Fifth Wheel
Grand Design RV Solitude 378mbs
Compare specs across all model years (2021–2025)
5
Model Years
7
Sleeps
40' 2"
Length
17,040
Avg GVWR
Our Recommendation
Which Year Should You Buy?
2025 Solitude 378mbs
Best Choice
Highest Mint Score (29.9). Most recent model year with latest updates.
What Changed Year-Over-Year
2024
2025
Weight Increase
GVWR increased from 16,800 to 18,000 lbs (1,200 lbs heavier).
2023
2024
Length Increased
Length changed from 40' 2" to 41' 9".
All Model Years
Best Value
2025
2025 Grand Design RV Solitude 378mbs
29.9
18,000 lbs GVWR
2,686 lbs Hitch
40' 2"
Sleeps 7
↑ 1,200 lbs heavier than 2024
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2024
2024 Grand Design RV Solitude 378mbs
29.1
16,800 lbs GVWR
2,686 lbs Hitch
41' 9"
Sleeps 7
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2023
2023 Grand Design RV Solitude 378mbs
29.1
16,800 lbs GVWR
2,686 lbs Hitch
40' 2"
Sleeps 7
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Check Towing
2022
2022 Grand Design RV Solitude 378mbs
29.1
16,800 lbs GVWR
2,686 lbs Hitch
40' 2"
Sleeps 7
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Check Towing
2021
2021 Grand Design RV Solitude 378mbs
29.1
16,800 lbs GVWR
2,686 lbs Hitch
40' 2"
Sleeps 7
Original model year
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Can Your Vehicle Tow the Solitude 378mbs?
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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