Grand Design Solitude 366DEN

Name: Grand Design Solitude 366DEN
Brand: Grand Design

Fifth wheelbuilt 2015–16Better build tierPatient search on the used market

WHAT ONE COSTS

$45,300est. used (2016, 10 yr old)

Sticker was $85,094 in 2016. Out of production since 2016, so the used market is the only way to buy one. Estimate assumes a 2016 unit.

WHAT IT WEIGHS BEHIND YOUR TRUCK

~15,500 lbestimated as towed, for 2 people

dry weight 14,250 lb + fresh water (54 gal, full) 450 lb + propane + battery 200 lb + gear for 2 600 lb. Brochure dry weight omits water, propane, batteries and your gear; this estimate doesn't.

You want a tow rating around17,225 lb (10% margin)

GVWR (the sticker maximum)16,000 lb

Tongue weight, loaded~3,481 lb (22%)

WHICH TOW VEHICLES IT FITS: 18 OF 95

Judged the way the app judges: estimated loaded weight against each vehicle's rating less a 10% margin, per model year, because the 366DEN's published weights held steady. Fifth wheels also need a pickup bed and are held to the fifth-wheel rating where published.

VEHICLE	TOW RATING	VERDICT
Chevrolet Silverado / GMC Sierra 2500HD (Duramax, max tow) '24-26	22,500 lb	fits, loaded, with 10% margin
Chevrolet Silverado / GMC Sierra 2500HD (Duramax) '20-23	18,510 lb	fits, loaded, with 10% margin
Chevrolet Silverado / GMC Sierra 2500HD (Duramax) '11-19	18,100 lb	fits, loaded, with 10% margin
Chevrolet Silverado / GMC Sierra 3500HD (Duramax DRW, gooseneck) '20-26	36,000 lb	fits, loaded, with 10% margin
Chevrolet Silverado / GMC Sierra 3500HD (Duramax DRW, gooseneck) '11-19	23,300 lb	fits, loaded, with 10% margin
Ford F-250 Super Duty (6.7 diesel, gooseneck) '20-22	22,800 lb	fits, loaded, with 10% margin
Ford F-250 Super Duty (6.7 diesel, tow pkg) '17-19	18,000 lb	fits, loaded, with 10% margin
Ford F-250 Super Duty (6.7 HO diesel, gooseneck) '23-26	23,000 lb	fits, loaded, with 10% margin
Ford F-350 Super Duty (6.7 diesel DRW, gooseneck) '17-19	32,500 lb	fits, loaded, with 10% margin
Ford F-350 Super Duty (6.7 diesel DRW, gooseneck) '20-22	37,000 lb	fits, loaded, with 10% margin
Ford F-350 Super Duty (6.7 diesel DRW, gooseneck) '11-16	21,600 lb	fits, loaded, with 10% margin
Ford F-350 Super Duty (6.7 HO diesel DRW, gooseneck) '23-26	38,000 lb	fits, loaded, with 10% margin
Ford F-450 Super Duty (6.7 HO diesel DRW, gooseneck) '23-26	40,000 lb	fits, loaded, with 10% margin
Ram 2500 (6.7 Cummins HO) '19-26	20,000 lb	fits, loaded, with 10% margin
Ram 2500 (6.7 Cummins) '11-18	17,980 lb	fits, loaded, with 10% margin
Ram 3500 (6.7 Cummins DRW, gooseneck) '13-18	31,210 lb	fits, loaded, with 10% margin
Ram 3500 (6.7 Cummins HO DRW, gooseneck) '25-26	36,610 lb	fits, loaded, with 10% margin
Ram 3500 (6.7 Cummins HO DRW, gooseneck) '19-24	37,090 lb	fits, loaded, with 10% margin

The 77it doesn't fit

Chevrolet Colorado / GMC Canyon (2.7 Turbo HO, tow pkg) '23-26: over by ~8,570 lb loaded
Chevrolet Colorado / GMC Canyon (2.8 Duramax) '15-22: over by ~8,570 lb loaded
Chevrolet Silverado / GMC Sierra 1500 (6.2 V8, max tow) '19-26: over by ~6,230 lb loaded
Chevrolet Silverado 1500 (max tow) '14-18: over by ~5,060 lb loaded
Chevrolet Silverado EV (4WT) '24-26: over by ~4,250 lb loaded
Chevrolet Suburban (5.3 V8, max tow) '21-26: no pickup bed (cannot hitch a fifth wheel)
Chevrolet Tahoe (5.3 V8, max tow) '21-26: no pickup bed (cannot hitch a fifth wheel)
Chevrolet Traverse (tow pkg) '18-26: no pickup bed (cannot hitch a fifth wheel)
Chrysler Pacifica '17-26: no pickup bed (cannot hitch a fifth wheel)
Dodge Durango (5.7 / 6.4 Hemi, tow pkg) '14-26: no pickup bed (cannot hitch a fifth wheel)
Ford Bronco 4-dr (2.7 EcoBoost, tow pkg) '21-26: no pickup bed (cannot hitch a fifth wheel)
Ford Expedition (3.5 EcoBoost, tow pkg) '25-26: no pickup bed (cannot hitch a fifth wheel)
Ford Expedition (3.5 EcoBoost, tow pkg) '18-24: no pickup bed (cannot hitch a fifth wheel)
Ford Explorer (3.0 EcoBoost, tow pkg) '20-26: no pickup bed (cannot hitch a fifth wheel)
Ford F-150 (3.5 EcoBoost, max tow) '24-26: over by ~5,780 lb loaded
Ford F-150 (3.5 EcoBoost, max tow) '15-20: over by ~4,790 lb loaded
Ford F-150 (3.5 EcoBoost, max tow) '21-23: over by ~2,900 lb loaded
Ford F-150 (3.5 EcoBoost, max tow) '11-14: over by ~5,330 lb loaded
Ford F-150 Lightning (max trailer tow) '22-26: over by ~6,500 lb loaded
Ford F-250 Super Duty (6.7 diesel) '11-16: over by ~560 lb loaded
Ford Maverick (2.0 EcoBoost, 4K tow pkg) '22-26: over by ~11,900 lb loaded
Ford Ranger (2.3 EcoBoost, tow pkg) '19-23: over by ~8,750 lb loaded
Ford Ranger (2.7 EcoBoost, tow pkg) '24-26: over by ~8,750 lb loaded
Ford Transit (HD tow pkg) '15-26: no pickup bed (cannot hitch a fifth wheel)
GMC Acadia (tow pkg) '20-26: no pickup bed (cannot hitch a fifth wheel)
GMC Hummer EV Pickup '22-26: over by ~8,750 lb loaded
GMC Sierra EV '24-26: over by ~4,700 lb loaded
GMC Yukon / Yukon XL (5.3 V8, max tow) '21-26: no pickup bed (cannot hitch a fifth wheel)
Honda Odyssey '18-26: no pickup bed (cannot hitch a fifth wheel)
Honda Passport (AWD) '19-26: no pickup bed (cannot hitch a fifth wheel)
Honda Pilot (AWD, tow pkg) '16-26: no pickup bed (cannot hitch a fifth wheel)
Honda Ridgeline (AWD) '17-26: over by ~11,000 lb loaded
Hyundai Palisade (tow pkg) '20-26: no pickup bed (cannot hitch a fifth wheel)
Hyundai Santa Cruz (2.5T AWD) '22-26: over by ~11,000 lb loaded
Jeep Gladiator (3.6 V6, max tow) '20-26: over by ~8,570 lb loaded
Jeep Grand Cherokee (5.7 Hemi) '11-21: no pickup bed (cannot hitch a fifth wheel)
Jeep Grand Cherokee (WL, tow pkg) '22-26: no pickup bed (cannot hitch a fifth wheel)
Jeep Grand Cherokee L (5.7 Hemi) '21-26: no pickup bed (cannot hitch a fifth wheel)
Jeep Grand Wagoneer (Hurricane, max tow) '22-26: no pickup bed (cannot hitch a fifth wheel)
Jeep Wagoneer (Hurricane, max tow) '22-26: no pickup bed (cannot hitch a fifth wheel)
Jeep Wrangler Unlimited 4-dr (tow pkg) '18-26: no pickup bed (cannot hitch a fifth wheel)
Kia Telluride (tow pkg) '20-26: no pickup bed (cannot hitch a fifth wheel)
Land Rover Defender '20-26: no pickup bed (cannot hitch a fifth wheel)
Land Rover Discovery '17-26: no pickup bed (cannot hitch a fifth wheel)
Lexus GX 550 (tow pkg) '24-26: no pickup bed (cannot hitch a fifth wheel)
Lexus LX 600 '22-26: no pickup bed (cannot hitch a fifth wheel)
Mazda CX-90 (3.3 turbo, tow pkg) '24-26: no pickup bed (cannot hitch a fifth wheel)
Mercedes-Benz Sprinter '19-26: no pickup bed (cannot hitch a fifth wheel)
Nissan Armada (3.5 twin-turbo, tow pkg) '25-26: no pickup bed (cannot hitch a fifth wheel)
Nissan Armada (tow pkg) '17-24: no pickup bed (cannot hitch a fifth wheel)
Nissan Frontier (3.8 V6, tow pkg) '22-26: over by ~9,065 lb loaded
Nissan Pathfinder (tow pkg) '22-26: no pickup bed (cannot hitch a fifth wheel)
Nissan Titan (5.6 V8, tow pkg) '17-24: over by ~6,715 lb loaded
Nissan Titan XD (Cummins diesel) '16-19: over by ~4,060 lb loaded
Ram 1500 (3.0 Hurricane, max tow) '25-26: over by ~5,050 lb loaded
Ram 1500 (5.7 Hemi eTorque, max tow) '19-24: over by ~4,025 lb loaded
Ram 1500 (5.7 Hemi, max tow) '11-18: over by ~5,940 lb loaded
Ram ProMaster '14-26: no pickup bed (cannot hitch a fifth wheel)
Rivian R1S '22-26: no pickup bed (cannot hitch a fifth wheel)
Rivian R1T '22-26: over by ~5,600 lb loaded
Subaru Ascent '19-26: no pickup bed (cannot hitch a fifth wheel)
Subaru Outback (XT / Wilderness) '20-26: no pickup bed (cannot hitch a fifth wheel)
Tesla Cybertruck '24-26: over by ~5,600 lb loaded
Tesla Model X (tow pkg) '16-26: no pickup bed (cannot hitch a fifth wheel)
Tesla Model Y (tow pkg) '21-26: no pickup bed (cannot hitch a fifth wheel)
Toyota 4Runner (4.0 V6) '11-24: no pickup bed (cannot hitch a fifth wheel)
Toyota 4Runner (i-Force Max) '25-26: no pickup bed (cannot hitch a fifth wheel)
Toyota Grand Highlander (i-Force Max) '24-26: no pickup bed (cannot hitch a fifth wheel)
Toyota Highlander (tow pkg) '20-26: no pickup bed (cannot hitch a fifth wheel)
Toyota Land Cruiser (i-Force Max) '24-26: no pickup bed (cannot hitch a fifth wheel)
Toyota Sequoia (i-Force Max, tow pkg) '23-26: no pickup bed (cannot hitch a fifth wheel)
Toyota Sienna '21-26: no pickup bed (cannot hitch a fifth wheel)
Toyota Tacoma (i-Force Max, tow pkg) '24-26: over by ~9,650 lb loaded
Toyota Tacoma (V6, tow pkg) '16-23: over by ~9,380 lb loaded
Toyota Tundra (5.7 V8, tow pkg) '11-21: over by ~6,320 lb loaded
Toyota Tundra (i-Force Max, tow pkg) '22-26: over by ~4,700 lb loaded
Volkswagen Atlas (tow pkg) '18-26: no pickup bed (cannot hitch a fifth wheel)

These verdicts assume 2 people aboard with typical gear. See the margin for your truck and your crew →

THE SPECS

Length40.3 ft

Height (incl. A/C)12.9 ft

Width8.4 ft

GVWR16,000 lb

Dry weight14,250 lb

Dry tongue weight3,200 lb

Sleeps5

Slide-outs5

Axles2

Fresh water54 gal

Grey water75 gal

Black water78 gal

Awning16 ft

A missing row means the maker never published that figure: unknown, not zero.

WHERE PEOPLE SLEEP

1× Front queen bed(Permanent)60×80
1× Tri-fold hide-a-bed sofa(Convertible)—
1× Dinette converts to a bed(Convertible)—

HOW IT'S BUILT: 4/5

WallsLaminated fiberglass

FrameAluminum

RoofWalk-on

UnderbellyEnclosed

Grand Design (Better tier): Solitude is Grand Design's full-profile flagship: R-11 welded-aluminum laminated walls, 101" widebody chassis, MORryde independent suspension and 17.5" H-rated tires — genuine full-time-capable construction.

YEAR BY YEAR: WHAT CHANGED

2015Introduced in the first Solitude lineup
2016Discontinued

FINDING ONE

Patient search: weeks of watching, and probably some travel. Why: only 2 model years; 10 years out of production. Estimated from build volume and production span, not a count of live listings.

OUR TAKE

Early rear-den Solitude from the launch era. MSRP not published in surviving sources.

OTHER SOLITUDE FLOORPLANS

2930RL · 15,000 lb · sleeps 2 305RE · 16,000 lb · sleeps 4 310GK · 19,000 lb · sleeps 4 3330RE · 16,800 lb · sleeps 6 344GK · 16,800 lb · sleeps 6 345GK · 16,800 lb · sleeps 4 3460FL · 16,800 lb · sleeps 6 3540GK · 16,800 lb · sleeps 4 3550BH · 16,800 lb · sleeps 8 370DV · 19,000 lb · sleeps 4 372WB · 16,800 lb · sleeps 4 373FB · 16,800 lb · sleeps 4 3740BH · 16,800 lb · sleeps 8 374TH · 20,000 lb · sleeps 6 the whole line →

Find one for sale

Live listings for the 366DEN on the big marketplaces. Each search opens pre-filled with this exact floorplan:

RV Trader ↗Camping World ↗FB Marketplace ↗Google ↗

Inventory varies by site and day. Slim pickings? search the whole Solitude line ↗

Is the 366DEN your #1, or just a spec sheet?

These are the facts. Whether it beats the other six thousand rigs for you depends on what you care about. Set your priorities as sliders, switch on your hard limits, and watch the whole market re-rank around them. Every exclusion explained, every margin shown.

See where it ranks for you →

Data compiled from dealer and aggregator listings, retrieved 2026-07.