Toy Hauler
Grand Design RV Momentum M-Class 381m
Compare specs across all model years (2018–2022)
5
Model Years
8
Sleeps
42' 9"
Length
20,000
Avg GVWR
Our Recommendation
Which Year Should You Buy?
2018 Momentum M-Class 381m
Best Choice
Lightest GVWR (20,000 lbs) makes it towable by more vehicles. Highest Mint Score (31.1).
What Changed Year-Over-Year
2021
2022
Capacity Change
Sleeping capacity changed from 9 to 7.
2018
2019
Capacity Upgrade
Sleeping capacity increased from 7 to 9 with layout improvements.
All Model Years
2022
2022 Grand Design RV Momentum M-Class 381m
30.9
20,000 lbs GVWR
2,800 lbs Hitch
42' 9"
Sleeps 7
↓ Sleeps 2 fewer than 2021
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2021
2021 Grand Design RV Momentum M-Class 381m
29.4
20,000 lbs GVWR
2,800 lbs Hitch
42' 9"
Sleeps 9
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2020
2020 Grand Design RV Momentum M-Class 381m
28.9
20,000 lbs GVWR
2,800 lbs Hitch
42' 9"
Sleeps 9
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Check Towing
2019
2019 Grand Design RV Momentum M-Class 381m
28.9
20,000 lbs GVWR
2,800 lbs Hitch
42' 9"
Sleeps 9
↑ Sleeps 2 more than 2018
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Check Towing
Best Value
2018
2018 Grand Design RV Momentum M-Class 381m
31.1
20,000 lbs GVWR
2,800 lbs Hitch
42' 9"
Sleeps 7
Original model year
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Check Towing
Can Your Vehicle Tow the Momentum M-Class 381m?
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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