Fifth Wheel
Keystone RV Avalanche 366mb
Compare specs across all model years (2018–2021)
4
Model Years
8
Sleeps
39' 4"
Length
15,341
Avg GVWR
Our Recommendation
Which Year Should You Buy?
2019 Avalanche 366mb
Best Choice
Highest Mint Score (29.4).
What Changed Year-Over-Year
2019
2020
Capacity Upgrade
Sleeping capacity increased from 7 to 8 with layout improvements.
2018
2019
Weight Increase
GVWR increased from 14,865 to 15,500 lbs (635 lbs heavier).
All Model Years
2021
2021 Keystone RV Avalanche 366mb
29.2
15,500 lbs GVWR
2,690 lbs Hitch
39' 4"
Sleeps 8
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2020
2020 Keystone RV Avalanche 366mb
28.7
15,500 lbs GVWR
2,690 lbs Hitch
39' 4"
Sleeps 8
↑ Sleeps 1 more than 2019
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Best Value
2019
2019 Keystone RV Avalanche 366mb
29.4
15,500 lbs GVWR
2,690 lbs Hitch
39' 10"
Sleeps 7
↑ 635 lbs heavier than 2018
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Check Towing
2018
2018 Keystone RV Avalanche 366mb
28.9
14,865 lbs GVWR
2,690 lbs Hitch
39' 10"
Sleeps 7
Original model year
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Can Your Vehicle Tow the Avalanche 366mb?
Enter your truck specs to see if any of these model years fit your towing capacity—and which year gives you the most safety margin.
Tip: Click a year to see the full specs, tow guidance, and recommended gear for that model year.
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