01 What makes it unique
The 3800RK is Sandpiper’s cook’s plan, and the longest coach in the line. The “RK” marks a residential rear kitchen spread across the back wall — a stainless package, the standard 16-cubic-foot 12-volt refrigerator, abundant counter space and a 30-inch over-the-range microwave — with theater seating, a king front master and washer and dryer as standard (one of only two Sandpiper plans with the laundry included). Four slide-outs open the main level. At 44 feet 1 inch it is the longest coach in the line. It rides the full Sandpiper build: a cambered powder-coated frame, a single tandem 7,000-pound axle rating, an automatic electric level-up system and 200-watt solar.
Forest River lists a published 15,500-pound GVWR against the 12,849-pound dry weight, which leaves a 2,651-pound payload and a 2,405-pound dry pin, on tandem 7,000-pound axles. Two 15,000-BTU air conditioners (prepped for a third), a 60,000-BTU tankless water heater, a 40,000-BTU furnace, heated holding tanks, an 84-inch ceiling and a 50-inch smart television are standard, under dual 13-foot and 16-foot awnings.
At a starting MSRP around $96,000, with US street pricing well below the placard (commonly in the mid $70,000s), it is the rear-kitchen, couple’s Sandpiper. For a couple who cooks and wants a residential rear galley, theater seating, a king master and standard laundry in a full-size fifth wheel a tier below the luxury lines — and who tows with a properly rated three-quarter-ton or larger truck — the 3800RK is the cook’s plan.
02 Full specifications
Dimensions
- Exterior length
- 44' 1"
- Exterior width
- 8' 0"
- Exterior height
- 13' 4"
- Interior height
- 7' 0"
Weights
- Dry / unit base weight (UVW)
- 12,849 lbs
- GVWR (max loaded)
- 15,500 lbs
- Net cargo / payload (CCC)
- 2,651 lbs
- Dry pin (hitch) weight
- 2,405 lbs
Capacities
- Fresh water
- 50 gal
- Grey water
- 100 gal
- Black water
- 50 gal
- Refrigerator
- 16 cu ft
Construction
- Frame
- Cambered powder-coated frame · rust prohibitor · underbelly armor
- Walls
- Laminated sidewalls · R-10 2" sidewall · welded aluminum-framed vacuum-bonded
- Roof
- Full walk-on roof · 3/8" decking · 5" truss rafters
- Underbelly
- Underbelly armor · 12V heated holding tanks · enclosed
Running gear
- Axles
- 2 (7,000 lb tandem)
- Hitch
- Fifth-wheel (in-bed) · 2" accessory receiver (where available)
- Brakes
- Anti-lock (ABS) · Lippert auto-adjust
- Tires
- Goodyear Radial · upgraded aluminum rims · TPMS
Galley & bath
- Cooktop
- 3-burner gas range · 24" oven · 30" OTR microwave
- Refrigerator
- 16 cu ft
- A/C
- 30,000 BTU (dual 15K, prepped for 3rd)
- Water heater
- 60,000-BTU tankless · on-demand
Sleeping & layout
- Sleeps
- 4
- Slides
- 4
- Entries
- 1
- Awnings
- 2 (13' & 16')
- Primary bed
- King
03 The Sandpiper floorplan family
Sandpiper is Forest River's premium-mainstream full-size fifth wheel — a step below the Cedar Creek and Riverstone luxury lines and a cross-shop against Grand Design's Reflection and Keystone's Cougar. The 2026 retail fifth-wheel line runs to seven floorplans, and all seven are profiled here in full. The 3800RK on this page is highlighted; each other plan links to its own page.
| Floorplan | Nominal | Sleeps | Notable |
|---|---|---|---|
| 3710HBFB | 43 ft | 7 | Front bunkhouse, bath-and-a-half, rear bath |
| 3844QUAD | 43 ft | 7 | Quad bunks + island, outside kitchen, five slides |
| 3900HBLR | 43 ft | 4 | Rear living + mobile workstation, 2026 flagship |
| 4003MB | 43 ft | 8 | Middle bunkhouse, front master + rear living + loft |
| 4002FB | 43 ft | 6 | Two full baths + two bedrooms + loft, dual entry |
| 3990FL | 44 ft | 8 | Front living + loft-and-a-half, biggest payload |
| 3800RK | 44 ft | 4 | Rear kitchen, theater seating, washer/dryer standard |
Sandpiper is Forest River's premium-mainstream full-size fifth wheel — a step below the Cedar Creek and Riverstone luxury lines and a cross-shop against Grand Design's Reflection and Keystone's Cougar. The 2026 retail fifth-wheel line runs to seven floorplans, all profiled here; two further plans, the 3370RLS and 3550BH, are Dealer Stock Only and are listed on the hub but not profiled. Every plan rides on a cambered powder-coated frame with a single tandem 7,000-pound axle rating, Goodyear Radial tires with ABS and Lippert auto-adjust brakes, an automatic electric level-up system and 200-watt solar, and ships with a 16-cubic-foot 12-volt refrigerator, two 15,000-BTU air conditioners (prepped for a third), a 60,000-BTU tankless water heater, an 84-inch ceiling and a 50-inch smart television (65-inch on the 3900HBLR) as standard. Hitch weight, GVWR, UVW and CCC are published per plan on the Forest River factory pages, and each plan's UVW plus CCC equals its GVWR exactly. UVW is a factory estimated average; real loaded pin weights run higher — always weigh the loaded coach and confirm against your truck's payload and rear-axle ratings. Sandpiper is badge-engineered as the Sierra, built side-by-side on the same line with only the decals different.
04 What owners & reviewers report
Residential rear kitchen
A full galley across the back wall with a stainless package, a 16-cubic-foot 12-volt fridge and abundant counter space — the line’s kitchen-first plan.
Washer and dryer standard
One of only two Sandpiper plans (with the 3900HBLR) that includes the washer and dryer rather than just the prep.
Longest coach in the line
At 44 feet 1 inch it is the longest Sandpiper — a couple’s coach with theater seating and a king master, sleeping four.
Wants a three-quarter-ton+ truck
At over 44 feet on a 15,500-lb GVWR with tandem 7K axles, confirm a properly rated three-quarter-ton or larger truck’s payload and rear axle.
05 How it compares
The rear-living flagship — a rear great room with a mobile workstation instead of a rear kitchen.
Grand Design’s rear-living Reflection — the mainstream-luxury-FW couple’s cross-shop.
Forest River’s luxury rear-kitchen fifth wheel — a tier above, heavier and far pricier.