If you’re shopping for a premium Super C diesel motorhome with serious capability and luxury amenities, the Grand Design Lineage Series F 31ZW vs Dynamax Isata 6 31KS are two of the strongest contenders. Both models are built on the rugged Ford F-600 4×4 chassis, delivering impressive towing power, diesel performance, and boondocking readiness in a manageable ~34-foot package.
This in-depth comparison covers chassis specs, dimensions, capacities, interior features, suspension, off-grid capabilities, pricing, and key differences to help you decide which Super C best fits your travel style.
Identical Powertrain and Chassis Foundation
Both RVs share the same robust foundation, making them direct competitors in the growing F-600 Super C segment:
- Chassis: Ford F-600 XLT Cab Chassis 4×4
- Engine: 6.7L Power Stroke V8 Turbo Diesel
- Horsepower / Torque: 330 HP / 950 lb-ft
- Transmission: TorqShift 10-speed automatic
- GVWR: 22,000 lbs
- GCWR: 43,500 lbs
- Towing Capacity: 15,000 lbs
- Fuel Capacity: 66–66.5 gallons
- Wheelbase: 245″ (Grand Design) / 244″ (Dynamax)
This chassis combination provides excellent stability, highway manners, and moderate off-road performance for a diesel Super C.
Dimensions and Weight CapacitiesHere’s a side-by-side look at the verified exterior and tank specifications:
Feature | Grand Design Lineage F 31ZW | Dynamax Isata 6 31KS |
|---|---|---|
Overall Length | 33′ 9″ | 34′ 1″ |
Exterior Width | 8′ 4″ (102″) | 8′ 5″ (101″) |
Exterior Height | 12′ 3″ | 11′ 11″ (with A/C) |
Interior Height | 81″ (6′ 9″) | 84″ (7′ 0″) |
Fresh Water | 79 gallons | 78 gallons |
Gray Water | 66 gallons | 45 gallons |
Black Water | 45 gallons | 45 gallons |
LP Gas Capacity | 20.3 gallons (86 lbs) | 20.3 gallons (86 lbs) |
Sleeps | 5 | 5 |
Slides | 2 | 2 |
The Lineage 31ZW offers a slight edge in gray water capacity and a more compact length, while the Isata 6 31KS provides taller interior headroom.
Suspension and Ride Quality
- Grand Design Lineage F 31ZW: Features a custom MORryde-modified chassis with Fox Racing adjustable suspension (including remote reservoir shocks). This highly tunable system allows owners to dial in the ride for highway comfort or off-road performance. Many reviewers praise its adaptability and sporty feel.
- Dynamax Isata 6 31KS: Equipped with MORryde RSX suspension and Bilstein shocks. It delivers a solid, stable ride but is less adjustable than the Fox system.
Advantage: Grand Design for drivers who want customizable handling.
Interior Layout and Key Features
Both models use a similar double-slide floorplan with a cab-over bunk, mid-coach living/kitchen area, full bath, and rear bedroom that sleeps up to 5.
Grand Design Lineage F 31ZW highlights:
- King bed (in slide)
- Power theater seating
- 10 cu. ft. 12V refrigerator
- Truma tankless water heater
- 900W solar (standard)
- 40″ exterior 12V smart TV
- Commercial-grade vinyl flooring and porcelain toilet
Dynamax Isata 6 31KS highlights:
- Queen bed (standard)
- Dual power reclining theater seats (standard)
- Larger 15 cu. ft. 12V refrigerator
- Induction cooktop and convection microwave with air fryer features
- Solid surface countertops and premium solid wood cabinetry
- Designer shower with skylight
Buyers often note the Isata for its more residential kitchen feel and higher-quality cabinetry, while the Lineage stands out for the king bed and modern, rugged aesthetics.
Off-Grid and Power Systems
- Both: 8 kW Onan diesel generator, 50-amp service, hydraulic leveling jacks, and strong lithium battery options.
- Grand Design: 900W solar standard (often with flexible panels) plus off-grid packages.
- Dynamax: Popular Xplorer Package adds up to 1,000W solar, four lithium house batteries (648 Ah total), insulated utility bay, and secondary tank heaters.
Both excel for extended boondocking, but the Dynamax Xplorer package is frequently praised as a turnkey off-grid solution.
Pricing (2026 MSRP)
- Grand Design Lineage F 31ZW: Starts at approximately $316,474 (base; actual dealer pricing and optioned units vary).
- Dynamax Isata 6 31KS: Series starts at approximately $298,299 (base; Xplorer-equipped units often land in the $310,000–$325,000+ range after options).
Real-world transaction prices are typically lower after dealer discounts, freight, and prep fees. Always get current quotes from authorized dealers.
Pros and Cons Summary
Grand Design Lineage Series F 31ZW
Pros: Adjustable Fox suspension, higher gray tank capacity, king bed, strong solar setup, aggressive modern styling, slightly shorter length for easier maneuverability.
Cons: Smaller standard refrigerator, newer model with less long-term owner feedback in this exact configuration.
Dynamax Isata 6 31KS
Pros: Larger refrigerator, premium cabinetry and residential kitchen appliances, proven Dynamax build quality, excellent Xplorer off-grid package, taller interior.
Cons: Lower gray water capacity, less adjustable suspension compared to Fox system.
Which Super C Should You Choose?
- Choose the Grand Design Lineage F 31ZW if you prioritize suspension tunability, maximum gray water capacity, a king bed, and a bold, adventure-ready appearance.
- Choose the Dynamax Isata 6 31KS if you value a larger refrigerator, upscale cabinetry, induction cooking, and a comprehensive off-grid package.
Both are high-quality, capable diesel Super C motorhomes on the Ford F-600 4×4 chassis. The best way to decide is to test drive them back-to-back and walk through actual units at a dealership. Pay close attention to ride quality, interior layout feel, and how specific options align with your boondocking or towing needs.
Ready to explore these models further? Visit your local Grand Design or Dynamax dealer, or check the official websites for the latest brochures and inventory.
