This Spartan-based diesel pusher has undergone a redesign for the 2016 model year.
By Mark Quasius, F333630
December 2015
After experiencing rapid growth, Entegra Coach has positioned itself as a major player in the Type A motorhome market. The company’s flagship model is the Cornerstone. It exhibits everything one would expect in a luxury motorhome, and more.
Recently Entegra announced a major redesign of its entire 2016 lineup, which includes the Aspire and Anthem, as well as the Cornerstone. The most visible changes are new front and rear caps that feature modern styling, and LED-backlit stainless-steel trim.
The Cornerstone is available in four 45-foot floor plans for 2016, including the all-new 2016 45A, which is the focus of this article.
Construction
Entegra’s builders have chosen the hung sidewall method over the vacuum-laminated construction typically used in RV manufacturing. This allows for strong, durable sidewalls filled with acoustical-grade fiberglass insulation batts and reflective waffle-weave foil, a combination that creates excellent insulation and sound deadening. The 2 1/2-inch-thick interior walls are lined with 1/2-inch plywood.
Instead of laying oriented strand board (OSB) on top of the steel floor subframe, a wooden floor made of 3/4-inch plywood is built on top of the steel framework. It is insulated to a value of R-33, practically unheard of in the RV industry. This design also deadens vibrations and road noise and contributes to a smooth, quiet ride.
Entegra modifies the Spartan K3 chassis by adding X bracing in the basement areas. This creates a more rigid box to mount the coach on, allows the suspension to do the work, and minimizes frame twisting. For even more rigidity, horizontal X bracing is placed beneath the basement floor. A steel hoop, similar to a roll bar, is placed over the cockpit area to further increase strength and eliminate any flex in the cockpit or front cap areas. These techniques contribute to an excellent-handling coach that has minimal lean or body twist when turning corners.
Chassis
The Spartan K3 is used by a number of high-end coach builders and, especially with Entegra’s upgrades, makes a great foundation for the Cornerstone. The coach has a 54,000-pound gross vehicle weight rating (GVWR), with a gross combination weight rating (GCWR) of 74,000 pounds. A hitch rated at 20,000 pounds is included.
Power is provided by a 15-liter Cummins ISX engine that puts out 600 horsepower at 1,800 rpm and 1,950 pound-feet of torque at 1,200 rpm. The power plant is equipped with a three-speed engine compression brake and automatic traction control. An Allison 4000 MH series six-speed automatic transmission delivers the power to the rear drive axle. All six wheel positions use disc brakes equipped with a Wabco antilock brake system.
The independent front suspension features a 55-degree wheel cut and upgraded 60-mm Bilstein shocks. A Hadley SLS air leveling system automatically adjusts during the ride and can be used to level the coach when parked. Equalizer Systems’ dual-acting jacks use hydraulics to raise and lower the jacks when additional stability is desired, or if the ground pitch is too excessive for the air leveling to function. A 150-gallon fuel tank and 15-gallon DEF tank complete the chassis.
Exterior
The Cornerstone’s totally redesigned exterior has to be seen to be appreciated. The front cap features Xenon headlamps set into stainless-steel bezels, surrounded by LED accent lighting. The stainless-steel Entegra emblem bar across the front is backlit with soft LED accent lighting. The center LED upper clearance lights are also recessed in a stainless-steel bezel.
The rear cap has been redesigned in a similar manner. Red LED accent lighting surrounds the LED taillights in stainless-steel bezels. A rocker switch activates a new power lift that effortlessly raises the engine compartment access cover. The accent panel at the rear of the coach uses red LED backlighting to illuminate the Entegra emblem cut into the stainless-steel trim.
The review coach was graced with the Topaz full-body paint scheme, characterized by gold and bronze graphics in a dark base color.
Stainless-steel rocker panel coverings extend down both sides of the coach. Girard awnings with LED lighting are built into the upper fascia. The smooth, sleek appearance is further complemented by flush deep-tinted windows, chrome baggage compartment latches, chrome wheel well trim, and LED docking lights.
One key feature of any Entegra motorhome is the cab-forward design. The dash rolls off and down to meet the base of a huge windshield. This offers excellent visibility immediately in front of the coach, which is helpful when maneuvering in tight quarters. It also enables the mirrors to be positioned below the driver’s eyes. Doing so eliminates blind spots, because the driver can look over the mirrors rather than around them. It also produces a lower angle from which to view traffic behind you, as well as the coach’s rear tires.
The 39-inch wiper blades did an excellent job of keeping the entire windshield clear on a rainy 300-mile drive along an interstate highway.
The Cornerstone’s slideouts retract flush; tight seals make them nice and quiet, with no perceptible wind leaks or whistles when the coach is being driven or when parked. The entry door, also flush-mounted, is fitted with a pneumatic door latch system that grabs the door and pulls it tight whenever the parking brake is released. This allows the door to open and close easily without tugging or slamming, yet seals it tightly to eliminate wind noise during travel.
The exterior entertainment center includes a 40-inch LED TV and a JBL sound system. Girard window awnings and a power door awning provide plenty of protection against sun or rain.
Interior
The review coach featured the Mocha interior décor package, with natural glazed cherry woodwork. Three décor packages are offered, along with four wood choices. Entegra motorhomes feature Amish woodworking, and the quality is evident from the ceiling treatments down to the baseboards.
The polished porcelain floor boasts an inlaid mosaic tile centerpiece. All countertops are quartz and feature LED accent lighting beneath the leading edge. The Villa sofa bed is equipped with an air mattress and kick-out footrests. The 82-inch couch and the captain’s chairs are covered in real leather and accented with brass rivets.
Cockpit seating is comfortable, with heated, six-way leather chairs that have power footrests and pneumatic lumbar supports. The instruments are easy to read. A touch-screen Xite infotainment center features Rand McNally GPS software that is designed for RVs, along with Bluetooth capability and Sirius XM satellite radio. A USB jack will accept iPods or other devices as auxiliary audio inputs. The entertainment system can be controlled by paddle switches on the Smart Wheel.
The rear camera displays on a secondary monitor; whenever a turn signal is activated, it temporarily switches to a split screen to show both the rear camera picture and the appropriate side camera.
The 45A comes standard with an angled entertainment center behind the driver’s seat. It consists of a fireplace surrounded by a hardwood mantle and a 50-inch LED TV mounted in a fixed position on a quartz top. A small window is located to the left of the TV, where there is space for a recliner. Instead of this arrangement, our coach was equipped with the optional desk, which really opens up this area. The 50-inch LED TV rises out of the desk via a power lift. With the TV lowered, the 60-inch-wide window behind the desk affords an expansive view. The desk area includes a slide-out tray for a keyboard or laptop computer, a drawer for hanging files, and a standard desk drawer — even a fireplace. Two large compartments in this area house the satellite receiver or DVR, the Bose surround system, a Blu-ray player, and any other entertainment gear desired.
An additional 32-inch LED TV is located in the front overhead cabinet. A Winegard Rayzar Automatic antenna pulls in off-air broadcast signals with ease without needing to be raised or lowered. An optional Winegard Trav’ler automatic satellite dish also was included in this motorhome.
On the curbside, a 6-inch-wide shelf runs behind the couch and dinette. This allows the dinette table to pull out far enough to accommodate four adults for dining. Large windows behind the couch and dinette give occupants a nice view of the patio area.
A 22-cubic-foot double-door residential refrigerator with a lower freezer drawer stands immediately aft of the dinette, followed by a large pantry that has one large pull-out on the bottom and a normal drawer above it. The top half has dual slide-out pantries that are handy for storing large bottles, among other food items.
The 97-inch-wide galley, located on the driver’s side, opposite the dinette, is Entegra’s largest. It holds an induction cooktop and a stainless-steel sink. The sink covers are fitted with nylon cutting-board material on one side. They can be stowed in a padded storage rack beneath the sink. The silverware drawer is double-decked, with drawer slides on the top tray. A large pull-out work area extends from the counter. Overhead is a convection-microwave oven, as well as the usual cabinetry. Below is a Fisher-Paykel dishwasher drawer alongside a large pull-out compartment for a wastebasket.
The midcoach bath contains an electronic-flush macerator toilet, a vanity, and a sink. A spacious mirrored medicine cabinet has a side wing that contains the thermostat and controls for the Aqua-Hot hydronic heating system and the SeeLevel tank monitoring system. A 12-volt fuse panel that interfaces with the Firefly Systems multiplex wiring controls is also located there.
The bedroom can be separated from the living area by a sliding door. Its king-size bed rises to expose additional storage space. New for 2016 is a Tempur-Pedic Cloud mattress — the first time it is being used in the RV industry. We found the mattress to be super comfortable. A decorative ceiling treatment is fitted with mirrored panels, LED lighting, and a ceiling fan. Controls for the fan and multiplex lighting, located in the overhead cabinet, are accessible from the bed.
Opposite the bed, in the curbside slideout, are a quartz-topped dresser and plenty of storage drawers. Overhead cabinetry includes a 32-inch LED TV that can be used with the front entertainment center equipment; the cabinet swings open to expose a second Blu-ray player and room for a second satellite receiver or DVR if desired. A bedroom safe is located in this area.
A second sliding door separates the bedroom from the rear bath — a new design in the 45A that incorporates a large shower and vanity. The 46-inch-by-36-inch shower is roomy enough for even the largest person. It’s finished in porcelain tile with a ceramic stone floor and surrounded on two sides by a custom glass enclosure. The vanity is 46 inches wide and has a single-basin sink with plentiful counter space. The medicine cabinet offers lots of storage room.
In most diesel pushers, the floor rises to create clearance for the rear engine. In the 45A, the floor near the vanity remains level, and maximum height is created in the shower. Just beyond this point is a 5-inch step that leads to a Tecma macerator toilet, as well as a stackable washer and dryer. A cedar-lined wardrobe runs the full width of the motorhome.
Utilities
The Cornerstone’s utilities are first-class. A 12,500-watt Onan diesel generator is mounted on a pneumatic slide rail for easy access. A 50-amp cord connects to campground power, while two Magnum true sine wave inverters (2,800 watts and 2,000 watts) handle most AC power needs when the generator does not need to be run. An Aqua-Hot 450D hydronic heating system handles domestic hot water needs and heats the coach interior and basement zones. It also warms the tile floors in cool weather.
Two power cargo trays slide out on either side of the coach to provide access to stowed items. An optional 2.8-cubic-foot basement freezer was located in the front-most curbside bay, mounted on a slide-out tray.
The utility bay is another new design for 2016. The holding tanks are equipped with electric dump valves that feed to Thetford’s new Sani-Con Turbo macerator, which dumps much faster than the previous model and drains the tanks in about the same time as a standard 3-inch slinky dump. The power hose reel, water filters, paper towel dispenser, and other typical controls and accessories also are found there.
Cooling needs are met by three 15,000-Btu ducted air conditioners, which provide quiet airflow throughout the coach. These units are equipped with heat pumps that allow the overhead ducts to warm the coach when needed. If the temperatures don’t become too unreasonably cold, the heat pumps and the fireplace can keep occupants warm and comfortable without use of the Aqua-Hot system.
Driving Impressions
Company literature describes Entegra’s motorhomes as “the quietest riding, best handling” coaches on the market today. That’s a pretty tall claim, so I was eager to find out. After a few thousand miles behind the wheel of the 45A, I concluded that wind noise was minimal; road noise was absorbed by the wooden floor rather than transmitted to the interior; and handling was crisp as the suspension did its work. The coach exhibited minimal lean in corners. Steering was nice and tight, enabling me to drive easily with one hand as a test.
Naturally, the 600-horsepower engine is immediately noticeable. On steeper grades, the 1,950 pound-feet of torque allowed me to hold my speed. I appreciated the power when entering the highway via an on-ramp, or when exiting a rest area. With traffic bearing down in both lanes, the big Cummins accelerated right up to speed, and I safely merged with traffic. When cruising, the 15-liter ISX engine loped along at a low rpm without breaking a sweat. I actually found a slight fuel economy increase with the 15-liter ISX over a previous 9-liter ISL engine, as the ISX worked at less load and a lower rpm.
When stopping, the coach complied quickly, almost as though an anchor were thrown out. The three-speed engine compression brake worked well with the larger displacement of the 15-liter ISX. The six-wheel disc brakes performed well, even in stop-and-go traffic. The brakes, as well as the engine compression brake, enabled an effortless descent down the 10 percent grade of the Teton Pass in the Bighorn Mountains en route to Jackson Hole, Wyoming.
With its handling, ride, brakes, and power, the Cornerstone seemed like the biggest sports car I’d ever driven. Add in the interior comfort level, a beautiful interior and exterior, quality workmanship, and numerous features, and I can see why the Cornerstone is a popular choice among RV buyers.
SPECS
MANUFACTURER
Entegra Coach, P.O. Box 460, Middlebury, IN 46540; (800) 517-9137; www.entegracoach.com
MODEL
2016 Cornerstone
FLOOR PLAN
45A
CHASSIS
Spartan K3; raised rail, side radiator
ENGINE
Cummins ISX 15-liter; 600 horsepower at 1,800 rpm; 1,950 pound-feet torque at 1,200 rpm
TRANSMISSION
Allison 4000 MH 6-speed
AXLE RATIO
4.30 to 1
TIRES
front axle — Michelin XZA 365/70R 22.5 LRL;
drive and tag axles — Michelin XZA 315/80R 22.5 LRL
WHEELBASE
320 inches
BRAKES
six-wheel antilock disc air
SUSPENSION
Reyco Granning independent front air suspension; Ridewell tag axle suspension
ALTERNATOR
210 amps
BATTERIES
chassis — (2) 950 cca
house — (8) AGM
INVERTER
(1) 2,800-watt true sine wave; (1) 2,000-watt true sine wave
ELECTRICAL SERVICE
50 amps
AUXILIARY GENERATOR
Onan 12,500-watt; automatic generator start
EXTERIOR LENGTH
44 feet 11 inches
EXTERIOR WIDTH
101 inches
EXTERIOR HEIGHT
12 feet 9 inches
INTERIOR HEIGHT
7 feet
GROSS COMBINATION WEIGHT RATING (GCWR)
74,000 pounds
GROSS VEHICLE WEIGHT RATING (GVWR)
54,000 pounds
GROSS AXLE WEIGHT RATING (GAWR)
front — 20,000 pounds;
rear — 20,000 pounds;
tag — 14,000 pounds
AS-TESTED WEIGHT
(weighed with cargo, full fuel and water)
front axle — 18,180 pounds;
rear axle — 19,440 pounds;
tag axle — 12,020 pounds;
total — 49,640 pounds
FRESH WATER CAPACITY
100 gallons
HOLDING TANK CAPACITIES
black water — 42 gallons;
gray water — 63 gallons
FUEL CAPACITY
150 gallons plus 15 gallons DEF
FUEL REQUIREMENTS
diesel
WATER HEATER
Aqua-Hot 450D hydronic heating
HEATING SYSTEM
Aqua-Hot 450D hydronic heating
AIR-CONDITIONING
(3) 15,000-Btu, ducted, with heat pumps
REFRIGERATOR
Samsung 22-cubic-f00t residential
TOILET
(1) Tecma porcelain with macerator; (1) porcelain electric flush
WARRANTY
coach — 2 years/24,000 miles bumper to bumper;
chassis — 3 years/50,000 miles;
structure — 5 years
BASE SUGGESTED RETAIL PRICE
$624,715
PRICE AS TESTED
$630,977