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2016 Entegra Cornerstone 45A

An In-Depth Review of Entegra Coach's Flagship Motorhome
Article Date: January, 2016


Entegra Coach is one of the fastest growing motorhome manufacturers in the Class-A diesel pusher market. With a reputation for quality and customer service that goes well above the norm, this is understandable. Like most RV manufacturers, Entegra has made the usual upgrades in features and amenities with every new model year. But 2016 was a major redesign, featuring redesigned front and rear caps styled to a more modern look. I have to admit that I've admired Entegra's construction and quality since I first took a serious look at them back in 2010. But this time the floorplan as well as the features just all came together for us. We sold our previous motorhome and bought an Entegra Coach. In fact the 2016 Cornerstone reviewed in this article is the one that Leann and I now happily own.

Building a quality product the right way does take time and it takes seven weeks to build an Entegra Cornerstone. Three weeks are dedicated to the basic build of the coach while the next three weeks are spent in the paint shop. The final week is devoted to Final Fit and Finish as well as extensive quality control inspections. The result is a quality built coach that is ready to spend time in the new owner's hands rather than at the dealership correcting manufacturing errors. I was afforded the rare opportunity of being allowed to follow my coach down the assembly line during the build process. I've written an article about that, with extensive photos at This Page for more details, but for now, I'll just concentrate on the finished coach.


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 largest chassis - the K3. The Spartan K3 is a tough chassis, capable of containing all of the stress of a large motorhome with a massive 15 liter engine yet still delivering a smooth ride and excellent road manners. Entegra kicks that up a notch with a number of custom chassis tweaks that make this coach a real joy to drive, such as additional X bracing that further stiffens the frame and provides a solid surface to mount the coach on. The end result is a chassis that doesn't flex and a superstructure that will not twist and loosen up over time.

Click Here to view the 2016 Cornerstone chassis spec sheet.

The Cornerstone is powered by a Cummins ISX 15 liter engine that produces 600 HP and 1,950 ft-lbs of torque. To some this might seem like overkill but when climbing mountain grades or trying to accelerate up to speed on a busy Interstate's entrance ramp this engine is a welcome relief. You would think that this might be a costly engine to operate when it comes to fuel economy but in fact, it is not that thirsty. The big engine has so much torque that it never has to work hard and the lower gear ratio of the drive axle allows the engine to lope along at a lower RPM. The end result is that it gets the same fuel economy as the smaller 450 HP ISL 9 liter engines under most driving conditions. Large 365/70R22.5 Load Range L tires are fitted to the 20,000 lb. rated front axle while 315/80R22.5 Load Range L tires are fitted to the 20,000 lb. drive and 14,000 lb. tag axles. A 20,000 lb. towing hitch is standard and a 54,000 lb. GVWR and 74,000 lb. GCWR ensure that you'll have plenty of capacity to carry or tow anything you'll ever need. Six wheel disc brakes and the three speed engine compression brake do an amazing job of stopping this coach in short order.

The coach is equipped with Hadley SLS Active Air suspension system. This computer controlled system will adjust the suspension air bags while you drive to level the coach automatically to eliminate crown-of-the-road leaning and other artifacts. This system can also level your coach when parked so that you don't have to deploy the leveling jacks when pulling into a rest area or when parked on soft ground or hot asphalt. It also has the ability to raise or lower the ride height of the coach if you need a bit more clearance when parking or maneuvering at slow speeds. The Cornerstone is also equipped with an Equalizer Systems dual acting hydraulic jack leveling system for those times when you wish to use jacks.

/articlepics/73_2016_cornerstone_image-10.jpg Entegra Coach utilize a thick wooden floor structure that is placed over the steel framework and filled with Flex Foil and fiberglass batt insulation that give it an impressive R33 insulation value. Pex tubing for the hydronic heated floor is also installed. The wooden floor also helps to dampen noise and road noise.

All Entegra Coaches utilize a 2x4 wooden floor structure topped with 3/4" exterior plywood 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. The 2-1/2" thick sidewalls are fitted with 1/2" plywood on the interior and reflective flexfoil insulation and vapor barriers are installed before the fiberglass batt insulation, an acoustic grade found in high end studios, is installed. Extensive insulation is also found in the front and rear caps, which is not the normal practice in the motorhome industry. After camping in 97 degree Texas heat and heating the coach in cold Wisconsin weather we've found that the insulation and tight seals made the coach much more comfortable than we were used to. Our air conditioning and heat ran half as much as in our previous coach and the coach was much quieter, both when driving and when parked in a noisy location.


The Cornerstone spares no expense when it comes to looking good. Our coach was painted in the Topaz paint scheme that featured a detailed graphic inlay design on a black background. Five coats of urethane clear cover this paint with a total of eight to nine thousandths of an inch of clear coat, giving a very deep look to its finish. Of course the newly redesigned front and rear caps make a huge difference this year. The bright Xenon headlights flank a stainless steel Entegra emblem that is backlit by LED lighting. The headlights are surrounded by C shaped LED accent lighting. The rear cap now sports LED taillights that are set in similar stainless steel bezels that are surrounded by red LED accent lighting. The stainless steel rear emblem is backlit by red LED lighting. Stainless steel trim is applied to the lower edge of the cargo bay doors on both sides of the coach. The rear engine access cover is now operated by a power lift mechanism for easy access.


Frameless flush mounted windows adorn the sides of the coach, giving it a smooth, attractive look. These windows are now fully opening in the 2016 Entegra line. New dual Girard power patio awnings are built into the upper fascia down the entire patio side of the coach and offer a streamlined appearance. These new awnings now are multi-angle and will extend out, then drop down near the end of their travel to afford maximum shade from the sun. 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 excessive force when pulling on the handle because a pneumatic locking cylinder pulls the door tight against the seal whenever the parking brake is released. When the parking brake is applied, the pneumatic plunger releases to relieve tension on the door latch for ease in operation. A 32" LED TV is also located behind a weatherproof panel in the patio side of the coach and is equipped with a J B Lansing sound system with multiple input sources. Entegra slides are flush to offer a clean look and no window noise or air leaks when traveling.


The Cornerstone's electric power needs are met by a number of sources. A 50 amp power retract cord reel provides easy access to campground power while a 12,500 watt Onan Quiet Diesel generator can handle the entire coach when shore power is not available. A pair of Magnum true sine wave inverters provides an additional 4,800 watts of clean power to operate the entertainment system, electric outlets, refrigerator, microwave and other electrical accessories without requiring the generator to be run. An Onan EC30 automatic generator starting system will automatically start the generator when dry camping if the battery voltage gets too low or if the thermostat calls for cooling. Battery power is provided by eight 6 volt AGM batteries, mounted on two sliding trays for ease in access.

/articlepics/73_2016_cornerstone_image-2.jpg The power cord reel and Aqua-Hot boiler are located in a driver-side compartment for easy access.

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 ducting provided even, consistent air flow throughout the coach and was whisper quiet. The thermostat controls both the cooling and heat pump modes and also the Aqua-Hot hydronic heating system. The Aqua-Hot system utilizes a boiler that is heated by a diesel burner, an electric heating element, or by the engine's hot coolant when driving. The boiler circulates hot anti-freeze through heat exchangers located throughout the coach as well as the basement. In addition, the boiler also feeds the heated tile floor loop that gives you nice warm floors on those cool mornings. An engine preheat system is the final feature of this system.

The plumbing system has been redesigned for 2016 on every Entegra Coach. New holding tanks offer additional gray tank capacity and the new Sanicon Turbo macerator will dump much faster than older models, easily matching the speed of a gravity dump. The macerator hose is located in a separate compartment and extends to 21', although extension hoses can extend this considerably. A bypass port is also located for those who would rather use a 3" slinky hose to dump their holding tanks. A redesigned wet bay panel contains switches for the electric holding tank dump valves, a connection for the black tank flush, paper towel and soap holders, as well as an outside faucet connection with a self-retracting coiled hose. A power retract hose reel hides behind the panel and is fed through a roller guide. The whole house water filter is augmented by a dedicated filter for the refrigerator and galley sink water dispenser to provide additional water filtration for drinking water.

/articlepics/73_2016_cornerstone_image-19.jpg The utility bay was completely redesigned for 2016.

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 MCD 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 45A floorplan is new for 2016. Our coach was finished in the Mocha decor package with natural cherry woodwork. Every Entegra Coach is fitted with cabinetry built with the finest Amish craftsmanship and the Cornerstone takes this to an even higher level with millwork that features extensive tooling. The ceiling treatment has mirrored insets that surround a decorative LED backlit translucent panel that is framed in cherry woodworking. The porcelain tile floor features an ornate hand laid tile inset in the main living area. All of the cabinetry is fitted with quartz tops and LED lighting is hidden beneath the perimeter edges of all fixed counter tops to provide an attractive look. The Cornerstone uses real Leather furniture with stylish brass rivets for the 82" sofa-bed as well as the cockpit seating.

The passenger side main slideout holds an 82" genuine leather sofa-bed trimmed with brass rivets, a dinette, the residential refrigerator and a large storage pantry.

The driver-side slide holds the desk, entertainment center and galley.

The cockpit area is laid out with the driver in mind. A color monitor displays 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 and uses the Rand McNally GPS software designed for RVs. 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 6 way heated seats are very comfortable and come with power foot rests. The driver's seat footrest has a lockout feature so that it can only be extended when the seat is rotated around to face the living area. 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, which is also equipped with paddle controls to operate the entertainment system. USB jacks are located in the dash to interface the entertainment system with an iPod or other MP3 player. The Cornerstone also includes the TripTek trip computer system.

/articlepics/73_2016_cornerstone_image-21.jpg The driver's station is designed with comfort and usability in mind

The entertainment center is first class in the Cornerstone. A Bose surround sound system is used to select the various input sources, such as cable TV, satellite TV, Blu-Ray player, off-air broadcasting antenna, dash entertainment system, etc. It then sends the selected source to the four LED TVs located throughout the coach. A 32" TV is located in the front overhead cabinetry, another 32" TV is located in the bedroom area, a 40" TV is located in the exterior enclosure in the patio area, while a 50" 3D Ultra-HD Smart TV is located in the desk. The bedroom TV also has its own Blu-Ray player, a Bose sound bar and the provision for a second satellite receiver or DVR. The off-air antenna is the new Winegard Rayzar Automatic. This unit is located in a domed structure on the roof of the coach and never needs to be raised or lowered. The remote control panel allows you to locate any nearby stations easily and provides a good strong signal. Our coach was equipped with the Winegard Trav'ler automatic satellite dish but an in-motion dome is also available.

/articlepics/73_2016_cornerstone_image-14.jpg The desk features a 50" TV on a power lift mechanism.

One key feature of the new 45A floorplan is a functional desk. This large desk serves many functions and contains an electric fireplace that is flanked by a set of desk drawers, including one designed for hanging file folders. Directly above is a pair of wide storage areas with flip-down drawer fronts that hold the various electronic components for the entertainment center. This is where the Blu-Ray player and any satellite receiver or DVR will be located. It's also the home for the Bose surround sounds system main unit and the controller for the Winegard Trav'ler satellite dish. One key feature of this desk is that it contains the 50" UHD Smart TV that is mounted on a power lift mechanism. This TV is in the perfect location for viewing from within the coach, especially from the couch directly opposite it. When not in use it can be lowered and retracted into the desk, giving a flush desk top and an excellent view out the 60" wide window behind it. A Bose sound bar is part of the surround sound system and is mounted on top of the window valance directly above the TV. The desk features a cutout area for a keyboard or laptop computer and a comfortable desk chair. An optional mantelled fireplace and recliner are available in lieu of the desk.

The desk contains compartments for the entertainment center equipment, a fireplace and desk drawers.

The desk has a retractable keyboard tray for a comfortable work environment.

The galley in the 45A is the largest offered by Entegra Coach and a real treat for any cook. Hardwood cabinets are found above and beneath the quartz surfaced galley. A convection microwave is installed in the overhead cabinetry while the Fisher-Paykel drawer style dishwasher is installed beneath the counter in trimmed with a custom cherry panel. A dual basin stainless steel sink is equipped with quartz inserts that are fitted with a poly cutting board material on the backside so that they can be reversed and used as cutting boards if desired. An induction cooktop is flush mounted on the countertop. A convenient pull-out work area adds additional space for food preparation and is equipped with four deep drawers to maximize storage space. Directly opposite the galley work area is a Samsung 22 cu. ft. residential refrigerator which features an an-door ice dispenser and filtered water dispenser. The fridge is powered through one of the two Magnum true sine wave inverters to allow it to cool its contents when driving or when parked without power. Immediately next to the fridge is a huge pantry area. A pair of large slide-out pantry trays make up the top half of this expansive storage unit while a drawer and large pull-out single pantry make up the lower portion, offering plenty of space for food storage. The dinette is built into a thick buffet cabinet and pulls out to easily make enough table space for four persons. The cabinetry in the buffet also includes a cabinet that can be used for a printer and features a slideout shelf and access to electricity.

/articlepics/73_2016_cornerstone_image-8.jpg The large residential fridge is flanked by a spacious pantry.

The coach's mid bath holds a large mirrored vanity cabinet, a vanity with flush mounted sink and a Tecma macerator toilet. various electronic systems are located behind a side mirror in the vanity and contain the thermostat, Aqua-Hot controls, See Level digital tank monitoring system and the G5 Firefly multiplex wiring system master unit and power distribution center.

/articlepics/73_2016_cornerstone_image-9.jpg The mid-bath contains a macerator style toilet, quartz vanity with recessed sink bowl and a medicine cabinet.

The bedroom's king bed is adorned with a Tempurperdic Cloud mattress, which has been the best mattress we have ever slept on. Small quartz topped nightstands flank the bed and various controls are placed in the bottom of the overhead cabinetry to operate lighting, the large ceiling fan, a remote entry door lock-unlock switch, LED reading lamps and a generator start-stop switch.

/articlepics/73_2016_cornerstone_image-10.jpg The king size bed is fitted with a Tempurpedic Cloud mattress.

The opposite end of the bedroom holds cabinetry that contains a 32" LED TV that is hinged to afford access to a second Blu-Ray player and satellite receiver or DVR. There is plenty of room for storage and a digital safe in also mounted in this area.

/articlepics/73_2016_cornerstone_image-11.jpg The 32" LED TV in the bedroom slide-out is hinged to allow access to storage behind.

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

The rear bath is a major change from previous rear bath designs. Most rear baths have a 5" step up between the bedroom and bath to accommodate the increased height needed to clear he engine. However, the 45A bathroom floor remains at the same level as the rest of the coach until the last few feet, when it steps up at the rear laundry center and macerator toilet. This gives you maximum height in the main bath area so that even the tallest person can take a shower with plenty of headroom. The spacious 36" x 46" shower if fitted with ceramic tile and a glass shower surround. We found it roomy enough to give our large German Shepherd a bath while both the dog and I comfortably remained inside the shower stall. Opposite the shower is the 46" wide bathroom vanity. A large mirrored medicine cabinet spans the full width of the vanity and provides tons of storage space for necessities. After this point the porcelain tile floor does raise up for those last few feet. The macerator style toilet is located on your right and the stackable laundry center is located in another Amish built cabinet with louvered doors on your left. This then exposes the full width rear wardrobe which is lined with aromatic cedar.

The spacious rear bath contains a vanity with large medicine cabinet and laundry center on the curbside.

The opposite side of the rear bath contains a large tiled shower and a macerator toilet. A full width wardrobe spans the entire rear of the coach.

Driving Impressions

Driving the Cornerstone is a real treat. Entegra promotes their coaches as "The Quietest Riding, Best Handling Coach on the Market Today. Period." That's a tall claim but after spending some seat time in the coach we found that to be 100% true. We expected to be impressed but never would have guessed it would have been as impressive as it was. Obviously the first thing that anyone thinks about is that 600hp Cummins ISX engine. With 1,950 lb-ft of torque, losing speed when climbing a grade is a thing of the past and the 600 HP really does make a difference when attempting to safely merge onto a busy freeway where you need to get up to speed fast.

But the horsepower was only part of the lure of the Spartan K3 chassis. Braking was equally impressive. The six wheel disc brakes brought the Cornerstone down to a stop in short order. Having discs on the rear axles instead of drums also helped to eliminate the brake fade common to drum brakes when they get hot. When stuck in stop and go traffic where progress was a few feet at a time the brakes just continued to stop as if new without any fade. Also, when descending the 10% grade Teton Pass the combination of the three speed engine compression brake and the six wheel disc brakes made it an effortless descent down this steep grade and switchbacks.


Handling was equally impressive. 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 combination of the K3 chassis, Entegra's additional bracing, 62mm Bilstein shocks and those fat 365 series front tires made this coach handle and drive like a dream. It didn't' seem to mind what was underneath the tires. Typically, road artifacts, such as a construction zone with lane shifting, and ridges or pavement breaks will nudge or shove the coach off to one side because the coach or its tires just don't want to ride on anything that isn't nice and flat. But the Cornerstone didn't seem to care. It just drove wherever I aimed it and was the most stable ride I've ever experienced. It imparted a real feeling of security and safety. I've often commented that this was the biggest sports car I've ever driven. However it also combined a smooth and quiet ride, which is something you don't find in your typical sports car.

Lastly, there is Entegra's forward control cab design. Entegra coaches all use the largest front windshield available in a class A motorhome. This windshield runs lower than the typical windshield and Entegra's forward seating position gives the driver the ability to see right in front of the coach without the blind spots typical to a higher windshield base. This is a huge benefit when maneuvering into a tight area or negotiating a tight turn because you can see how much room you have at the front and corners of the coach. Another benefit is that the lower windshield allows the mirrors to be mounted lower than usual. This allows the driver to see over the top of them to eliminate any blind spots, especially at intersections, which can be a safety concern. The lower mirror location also allows a better angle of view so that you can see back farther down the road while still retaining a view of the rear tires, unlike the eye-in-the-sky view common to mirrors that are mounted higher. The combination of the driver's position, comfortable seat, instrument panel arrangement and windshield made the driver's position perfect for those long drives with no fatigue.

Living in the coach was another surprise. The coach is so well insulated and free of drafts that you might be in for a shock when you step outside and find out what it's really like out there. We stepped outside to the strong odor of a nearby forest fire but never knew it was there from inside the coach. Any outside noise just seems to go away once you enter the coach and the coach's heating and cooling systems work quietly and effortlessly to keep you comfortable in any weather. Entegra's attention to detail when insulating this coach have really paid off. All in all Entegra has really hit a home run with this coach.

Cornerstone 45A Floorplan


2016 Entegra Coach Cornerstone 45A

Standard Features:

  • Quartz countertops
  • Topaz full body paint
  • Mocha interior with leather furniture and natural cherry woodwork
  • MCD power roller shades, privacy and sun screen
  • Winegard Rayzar Automatic TV antenna
  • Dual Girard Multi-Angle power patio side awning
  • Girard power entry door awning
  • Girard window awnings
  • Sanicon Turbo system
  • Power cord and hose reels
  • Basement freezer and slide tray
  • Dual full width power cargo slide trays
  • Three 15,000 BTU AC units with heat pumps
  • 22 cubic inch residential refrigerator with ice and water dispenser
  • 50" Ultra-HD LED Smart TV with power lift
  • 32" front overhead LED TV
  • Bose Surround Sound System with Blu-Ray Player
  • 40" LED bedroom TV with Blu-Ray player and Bose sound bar
  • 40" exterior LED TV and JB Lansing sound system in galley slide
  • Six way heated 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
  • Winegard Trav'ler automatic satellite dish
  • In-dash entertainment system with Rand McNally TripMaker GPS navigation system
  • Hadley SLS air leveling system
  • Equalizer Systems dual acting leveling jacks
  • 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 Tempurpedic Cloud Mattress

Price as Tested $630,997 (MSRP)


Gross Vehicle Weight Rating (GVWR): 54,000 lbs.
Gross Combined Weight Rating (GCWR): 74,000 lbs.
Net Cargo Carrying Capacity (NCC): 9,300 lbs.
Trailer Hitch Capacity: 20,000 lbs.
Wheelbase: 320 inches
Overall Length: 44' - 11"
Overall Width: 101 inches
Overall Height: 12 feet 9 inches
Fresh Water: 100 gallons
Gray Water: 63 gallons
Black Water: 42 gallons
Chassis: Spartan K3 rear engine diesel
Front Axle: 20,000 lb IFS, Air-ride
Drive Axle: 20,000 lb Air-ride
Tag Axle: 14,000 lb Air-ride Brakes: Six wheel anti-lock disc brakes
Fuel Tank Capacity: 150 gallons
DEF Tank Capacity: 15 gallons
Engine: Cummins ISX15 with 3 speed compression brake
Horsepower: 600 HP at 1,800 RPM
Torque: 1,950 lb-ft at 1,200 RPM
Transmission: Allison 4000 series 6 speed automatic


Entegra Coach
(800) 517-9137

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