2024 Grand Design Momentum 399TH vs 2024 Grand Design Momentum G-Class 25G

Both the 2024 Grand Design Momentum 399TH and the 2024 Grand Design Momentum G-Class 25G have loyal followings, and for good reason. Here's an objective look at how they measure up.

Specifications Comparison

Specification2024 Grand Design Momentum 399TH2024 Grand Design Momentum G-Class 25GAdvantage
CategoryToy HaulerToy Hauler
Year20242024Tie
Length28 ft30 ft
Width8 ft8.5 ft
Height12.5 ft13 ft
Dry Weight8,300 lbs10,100 lbs
GVWR11,900 lbs14,200 lbs
Sleeping Capacity962024 Grand Design Momentum 399TH
Fresh Water68 gal95 gal2024 Grand Design Momentum G-Class 25G
Gray Water70 gal60 gal2024 Grand Design Momentum 399TH
Black Water50 gal35 gal2024 Grand Design Momentum 399TH
Fuel Capacity48 gal34 gal2024 Grand Design Momentum 399TH
Horsepower
Engine
Slide-Outs00
Solar200 W250 W2024 Grand Design Momentum G-Class 25G
Battery150 Ah100 Ah2024 Grand Design Momentum 399TH
Inverter2,500 W3,000 W2024 Grand Design Momentum G-Class 25G
MSRP$61,000$41,0002024 Grand Design Momentum G-Class 25G

Detailed Comparison

Both the 2024 Grand Design Momentum 399TH and the 2024 Grand Design Momentum G-Class 25G have loyal followings, and for good reason. Here's an objective look at how they measure up.

The Grand Design Momentum 399TH measures 28.0 ft in length at 8,300 lbs, compared to the Grand Design Momentum G-Class 25G's 30.0 ft and 10,100 lbs. GVWR ratings sit at 11,900 lbs and 14,200 lbs respectively.

The Grand Design Momentum 399TH sleeps 9 while the Grand Design Momentum G-Class 25G accommodates 6.

For boondocking enthusiasts, tank sizes matter. Fresh water capacity goes to the Grand Design Momentum G-Class 25G at 95 gallons versus 68 gallons. Solar-wise, you get 200W on the Grand Design Momentum 399TH and 250W on the Grand Design Momentum G-Class 25G. Battery banks are 150 Ah and 100 Ah.

At $61,000 MSRP for the Grand Design Momentum 399TH and $41,000 for the Grand Design Momentum G-Class 25G, the Grand Design Momentum G-Class 25G saves you $20,000.

If you're traveling with a family, look for the model with more sleeping positions and better storage. Boondockers: look at the fresh water capacity and solar/battery systems — they determine how long you can stay out. For the full-time RV lifestyle, every gallon of tank capacity and every inch of counter space counts.

Take these specs as a starting point, then go see them in person — there's no substitute for stepping inside.

Individual Overviews

2024 Grand Design Momentum 399TH

  • Category: Toy Hauler
  • Length: 28 ft
  • Weight: 8,300 lbs
  • Sleeps: 9
  • MSRP: $61,000
View Full Specs

2024 Grand Design Momentum G-Class 25G

  • Category: Toy Hauler
  • Length: 30 ft
  • Weight: 10,100 lbs
  • Sleeps: 6
  • MSRP: $41,000
View Full Specs