Dynamax’s 2020 DX3 Super C is a hit on the road and at the RV resort

Size and power are the hallmarks of a big rig, right? Who hasn’t dreamed of taking a semi out for a spin? Being up that high, in control of all that power and size … even just once. For most enthusiasts, the closest they will come to a big rig is piloting a Class A motorhome, which still has a personality that promotes the feeling of being in something much bigger than a car.

Nevertheless, an ever-increasing segment of the motorhome industry showcases coaches that are a combination of semi-truck and RV. Affectionately called the “Super C” motorhome, we decided to see just how far the segment has come since we previewed the Dynamax Isata 230 back in 1998.

Interior living space of Dynamax’s 2020 DX3 Super C motorhome
The galley and living area have more than ample prep and serving space for a big party. The test vehicle included the optional fireplace and pop-up TV in place of the standard Comfort Lounge. Photos: Shawn Spence

The all-new 2020 Dynamax DX3 37TS is built on a customized Freightliner Business Class M2-106 chassis. At a touch over 39 feet in length, the DX3 isn’t appreciably larger than many diesel-powered Class A’s. Yet its appearance, luxury appointments and drivability make it stand far apart from the rest of the pack.

Exterior of Dynamax’s 2020 DX3 Super C motorhomeWhat’s Hot

Paint, drivability, ride, cab layout, furnishings, kitchen layout, counterspace and appliances

What’s Not

Kitchen faucet gets hit by cabinet door, no roof access ladder

A division of Forest River, Dynamax started out building luxury Super C motorhomes, but over the years has branched out to include smaller offerings as well as four-wheel-drive models built on heavy-duty pickup chassis. The DX3 is the company’s patriarch, and once you step inside and get behind the wheel, you’ll be hard pressed to resist signing on the dotted line.

The Inside Scoop

Dynamax works hard at maintaining its luxury badge, and according to the company’s general manager, Brian Clemmons, its team is in regular contact with many long-time and repeat owners, which keeps the designers and planners current. Clemmons, who travels frequently in a Dynamax with his family and friends, carefully analyzes his (and their) experiences and brings back valuable input to the design team. This attention to detail is clearly evident after testing the DX3.

Interior living area of Dynamax’s 2020 DX3 Super C motorhome
Viewing the TV and electric fireplace is easy from the optional theater seating.

The 37TS floorplan is somewhat of a rarity in the luxury Super C space, in that the company offers an optional ($1,942), and quite large, cabover bed in lieu of a smaller cap with cabinets. This result is a kid’s dream. The 81-by-58-inch bed features a large HDTV on a swing-away bracket to be enjoyed while hanging out in the bunk, or that can be positioned as an additional TV for those in the living room. Add the sleeping accommodations up top with the convertible 42-by-60-inch dinette and the rear king bed and six can sleep comfortably; eight wouldn’t be impossible, but they would need to really “like” each other.

The test coach has the Brindle interior treatment, one of three available, along with two cabinet color choices. The names of the cabinets, Driftwood and Caramel, are somewhat of a misnomer in that the caramel is more of a mahogany and the Driftwood is more of an oak. That said, the interior with the Caramel cabinetry had a stately, high-end look and feel, which we appreciated.
DYNAMAX-2020-DX3-SUPER-C floorplanThe front lounge is almost level with the floor in the cab in this model, which means the front seats are able to rotate for additional seating and socializing. Opposing slides open up the lounge and galley nicely. All the furniture, including two optional reclining theater seats ($742), is overstuffed and comfortable. The theater seats face a very interesting and deep optional cabinet ($1,042), which has ample storage, an electric fireplace and a 50-inch 4K HDTV that rises from the back portion of the cabinet. The cabinet is topped off with a 36-by-62-inch solid-surface counter, which is ideal for displaying a variety of snacks and refreshments while entertaining guests.

Just inside the entry door, directly behind the cab, is a freestanding cabinet, which serves as a coat closet and offers access to some of the coach controls. A Precision Circuits multiplex wiring system controls lighting, slideouts, HVAC, auto generator start, the level monitor and the power-management system. A smart device app for the Precision Plex system is available, which allows function access on the go from a phone or tablet. Not all of the coach systems are controlled through Precision Plex center, however; the awning systems are controlled via Carefree of Colorado’s intuitive app, and the Equalizer leveling system works using the company’s EQ app. After testing all three apps on an iPhone 7+, it was clear why Dynamax opted to leave the awning and levelers out of the multiplexing system; the Carefree and EQ apps are feature-rich, and controlling them doesn’t require flipping though multiple menus and screens to operate the leveling jacks or awning. Lighting can be controlled from the main screen, app or via lighted touchpads throughout the coach.

Interior master suite of Dynamax’s 2020 DX3 Super C motorhome
the king size bed fits nicely in this master suite.

Directly across the motorhome, behind the driver’s seat, is another cabinet, which contains the Equalizer leveling system control panel, manual slide-room controls, the cabover TV arm control and the Aqua-Hot hydronic heating system switches. All are illuminated by a concealed LED light strip inside the cabinet, which is a nice touch. Outside of the cabinet are the front HVAC thermostat, Magnum inverter/charger controls and the Go Power solar-system charge controller.

The galley is a foodie’s paradise, plain and simple. Cabinet storage is ample, featuring many deep compartments. Counterspace is off the charts. The passenger side front slide is fitted with a solid-surface countertop from front to back that adds up to 38½ square feet of counterspace, if you include the aforementioned TV/fireplace cabinet, the fold-up countertop extension and the right-side galley sideboard.

The double-bowl stainless-steel sink has flush-cut solid-surface covers, which add to prep space. It’s also equipped with a gourmet pre-rinse, high-arc, pull-down kitchen faucet. This is a great component, although the upper cabinet door hits the faucet, which likely will become damaged in a short amount of time if owners are not careful. The door opens about a third of the way before making contact with the faucet, so if you can live with that, it’s best to install a tie-back inside the door to keep it from hitting the faucet.

Interior vanity space of Dynamax’s 2020 DX3 Super C motorhome
The walk-through vanity with pocket doors offers ample storage space.
Interior (shower) of Dynamax’s 2020 DX3 Super C motorhome
The side aisle water closet and shower room features enough space to get the job done, although this 6-footer found the shower a bit claustrophobic (but still workable), despite its high-end appeal.

Higher-end appliances would naturally be expected in a luxury motorhome, and the DX3 does not disappoint. A dual-burner True Induction cooktop sits directly below a Sharp Carousel over-the-range convection microwave. A Frigidaire 16.3-cubic-foot residential refrigerator and a pantry are situated across the motorhome from the cooktop.

The split walk-through bathroom has an open sink and vanity with the toilet and shower in a side-aisle room. The shower is somewhat on the tight side, which is not what we’d expect in a coach of this class and size, but gets the job done stylishly. A ceramic toilet is mounted above the floor on a step box.

The master bedroom has a king bed in a slideout with a bit of hidden storage underneath. The closets and cabinets on the opposite side are cedar-lined, and offer an abundance of storage space. The TV conceals a hidden storage cubby, and there’s plenty of floor space for daily primping.

More importantly, most of the coach is accessible with the slides closed, including the bathroom. Crawling into bed with the slides closed is also possible for that overnight stopover at the Flying J.

Behind the Wheel

The driving experience is what allows the Super C to truly stand out. Not all Super C’s are created alike, and although there are custom rigs built on Volvo, Kenworth and other tractor chassis, the Freightliner M2 chassis is the chassis of choice in this space.

The benefits of a conventional Class C are twofold. Getting in and out the side doors from the front seats is a big selling point, and service access (in most cases) without the need to intrude upon the inside the living space is high on the list of features. While Super C’s also have these features, there is a bit of a climb into and out of the cab, which has a commercial-truck feel. Two added benefits are superior vision of the road, and that the engine and front wheels are out in front of the driver. This restores the feeling of driving a conventional vehicle instead of one where you’re sitting above the wheels, as is the case while piloting a Class A. While servicing is easier, and visualizing what’s around you more clearly is a strong point, the noise level is noticeably higher inside the cab when compared to that inside a diesel pusher. But it’s easy to dig those custom plush air-ride driver’s and passenger seats.

Cab area of Dynamax’s 2020 DX3 Super C motorhome
The Freightliner cab, designed for long-haul truckers, is convenient and super comfortable.
Engine of Dynamax’s 2020 DX3 Super C motorhome
Tilting the hood reveals the Cummins 350-hp ISL-9 engine, where most things are easy to access.

Power provided by the ISL-9 Cummins diesel moves this coach along very nicely. It’s responsive on acceleration, and is equipped with commercial-truck Jacobs dual-stage C-brake (engine compression release) with high, low and off settings, instead of an exhaust brake. It’s mated to an Allison 3200 six-speed transmission with push-button controls that’s rated at 350 hp with 1,000 lb-ft of torque. Everything on this chassis reflects its commercial heritage, including the 275-amp alternator, Bilstein shocks and a 20,000-pound-rated hitch receiver. Oh, and did we mention that the realistic occupant cargo carrying capacity (ROCCC) is 6,574 pounds?

The steering is tight on the M2 chassis, and the air suspension, upgraded shocks, heavier sway bars with clevis-type bushings and aforementioned air ride seats add up to a very comfortable, stable ride. All the controls, as expected, are well within easy reach and visibility of the driver. While the smart-wheel technology of the Freightliner Class A chassis hasn’t quite reached the M2 yet, the chances are good that this feature will be available in the future.

Safety is another place where the DX3 excels. The Freightliner M2 has a 5-foot front crumple zone, which will no doubt make a difference in the event of a frontal collision. Those frontal collisions can be avoided thanks to the optional Mobileye Collision Avoidance System ($1,369). The optional Truck System Technologies (TST) tire-pressure monitoring system ($442) is installed on the dash.

Lastly, the optional upgraded Kenwood/Garmin RV in-dash navigation and stereo system with SiriusXM satellite radio ($1,042), along with JBL premium in-cab sound ($940), make driving even more enjoyable.

The Outside Story

When at the top of the game, a motorhome should look like art. Not that the full-body paint options on other motorhomes aren’t nice. But here we’re looking at art. Indiana-based Dean Loucks Custom Design & Paint + Fine Art is known for transforming the exteriors of coaches into art. Companies like Millennium Coach and Liberty Coach use Loucks’ paint jobs on their Prevost conversions, and Dynamax employs Loucks for the DX3.

The paint on this coach, which is signed by Loucks, is something to behold. It appears three-dimensional, like you could sink your hand into it, feel the elements of the paint, and even slide your hand behind them. Loucks’ paint jobs garner a lot of attention. Combine his paint with the DX3 with its Alcoa aluminum wheels with chrome hub covers and lug caps, and you can charge admission. All door handles and hardware are black, which accents the paint nicely, and other chrome accents are tastefully appointed.

Thetford’s Sani-Con Turbo macerator system
The DX3 features Thetford’s Sani-Con Turbo macerator system, hose reel and water filter.

Basement storage features side-opening baggage doors, and while they aren’t as large as on some Class A’s, there’s still plenty of space. An outside entertainment center with HDTV and Jensen stereo is the center of attention when tailgating or watching the NASCAR race. A couple of the compartments are high-top pass-through, so with a little planning, a lot can be stored in the basement.

The Final Word

Dynamax RV

The Super C motorhome has come a long way since its beginnings. This coach is well-equipped and appointed appropriately for luxury status. The chassis has certainly improved over time, and this nicely tuned and customized Freightliner M2 rides smoothly with excellent handling manners. Even if you don’t need to carry more than 3 tons of cargo or tow 20,000 pounds, the Dynamax DX3 is a great home on the road. And, you can live the dream of driving a big rig every day.



Model Freightliner M2-106
SAE Hp 350 @ 2,000 rpm
Torque 1,000 lb-ft @ 1,400 rpm
Transmission 6-speed automatic
Axle Ratio 4.56:1
Tires 275/80R22.5
Wheelbase 268″
Brakes Front/Rear Air with four-wheel ABS
Suspension Front/Rear Leaf spring/air
Fuel Capacity 100 gal
Fuel Economy 9 mpg (est)
Warranty 2 years/unlimited miles;
Engine 5 years/100,000 miles;
Transmission 5 years/unlimited miles

System controls of Dynamax’s 2020 DX3 Super C motorhome
System controls are conveniently located behind the cab.


Exterior Length 39′ 2″
Exterior Width 8′ 5″
Exterior Height with A/C 12′ 9″
Interior Width 8′ 1″
Interior Height 6′ 11″
Construction 2-inch aluminum frame, laminated side walls with block-foam insulation. Crowned, aluminum-frame roof with one-piece fiberglass
Freshwater Capacity 94 gal
Black-water Capacity 52 gal
Gray-water Capacity 52 gal
Water-heater Capacity On-demand
Propane Capacity N/A
Air Conditioner (2) @ 15,000 Btu ea
Furnace Hydronic
Refrigerator 16.3-cu-ft
Inverter/Charger 2,000 watt /125 amps
Batteries (2) 12-volt chassis,
(2) 12-volt AGM house
AC Generator 8.0 kW Diesel
MSRP $324,147
MSRP, as Tested $339,236
Warranty 2 years

Wet Weight

(Water and water heater, fuel, propane tanks full; no supplies or passengers)
Total 26,426 lbs

Chassis Ratings

GAWR, F/R 12,000 lbs/21,000 lbs
GVWR/GCWR 33,000 lbs/54,000 lbs
ROCCC 6,574 lbs
GAWR Gross Axle Weight Rating
GVWR Gross Vehicle Weight Rating
GCWR Gross Combination Weight Rating
ROCCC Realistic Occupant and Cargo Carrying Capacity (full water, no passengers



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