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2013 Entegra Cornerstone 45K

An In-Depth Review of Entegra Coach's Flagship Motorhome
Article Date: June, 2012


Entegra Coach is seen as one of the fairly new players in the Class-A market. But, in a way it has been around for quite a while.

Jayco's owners, Wilbur and Derald Bontrager, formed Entegra Coach when they resurrected the remains of the former Travel Supreme Motorhome Company. Entegra Coach then improved upon an already well accepted product and backed it with a commitment to service and quality not yet seen in competitive products.

Entegra is growing substantially as potential motorhome buyers recognize its value and is now one of the major players in the higher-end, diesel-pusher Class-A market. Entegra's flagship model is the Cornerstone, and I was invited to do a review and road test on this outstanding motorhome.

Construction Overview

The Entegra Cornerstone is available in a number of floor plans, all of which are 45 feet in length and are built upon Spartan's amazing K3 chassis. The Spartan K3 is the big boy of chassis used by many high-end, diesel-pusher manufacturers but Entegra takes it a bit further and adds some additional tweaks to provide an even more stable, smoother, and quieter ride. Rough or uneven roads typically twist the frame and motorhome superstructure causing those squeaks and rattles that accumulate over time. Entegra adds both vertical and horizontal X bracing to the chassis frame rails to stiffen the frame so that the suspension will handle the bumps rather than allowing the frame or superstructure to twist.

Vertical cross bracing adds additional rigidity to the chassis frame, allowing the suspension to perform better.

Further improvements are made by installing a steel hoop, similar to a roll bar, at the front of the coach to minimize any flex in the windshield area and provide an additional level of safety in the cockpit area.

Click Here for a link to the 2013 Cornerstone chassis spec sheet.


The Cornerstone features two methods of leveling the coach. A Hadley air leveling system will adjust the air-ride suspension bags to keep the coach level when parked. That's a plus when parked on blacktop parking lots or in soft soil conditions where jacks could sink in or cause damage to the surface.

That big 15 liter Cummins ISX in the Cornerstone's engine compartment is easy to access. All filters and fluid level indicators are within easy reach

For those times when the surface is way out of level and the coach requires more leveling than the air bags can deliver, hydraulic leveling jacks are also included. These jacks are made by Equalizer Systems and are powered in both directions. Rather than use springs to retract them, the system utilizes two-way hydraulics to power them back into place. This results in a more positive retraction and faster return times.


All Entegra Coaches utilize a 2x4 wooden floor structure that is located over the top of the typical steel framed substructure. This helps to deaden any road noise, because the wood acts as a buffer to absorb and deaden any road noise or vibrations. It also provides additional room for insulation and gives every Entegra Coach an industry leading R-33 insulation value. An in-floor hydronic heating loop ensures that the ceramic floor tiles remain toasty warm on cool days or nights. Extensive insulation is also found in the front and rear caps, which is not the normal practice in the motorhome industry.


The Cornerstone spares no expense when it comes to decor. Our test coach was painted in the luxurious Opulence Black Cherry paint scheme that featured a four-color design laid over a metallic-silver background. The Cornerstone receives five coats of urethane clear for a total of eight to nine thousandths of an inch of clear coat, giving it a very deep look to its finish.


This particular Cornerstone was painted in the Opulence Black Cherry paint scheme, which featured a 4 color design overlaying a metallic silver background. 5 coats of urethane clear with a total depth of 8-9 mils delivers an attractive, deep look to its finish. The deep windshield and roll-off dash afford excellent vision in tight maneuvers and the chrome mirrors are mounted down low so that you have a good angle of view and also can see over the top of them, eliminating any blind spots. Large mono-blade wiper blades are fitted to fully enclosed arms that also house the windshield washers and shield them from the sun's harmful UV rays. Powerful Xenon headlights provide excellent illumination when driving at night.


The basement storage space is easily accessed by tall side hinged cargo doors. A generous 20" of clearance between the basement floor and bottom of the frame rails gives plenty of clearance for tall objects or containers. Powered slideout trays made access to cargo as simple as pressing a rocker switch.


Entegra uses frameless flush mounted windows with crank out awning style lower inserts. This gives an attractive upscale look and also minimizes wind noise when traveling. Girard Nova series power patio awnings are built into the upper fascia for a streamlined appearance and are capable of kicking down when extended to afford greater protection from the sun in the patio area. A power entrance door awning as well as window awnings are also standard. The power entry steps are of the sliding style common to higher end coaches, rather than the swing out style. The entry door is very easy to open, without requiring a stiff tug on the handle. This is due to a pneumatic locking cylinder that pulls the door tight against the seal whenever the parking brake is released. as soon as the parking brake is applied, the pneumatic plunger releases to relieve tension on the door latch for ease in operation. A 32" LCD TV is also located behind a weatherproof panel in the patio side of the coach. A DVD player and speaker system completes this entertainment center that is perfect for outside entertaining.


12 volt coach needs are met by a bank of 8 AGM batteries, which are more than adequate to power the dual Magnum true sine wave inverters. A set of two battery mounting trays are mounted on slide rails to allow easy access.

Both interior heat and domestic hot water heat are provided by an Aqua Hot hydronic heating system. The boiler is located in a driver side basement compartment and can be heated by electricity or the diesel burner. In addition to the two interior zones, the Aqua Hot system also provides hydronic in-floor heating as well as basement heat to prevent any plumbing freeze-ups in cold weather.

Air conditioning needs are met by three 15,000-BTU rooftop units with heat pumps. The units are ducted and feed a series of registers through-out the coach. The air conditioner return air in the main living area was fed through a mirrored and hardwood trimmed intake duct to provide quiet airflow when running. Indeed, it was one of the quietest coaches we've been in and when all three air conditioners were running it was easy to hold a conversation in normal speaking tones.


The Cornerstone's full house water filtration system ensures that clean water is available at every location. The 50-amp electrical service is fed by shore hook-ups or a 12,500-watt Onan Quiet Diesel generator, which is located on a slide out tray in the front cap. An Onan EC-30 Automatic Generator Start system can be energized to auto start the generator whenever shore power is not available and battery voltage is below a certain threshold or the thermostat is calling for air conditioning.

Lighting throughout the coach was controlled by multiplex lighting controllers. You can create specific scenes to your own taste and save them to allow instant recall of any lighting scene from various locations within the coach. The powered sun and privacy shades were also controlled by these control panels. An optional iPad can be used to send wireless signals to this system to control lighting and shades from any location in the coach.


The slideouts and entry door are flush when retracted to minimize wind noise. The paint stripes are continued around the edges of the slideouts to offer a flowing look to the decor.



The Cornerstone's interior is another area where things are kicked up a notch. While the norm in most coaches is Flexsteel furniture with thin Ultra Leather material, the Cornerstone uses upscale Villa Natural Leather furniture. The woodwork is stellar to say the least. All of the Amish craftsmanship was evident in every piece of cabinetry or millwork, which was fit to perfection. From the polished ceramic tile floors to the vinyl padded ceiling, attention to detail was the order of the day.


The cockpit area is well laid out. A color monitor views the rear camera, as well as the two side-mounted cameras that auto sequence with the turn signals. A radio/CD/GPS navigation system is located directly above. The dash is finished with burl wood panels and the driver's side console controls the usual array of switches for the engine brake, tag axle dump, auxiliary lighting, step well cover, and power sun visors.

The parking brake is mounted on the vertical dash to prevent pets from accidentally stepping on it and releasing the brakes. The Spartan gauges and information center are easy to view through the fully adjustable Smart Wheel. The integral seat belts are fed through slits in the six-way power seats, making it easy to buckle up. The Cornerstone also includes the TripTek trip computer system and a remote compass/temperature display.


The couch and dinette ensemble are a wrap-around design that ties the comfortable booth dinette in with the sleeper sofa. Two large drawers beneath the booths provide additional storage space.

Our coach was equipped with Washington Glazed Cherry cabinetry and one of three decor packages. The sofa-couch, love seat, and dinette booth were all equipped with large pull-out drawers to maximize interior storage space. The love seat on the passenger side can be replaced with an optional desk and recliner or dual recliners if desired.

A mirrored cabinet mounted to the exterior wall in the guest bath contains various environmental controls as well a fuse panel for the various 12 volt circuits.

A mid-ship entertainment center cabinet holds a 40" LCD TV, satellite receiver, DVD player and other entertainment gear. An electric fireplace adds a bit of ambiance and also provides for additional interior heat.


Entegra galley layouts vary from floorplan to floorplan but every galley area will have hardwood cabinets and Corian solid surface countertops with a porcelain tile backsplash. High end appliances and Price-Pfister faucets are used. The Fisher-Paykel dishwasher is trimmed with a custom made panel. A convenient pull-out work area adds additional space for food preparation and is located next to the Whirlpool residential refrigerator. This 21 cu ft unit features an an-door ice dispenser and filtered water dispenser and is powered through one of the two Magnum true sine wave inverters.

This silverware drawer is typical of Entegra cabinetry. Every drawer features heavy metal drawer slides and hardware. This particular silverware drawer featured a sliding top section that exposes additional storage beneath. The silverware tray can be removed by simply lifting it out

Alongside the Fisher-Paykel dishwasher that is mounted beneath the galley is a large pull-out shelf unit with an integral wastebasket and holder

The guest bath is located mid-ship and features a vanity with recessed sink as well as a water closet in an enclosed room.

Immediately opposite the hall is a cabinet with louvered doors that house the stackable washer-dryer. Trips to the campground laundry are a thing of the past with the Cornerstone


The bedroom's king bed holds a Select-Comfort air mattress and is flanked by solid surface nightstands. Multiplex lighting controllers are located on the wall and in the overhead cabinet to provide convenient access to lighting controls. The bedroom is separated from the rear bath and front hall and bath by sliding pocket doors that utilize pneumatic solenoids to lock in place whenever the parking brake is released to prevent slamming when traveling.


Opposite the bed, a slideout contains overhead cabinetry which also holds an LED TV. The lower Corian topped dresser contains storage drawers as well as a clothes hamper.

The spacious rear bath layout places a vanity in the passenger side slideout. The mirror is attractively decorated but there are no hinged makeup wings nor is there a medicine cabinet

The driver side rear bath contains a circular shower surround with clear glass to accent the ceramic tile inside

The rear bath is a slight step up from the bedroom. The attractive porcelain tiled shower area is surrounded by a circular glass shower enclosure with sliding circular doors that operate in tracks rather than swing out and drip on the floor. A macerator style commode is mounted to the porcelain bath flooring. The rear of the bath gains access to the full width rear wardrobe. Opposite the shower is a solid Granite vanity with dual sinks. An enclosed water closet next to the shower handles those necessary tasks. At the rear of the coach is a full-width aromatic cedar lined wardrobe with cavernous storage. The wardrobe doors also utilize the pneumatic lock cylinders to hold them in place when traveling.

Road Test

Once we were thoroughly acquainted with the Cornerstone and its features and controls it was time to hit the road. The 600hp Cummins ISX was a whole new experience and the Cornerstone quickly came up to speed. With 1,950 lb-ft of torque, losing speed when climbing a grade is a thing of the past. The disc brakes on all three axles easily hauled the coach to a stop.

Maneuverability was excellent. It seems like all Entegra coaches handle just a bit better than the typical coach. The addition of their X frame bracing and structural upgrades just allow the suspension to do its job that much better, while still offering the smooth ride one would expect from a coach of this caliber.

The chassis stiffening, plus the wooden floor sub-structure, absorbed any jolts from potholes or vibrations from the road. The suspension did all of the work and the coach body just rode along as smooth as can be. The noise from the road was dampened by the floor structure and high levels of insulation. Clean aerodynamics, especially noticed in the flush mounted windows, further reduced any noise at highway speeds. When you combine the handling with the quiet ride that we experienced the Cornerstone is truly the benchmark that will be hard to beat.

Cornerstone 45K Floorplan


2013 Entegra Coach Cornerstone 45K

Standard Features:

  • Three 15,000 BTU AC units with heat pumps
  • 23 cubic inch residential refrigerator with ice and water dispenser
  • 40" midship LCD TV with entertainment center
  • 26" front overhead LCD TV
  • Six way power cockpit seats with integral lap and shoulder belts
  • Two burner electric glass cooktop with convection microwave oven
  • Dual 2800 and 2000 watt pure sine wave inverters with 8 AGM batteries
  • 32" bedroom LCD TV
  • Winegard in-motion satellite dome
  • In-dash GPS navigation system
  • Hadley air leveling system
  • Equalizer Systems dual acting leveling jacks
  • 32" exterior LCD TV in galley slide
  • Aqua-Hot hydronic heating system
  • Onan 12,500 watt diesel generator
  • Fisher-Paykel dishwasher drawer
  • Stackable washer/dryer
  • Built-in central vacuum system with dust pan
  • King bed with Select Comfort Mattress
  • Sony surround sound system

Price as Tested $557,721 (MSRP)


Gross Vehicle Weight: 50,600 lbs.
Gross Combined Weight Rating: 65,600 lbs.
Trailer Hitch Capacity: 15,000 lbs.
Wheelbase: 320 inches
Overall Length: 45 feet 1 inch
Overall Width: 101 inches
Overall Height: 12 feet 11 inches
Fresh Water: 100 gallons
Gray Water: 60 gallons
Black Water: 60 gallons
Chassis: Spartan K3 rear engine diesel
Front Axle: 16,600 lb IFS, Air-ride
Drive Axle: 23,000 lb Air-ride
Tag Axle: 14,000 lb Air-ride Brakes: Air disc, all three axles
Fuel Tank: 150 gallons
Trailer Hitch Capacity: 15,000 lbs.
Engine: Cummins ISX15 with 3 speed compression brake
Horsepower: 600 HP at 1,800 RPM
Torque: 1,950 lb-ft at 1,400 RPM
Transmission: Allison 4000 series 6 speed automatic


Entegra Coach
(800) 945-4787

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