The Class C motorhome has always been the poor cousin to the “A”. It was designed to carry as much motorhome as a chassis could stand – on a platform that frankly was designed for box vans carrying cargo – not people. This typical Class C was invariably gas-powered and (if I flip my viewpoint) was as much motorhome as someone who couldn’t afford a gasoline run Class A (let alone a diesel) could expect. Champagne tastes; beer budget – something like that.
But, there is a new option emerging – one that not only offers a better chassis for the Class C but also the benefits of a diesel engine; the GM C-series. Re-introduced in 2003 these medium-duty trucks are a trucking mainstay; carrying everything from your daily newspaper to the cola you drink, but GM (right from the start) recognized the potential in the recreational market. First offered as a fifth-wheel hauler (I hauled a triple-axle 40-foot Gulf Stream Prairie Schooner from Indiana to Florida with one in ’04) and now as a solid platform for the motorhome builder.
The C4500 has gross vehicle weight ratings (GVWR) of 16,500 and 17,500 pounds, while the C5500 will handle 18,000-19,500-pounds. Both of which are spot-on to handle many of the new fifth wheels that are being built; but for the Class C market the C5500 can offer 22,000 lb of carrying capacity and that is what attracted my attention to the Jayco Seneca.
Despite its size the inside layout of the C-series is pickup-like – with a regular size steering wheel and the usual power-assists. Also with the sloping hood, drop-away fenders and large glass area you get excellent visibility and you’re not overwhelmed with the truck’s size. In addition the C-series has a 53-degree wheel cut that allows a turning diameter as low as 47 feet while the sharply sloped hood gives the driver the ability to see objects on the ground as close as 13 feet in front of the truck (as measured from the front bumper).
For power the C-series engine of choice is the new 6.6 L Duramax diesel engine coupled to the six-speed Allison automatic transmission. With the engine entirely outside the motorhome – routine maintenance as well as diesel service is easy as the forward tilting hood lets the owner (or mechanic) stand in the wheel well and have full access to every part of the engine.
When I walked into the Seneca I was struck by the upscale look of the unit; which reminds me – despite what I’m saying about getting into a diesel powered motorhome with this chassis we are still talking about a unit worth nearly $150,000. Still, first impressions count and with the opposing slideouts open this 35-foot unit up into a very large comfortable salon and kitchen space.
Overhead cabinets and kitchen cupboards have solid maple hardwood doors, some accented with cut glass, while the wood is also used on the two-door refrigerator front and the slideout frames. In the one slide the semi-L shaped kitchen creates extra counter space while the sink is also offset with a tall gooseneck faucet that swings out of the way for washing up. A window right by the sink lights up the counter.
For appliances you have an overhead built-in microwave and an oven just below the three-burner range. The countertop is a solid surface material called J-Stone. Floor coverings are a combination of vinyl and carpet with a good separation – keeping the carpet away from areas that can get wet or suffer food spills.
The focal point of the unit is the large flat-screen TV (and other entertainment components) in the cab-over space at the front of the motorhome. This wall to wall setup can be seen from anywhere in the rig and it also offers additional storage space in the handsome cabinetry. Still, it doesn’t take up the whole space. Just below the cabinet is a slideout drawer that is actually a full-length single bed. When not in use the bed pushes forward under the unit and creates a much more accessible hatch to the driver and passenger seats in the front of the truck.
While I can see this unit as a nice setup for two it does have the potential to sleep up to seven with the dinette down, the leather couch folded out, the overhead slideout single in use and the rear queen bed occupied.
The rear bedroom in my test unit also had a slideout, so three in total; this expanded the space in the master makes it easy to access and use the full-wall wardrobe and adjoining bathroom. And with a second TV back there and a door it’s a nice get-away space. In this floorplan the toilet is separate with a hard door of its own while facing it is the corner glass shower, sink and vanity. Placed between the salon and bedroom it can be used by owners or guests – privately.
The separating wall between the bath and kitchen is home to Jayco’s “Command Center” which houses all the switches for the slideouts, generator, pumps and other readouts. There is also a spot for hanging keys and it’s all safely behind a glass door. Only the thermostat is outside – just next to it.
The other benefit of using a chassis such as the C5500 provides is the chance to box-in the frame and create Class A- style basement storage. Large, lockable, flip-up cargo doors open up to pass-thru storage as well as an outside utility and dump center complete with light and shower. This means that the tanks are also embraced by the heated space making this Class C impervious to the cold.
Further along is housed an Onan 6000-watt diesel generator that draws fuel from the Seneca’s standard 80 gal fuel tank. That equals a lot of time out in the boondocks if you so choose; in fact you’d likely run out of water before diesel.
The Seneca uses vacuum-bonded laminated sidewalls with a smooth gel-coat finish that is both tough and easy to clean. Sandwiched into the sidewalls and roof is foam insulation that gives the Seneca R-ratings of 25 in the roof and 9 in the walls and floor; though the windows are single-pane glass. For rain and sun protection each Seneca comes with a standard 18-foot Carefree 12V electric awning. The control for this convenience is just inside the side-door – easily reached while standing outside. Also just beside this switch is the master battery shut-off; well placed.
Driving the Seneca is easy (if you don’t forget about the tail swing) and with this heavy-duty steel frame under you this unit, even at 35-feet long, is much less susceptible to the sway and the rocking-horse action that plagues many Class C’s. The added height of this unit also makes for better visibility and a feeling of further confidence. All this despite the fact that the cab interior is little larger than a pickup truck dash setup. But, the best thing about this unit is the engine. At 650 foot-pounds it offers ample torque for any acceleration task or hill climbing duty – not to mention the benefits of the standard engine exhaust brake and the holding power of the Allison transmission. Only the most severe grades will ever require you to actually brake. Again, this feeling of confidence is enhanced by the back-up camera and monitor and the large heated mirrors that are mounted to the A-pillar of the truck – not the doors – much less vibration. And then there is the straight up benefit of the improved mileage you can expect from the 6.6L Duramax…but I think you get my point.