Forest River Sierra RVs for sale
Featured listings
New 2025 Forest River
Sierra 3990FL
Middle Point, OH
$66,000
New 2025 Forest River
Sierra 3990FL
Claremore, OK
$69,999
Used 2024 Forest River
SIERRA 3990FL
Dorothy, NJ
$57,500
Used 2021 Forest River
SIERRA 3990FL
Newington, CT
$47,500
Used 2018 Forest River
SIERRA 3990FL
Arabi, LA
$45,000
New 2025 Forest River Rv
Sierra 3990FL
Bryan, TX
$68,950
32 results
Premium
Used 2025 Forest River SIERRA 3990FL
Buford, GA
Camping World (Buford, GA)
$70,688
Premium
3 A/C!
New 2026 Forest River Rv Sierra 3990FL
Loganville, GA
Camp Rite RV Sales
$69,999
Premium
Negotiable
History report
Used 2024 Forest River SIERRA 3990FL
Dorothy, NJ
Private seller
$57,500
Premium
New 2026 Forest River SIERRA 3990FL
Mesa, AZ
General RV Center - Mesa
$79,999
New 2026 Forest River Sierra 3990FL
Greencastle, PA
Keystone RV Center
$74,981
New 2027 Forest River Rv Sierra 3990FL
Odessa, TX
Ron Hoover RV & Marine - Odessa
$123,961
New 2026 Forest River SIERRA 3990FL
Akron, OH
Camping World (Akron, OH)
$74,397
CALL 512-930-4922 FOR INFO!
New 2026 Forest River Rv Sierra 3990FL
Georgetown, TX
Ron Hoover RV & Marine - Georgetown
$77,997
New 2026 Forest River Rv Sierra 3990FL
San Antonio, TX
Ron Hoover RV & Marine - San Antonio
$77,997
New 2026 Forest River SIERRA 3990FL
Deforest, WI
Camping World (Deforest, WI)
$68,698
New 2026 Forest River SIERRA 3990FL
Spring, TX
Camping World (Spring, TX)
$70,524
New 2026 Forest River SIERRA 3800RK
Sweetwater, TX
Family RV Center
$76,992
New 2026 Forest River SIERRA 3990FL
Jackson, TN
Camping World (Jackson, TN)
$79,598
New 2025 Forest River Rv Sierra 3990FL
Bryan, TX
T&S RV & Sport LLC - Bryan
$68,950
5 year trusted partner
New 2027 Forest River Rv Sierra 3990FL
Appleton, WI
Markquart RV - Appleton
$79,795
Used 2024 Forest River SIERRA 3990FL
Harrisburg, PA
Camping World (Harrisburg, PA)
$59,999
ZERO DEALER FEES FTC COMPLIANT
New 2026 Forest River Rv Sierra 3990FL
Myrtle Beach, SC
Recreation USA Myrtle Beach
$71,982
On Sale Now
New 2026 Forest River Rv Sierra 3990FL
Selinsgrove, PA
Salem RV
$68,995
Gorgeous Front Living
New 2026 Forest River Rv Sierra 3990FL
Caldwell, ID
Bobby Combs RV - Caldwell
$74,980
Price reduced
New 2026 Forest River Rv Sierra 3990FL
Conroe, TX
Fun Town RV - Conroe
$77,734
Price reduced
New 2026 Forest River Rv Sierra 3990FL
Rockwall, TX
Fun Town RV - Dallas
$71,777
Price reduced
New 2026 Forest River Rv Sierra 3990FL
Anna, IL
Fun Town RV - Anna
$72,765
Price reduced
New 2026 Forest River Rv Sierra 3990FL
Jackson, MI
Fun Town RV - Jackson
$63,265
New 2026 Forest River Rv Sierra 3990FL
Springfield, IL
Colman's RV
$64,990
Price reduced
New 2026 Forest River Sierra 3990FL
Muskogee, OK
Rocky Ridge RV - Muskogee
$73,793
New 2026 Forest River Rv Sierra 3990FL
Ham Lake, MN
North Country RV
$71,345
The 2021 Sierra 3990FL is a five-slide RV that offers great storage and residential-style comfort.
History report
Used 2021 Forest River Sierra 391FLRB
Newington, CT
Pop RVs
$50,600
5 year trusted partner
NO HIDDEN FEES
New 2025 Forest River Sierra 3990FL
Middle Point, OH
Huggy Bear RV
$66,000
Used 2025 Forest River Rv Sierra 3990FL
S. Okeechobee, FL
Chesaco RV - Okeechobee
$94,855
New 2025 Forest River Sierra 3990FL
Claremore, OK
Ron Hoover RV & Marine - Tulsa
$69,999
Sell on RV Trader
Earn $1,000's more
Free RV valuation
List in 5 minutes
Safe & secure with dedicated support
Premium
Negotiable
Used 2021 Forest River SIERRA 3990FL
Newington, CT
Private seller
$47,500
Premium
Used 2018 Forest River SIERRA 3990FL
Arabi, LA
Private seller
$45,000
RV Trader disclaimer: The information provided for each listing is supplied by the seller and/or other third parties. RVTrader.com is not responsible for the accuracy of the information. Please refer to the RV Trader Terms of Use for further information.
Vehicle photos displayed on this page may be AI-enhanced. AI-generated content isn't always correct, so please contact the seller to verify all details.
