWR of 11,500 lbs, giving you roughly 2,900 lbs of payload room. Thanks to one slide-out, the interior transforms into a surprisingly roomy living space once deployed.
Sleeping up to 4 people, this model works well for small families or traveling duos who appreciate extra guest capacity. Convertible dinettes or sofa beds provide flexibility between day and night configurations without sacrificing comfort.
Boondocking enthusiasts will value the a generous 94-gallon fresh water supply, 53 gallons of gray water holding, a 38-gallon black water tank. Energy management is handled by 300-watt solar charging capability, 250 amp-hours of battery storage, a 2000-watt inverter for household AC power. 13,500 BTU of air conditioning handles warm-weather comfort, and 16,000 BTU of furnace output tackles chilly evenings. Food storage is handled by a Single-door compressor fridge. A 20.5-foot awning extends your living space outdoors, providing shade and shelter.
At 8,600 pounds dry, the 2025 Forest River Sandpiper 3660MB requires a capable tow vehicle. and a tongue weight of 1,460 pounds that your hitch must support. Make sure your tow vehicle is rated for the 11,500-lb GVWR when fully loaded with gear and water.
At the $105,000 price point, this Fifth Wheel caters to buyers who want elevated quality and are willing to invest in their travel lifestyle for years to come. If you already own a heavy-duty truck, the 2025 Forest River Sandpiper 3660MB transforms it into the tow vehicle for one of the most spacious and comfortable towable RV experiences available.
For 2025, the 2025 Forest River Sandpiper 3660MB continues to demonstrate why Forest River remains a respected name in the RV industry. It delivers a compelling combination of comfort, capability, and craftsmanship that holds up under real-world scrutiny.
The 2025 Forest River Sandpiper 3660MB represents the gold standard in fifth wheel design, combining innovative floor plans with construction quality that lasts for decades.
The 94-gallon fresh water system, combined with 53/38-gallon gray/black tanks, supports extended boondocking. Dual AC systems providing 13,500 BTU of cooling and a 16,000 BTU furnace ensure comfort in any climate.
Premium construction includes a fully enclosed and heated underbelly, aluminum frame, and seamless TPO roof with limited lifetime warranty. At $105,000, the 2025 Forest River Sandpiper 3660MB delivers exceptional value for this level of quality and comfort.