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Forest River Flagstaff Shamrock 21SS

Hybridbuilt 2010–23Better build tierCommon on the used market
WHAT ONE COSTS
$26,300est. used (2023, 3 yr old)

Sticker was $40,835 in 2022. Out of production since 2023, so the used market is the only way to buy one. Estimate assumes a 2023 unit.

WHAT IT WEIGHS BEHIND YOUR TRUCK
6,674 lbno dry weight published: its rating stands in
You want a tow rating around7,420 lb (10% margin)
GVWR (the sticker maximum)6,674 lb
WHICH TOW VEHICLES IT FITS: 60 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 21SS's published weights held steady.

VEHICLETOW RATINGVERDICT
Chevrolet Colorado / GMC Canyon (2.7 Turbo HO, tow pkg) '23-267,700 lbfits, loaded, with 10% margin
Chevrolet Colorado / GMC Canyon (2.8 Duramax) '15-227,700 lbfits, loaded, with 10% margin
Chevrolet Silverado / GMC Sierra 1500 (6.2 V8, max tow) '19-2613,300 lbfits, loaded, with 10% margin
Chevrolet Silverado / GMC Sierra 2500HD (Duramax, max tow) '24-2622,500 lbfits, loaded, with 10% margin
Chevrolet Silverado / GMC Sierra 2500HD (Duramax) '20-2318,510 lbfits, loaded, with 10% margin
Chevrolet Silverado / GMC Sierra 2500HD (Duramax) '11-1918,100 lbfits, loaded, with 10% margin
Chevrolet Silverado / GMC Sierra 3500HD (Duramax DRW, gooseneck) '20-2636,000 lbfits, loaded, with 10% margin
Chevrolet Silverado / GMC Sierra 3500HD (Duramax DRW, gooseneck) '11-1923,300 lbfits, loaded, with 10% margin
Chevrolet Silverado 1500 (max tow) '14-1812,500 lbfits, loaded, with 10% margin
Chevrolet Silverado EV (4WT) '24-2612,500 lbfits, loaded, with 10% margin
Chevrolet Suburban (5.3 V8, max tow) '21-268,300 lbfits, loaded, with 10% margin
Chevrolet Tahoe (5.3 V8, max tow) '21-268,400 lbfits, loaded, with 10% margin
Dodge Durango (5.7 / 6.4 Hemi, tow pkg) '14-268,700 lbfits, loaded, with 10% margin
Ford Expedition (3.5 EcoBoost, tow pkg) '25-269,600 lbfits, loaded, with 10% margin
Ford Expedition (3.5 EcoBoost, tow pkg) '18-249,300 lbfits, loaded, with 10% margin
Ford F-150 (3.5 EcoBoost, max tow) '24-2613,500 lbfits, loaded, with 10% margin
Ford F-150 (3.5 EcoBoost, max tow) '15-2013,200 lbfits, loaded, with 10% margin
Ford F-150 (3.5 EcoBoost, max tow) '21-2314,000 lbfits, loaded, with 10% margin
Ford F-150 (3.5 EcoBoost, max tow) '11-1411,300 lbfits, loaded, with 10% margin
Ford F-150 Lightning (max trailer tow) '22-2610,000 lbfits, loaded, with 10% margin
Ford F-250 Super Duty (6.7 diesel, gooseneck) '20-2222,800 lbfits, loaded, with 10% margin
Ford F-250 Super Duty (6.7 diesel, tow pkg) '17-1918,000 lbfits, loaded, with 10% margin
Ford F-250 Super Duty (6.7 diesel) '11-1616,600 lbfits, loaded, with 10% margin
Ford F-250 Super Duty (6.7 HO diesel, gooseneck) '23-2623,000 lbfits, loaded, with 10% margin
Ford F-350 Super Duty (6.7 diesel DRW, gooseneck) '17-1932,500 lbfits, loaded, with 10% margin
Ford F-350 Super Duty (6.7 diesel DRW, gooseneck) '20-2237,000 lbfits, loaded, with 10% margin
Ford F-350 Super Duty (6.7 diesel DRW, gooseneck) '11-1621,600 lbfits, loaded, with 10% margin
Ford F-350 Super Duty (6.7 HO diesel DRW, gooseneck) '23-2638,000 lbfits, loaded, with 10% margin
Ford F-450 Super Duty (6.7 HO diesel DRW, gooseneck) '23-2640,000 lbfits, loaded, with 10% margin
Ford Ranger (2.3 EcoBoost, tow pkg) '19-237,500 lbfits, loaded, with 10% margin
Ford Ranger (2.7 EcoBoost, tow pkg) '24-267,500 lbfits, loaded, with 10% margin
GMC Hummer EV Pickup '22-267,500 lbfits, loaded, with 10% margin
GMC Sierra EV '24-2612,000 lbfits, loaded, with 10% margin
GMC Yukon / Yukon XL (5.3 V8, max tow) '21-268,400 lbfits, loaded, with 10% margin
Jeep Gladiator (3.6 V6, max tow) '20-267,700 lbfits, loaded, with 10% margin
Jeep Grand Wagoneer (Hurricane, max tow) '22-269,850 lbfits, loaded, with 10% margin
Jeep Wagoneer (Hurricane, max tow) '22-2610,000 lbfits, loaded, with 10% margin
Land Rover Defender '20-268,201 lbfits, loaded, with 10% margin
Land Rover Discovery '17-268,201 lbfits, loaded, with 10% margin
Lexus GX 550 (tow pkg) '24-269,096 lbfits, loaded, with 10% margin
Lexus LX 600 '22-268,000 lbfits, loaded, with 10% margin
Mercedes-Benz Sprinter '19-267,500 lbfits, loaded, with 10% margin
Nissan Armada (3.5 twin-turbo, tow pkg) '25-268,500 lbfits, loaded, with 10% margin
Nissan Armada (tow pkg) '17-248,500 lbfits, loaded, with 10% margin
Nissan Titan (5.6 V8, tow pkg) '17-249,760 lbfits, loaded, with 10% margin
Nissan Titan XD (Cummins diesel) '16-1912,710 lbfits, loaded, with 10% margin
Ram 1500 (3.0 Hurricane, max tow) '25-2611,610 lbfits, loaded, with 10% margin
Ram 1500 (5.7 Hemi eTorque, max tow) '19-2412,750 lbfits, loaded, with 10% margin
Ram 1500 (5.7 Hemi, max tow) '11-1810,620 lbfits, loaded, with 10% margin
Ram 2500 (6.7 Cummins HO) '19-2620,000 lbfits, loaded, with 10% margin
Ram 2500 (6.7 Cummins) '11-1817,980 lbfits, loaded, with 10% margin
Ram 3500 (6.7 Cummins DRW, gooseneck) '13-1831,210 lbfits, loaded, with 10% margin
Ram 3500 (6.7 Cummins HO DRW, gooseneck) '25-2636,610 lbfits, loaded, with 10% margin
Ram 3500 (6.7 Cummins HO DRW, gooseneck) '19-2437,090 lbfits, loaded, with 10% margin
Rivian R1S '22-267,700 lbfits, loaded, with 10% margin
Rivian R1T '22-2611,000 lbfits, loaded, with 10% margin
Tesla Cybertruck '24-2611,000 lbfits, loaded, with 10% margin
Toyota Sequoia (i-Force Max, tow pkg) '23-269,520 lbfits, loaded, with 10% margin
Toyota Tundra (5.7 V8, tow pkg) '11-2110,200 lbfits, loaded, with 10% margin
Toyota Tundra (i-Force Max, tow pkg) '22-2612,000 lbfits, loaded, with 10% margin
The 35it doesn't fit

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

THE SPECS
Length27.2 ft
GVWR6,674 lb
Dry weightnot published
Sleeps8
Slide-outs1
Axles2

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

WHERE PEOPLE SLEEP
  • 2× Front and rear tent ends(Permanent)—
  • 2× Slide sofa and dinette(Convertible)—
HOW IT'S BUILT: 5/5
WallsAzdel composite
FrameAluminum
RoofWalk-on
UnderbellyEnclosed

Forest River (Better tier): Flagstaff

YEAR BY YEAR: WHAT CHANGED
  • 2010Introduced
  • 2019Fresh tank 43 to 58 gal
  • 2023Discontinued
FINDING ONE

Common: usually several for sale within a day’s drive. Why: Forest River is a volume manufacturer; 14-year production run; an uncommon body style. Estimated from build volume and production span, not a count of live listings.

OUR TAKE

The volume single-slide Shamrock for over a decade.

OTHER FLAGSTAFF SHAMROCK FLOORPLANS
17 · 3,854 lb · sleeps 6183 · 4,820 lb · sleeps 819 · 5,714 lb · sleeps 821BD · 6,638 lb · sleeps 621BH · 4,856 lb · sleeps 721DK · 5,016 lb · sleeps 621RS · 5,450 lb · sleeps 8231KSS · 6,558 lb · sleeps 8233 · 5,978 lb · sleeps 10233S · 6,678 lb · sleeps 10235S · 6,926 lb · sleeps 823RS · 6,145 lb · sleeps 923SS · 6,602 lb · sleeps 825RS · 6,502 lb · sleeps 8the whole line →
Find one for sale

Live listings for the 21SS 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 Flagstaff Shamrock line ↗

Is the 21SS 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.