2025 Grand Design Solitude 390RK vs 2024 Forest River Sierra 391FLRB

Detailed Comparison

The 2025 Grand Design Solitude 390RK and 2024 Forest River Sierra 391FLRB represent two compelling choices for RV enthusiasts. Let's break down what sets them apart.

In terms of footprint, the Grand Design Solitude 390RK stretches 30.5 ft while the Forest River Sierra 391FLRB spans 38.0 ft. Weight-wise, the Forest River Sierra 391FLRB is the lighter rig at 9,300 lbs versus 15,400 lbs.

Capacity-wise, expect to sleep 10 in the Grand Design Solitude 390RK versus 6 in the Forest River Sierra 391FLRB. With 4 and 1 slide-outs respectively, the parked floor plans differ significantly.

Tank capacities are a key off-grid consideration. The Grand Design Solitude 390RK carries 70 gal of fresh water, 68 gal gray, and 41 gal black. The Forest River Sierra 391FLRB offers 75 gal fresh, 41 gal gray, and 49 gal black. The Forest River Sierra 391FLRB has the edge for extended dry camping.

Budget-wise, the Forest River Sierra 391FLRB is listed at $60,000 compared to $62,000 for the Grand Design Solitude 390RK.

For family camping trips, the larger floor plan and additional berths make a real difference. For boondocking, the model with superior solar and battery setup will keep you comfortable off the grid longer. If you're going full-time, the larger tanks and more robust build quality matter enormously.

Both options have earned their place in the market. Your trip style and budget should be the final tiebreakers.