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Newmar Mountain Aire Motor Home Class A - Diesel RVs For Sale

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The Mountain Aire Class A diesel motorhome by Newmar allows you to take luxury with you where you want to go! You can rest and relax inside from the cockpit to the cabin with features that provide the perfect combination of form and function. 


The coaches offer on-site dining with a fully equipped kitchen with super polished solid surface countertops, feature raise-panel doors with soft-close hinges, and a large pantry for those longer trips, plus much much more!. Each is built exclusively on the Spartan K3 tag axle chassis with 500 HP and 1,695 lb./ft. of torque making it easy to travel up hills and while towing.  The Comfort Drive adaptive steering and standard Mobileye lane tracking, the tire pressure monitoring, the electronic stability control and OnGuard collision mitigation technology among other features provide safety on the road.


Why would you choose a Mountain Aire Class A diesel motorhome by Newmar to travel the country? Because you enjoy the finer things in life!

  • Mountain Aire 4551

    Mountain Aire 4551 Floorplan Image

    Newmar Mountain Aire Class A diesel motorhome 4551 highlights: 87" Hide-A-Bed ... more about Mountain Aire 4551


    Sleeps 6
    Slides 3
    Length 44 ft 10 in
    Ext Width 8 ft 6 in
    Ext Height 13 ft 2 in
    Int Height 6 ft 11 in
    Interior Color Avalon, Beckford, Hamden, lbis
    Exterior Color Avalon, Beckford, Hamden, lbis
    Hitch Weight 15000 lbs
    GVWR 54000 lbs
    Dry Weight 45300 lbs
    Cargo Capacity 8700 lbs
    Fresh Water Capacity 105 gals
    Grey Water Capacity 80 gals
    Black Water Capacity 60 gals
    Furnace BTU 50000 btu
    Generator 12.5 kW Cummins Onan Diesel
    Fuel Type Diesel
    Engine Cummins
    Chassis Spartan K3 Tag Axle
    Horsepower 500 hp
    Fuel Capacity 150 gals
    Wheelbase 294 in
    Available Beds King
    Torque 1695 ft-lb
    Refrigerator Type Whirlpool
    Refrigerator Size 19.7 cu ft
    Convection Cooking Yes
    Cooktop Burners 3
    Shower Size 50" x 34"
    Number of Awnings 2
    Axle Weight Front 20000 lbs
    Axle Weight Rear 20000 lbs
    Axle Weight Tag 14000 lbs
    LP Tank Capacity 22 gals
    AC BTU 45000 btu
    TV Info LR 50" Samsung 4K LED on Lift, Cab 43" Samsung 4K LED, BR Samsung LED
    Awning Info Nova Side
    Washer/Dryer Available Yes
    Gross Combined Weight 69000 lbs
    Shower Type Shower w/Seat
    Electrical Service 50 amp

    Similar Floorplans

Mountain Aire Features:

Standard Features 



  • Full-Paint Masterpiece Finish™ with Cut & Buff with Beta Fusion Protection on Front Cap
  • Lighted Newmar Badge in Front Grill
  • Convex Exterior Mirrors with Remote Control, Defrost, Turn Signals and Side View Cameras
  • Chrome Power Baggage Door Locks, Keyless Entrance Door with Touch Pad and Door Bell
  • Entrance Door with Automatic Step
  • Rear Hitch for Towing Car
  • Assist Handle at Entrance Door
  • Mud Flaps
  • Rear Protective Tow Guard with Stainless Steel Newmar Name Cutout
  • Undercoating
  • Hydraulic Leveling Jacks
  • Stainless Steel Exterior Trim Pieces and Entrance Door Kick Panel
  • Hammock Backer
  • Storage Bins in Pegboard Compartment
  • Storage Shelf Above Freezer


  • Patio Hammock Package Specify 1 or 2
  • Stainless Steel Trim Kit for Exterior Compartment Doors
  • Flag Pole Bracket
  • Storage Tray 26 X 90 Power Location-Bay 2
  • Storage Tray 26 X 91 Non-Power, Location Bay 2
  • Storage Tray 40 X 90 Power, Location-Bay 2
  • Storage Tray 40 X 90 Power, Location-Bay 3
  • Storage Tray 42 X 91 Non-Power, Location-Bay 2
  • Storage Tray 42 X 91 Non-Power, Location-Bay 3
  • Storage Tray 43 X 56 Non-Power, Location-Bay 3
  • Storage Tray 43 X 56 Non-Power, Location-Bay 4


  • Fiberglass Roof and Integrated Gutter Rail
  • Gelcoated Fiberglass Exterior Sidewalls, Front and Rear Caps
  • Aluminum-Frame Sidewalls & Roof Construction, 16" on Center
  • 5/8" Foam Insulation Laminated in Sidewalls & Ceiling
  • Polar Pak R19 Batten Insulation on Roof
  • R16 Foam Insulation in Basement
  • Automatic Mechanical Lock Arms on Non Hydraulic Slideout Rooms-Paddle Style
  • Egress Door with Ladder System


  • Spartan K3 Tag Axle 500 HP
  • Air Leveling System
  • Aluminum Wheels
  • Electronic Chassis Information Center in Dash
  • Electronic Stability Control
  • Cruise Control
  • Comfort Drive™ Steering with Power Column & Adjustable Control
  • Recessed Fuel Fills with Crossover to Fill from Either Side
  • Back-Up Alarm
  • Anti-Lock Braking System
  • Chassis Battery Disconnect
  • Automatic Headlights ON/OFF
  • Push Button Engine Start
  • Glass Dash Instrumental Panel
  • On Guard Collision Mitigation Adaptive Cruise System with Adj. Following Distance Control on Spartan Chassis
  • Tire Pressure Monitoring on Tag Axle Chassis
  • Mobile Eye Lane Tracking and Lane Departure Warning System


  • Curt Spectrum Integrated Brake Control on Spartan Chassis

Mechanical and Electrical

Windows, Awnings, and Vents

  • Frameless Double-Pane Tinted Safety-Glass Windows
  • Fantastic® Vent with Rain Sensor in Kitchen, Bathroom and Enclosed Stool Room
  • Hardwood Louvered Cover on Fantastic® Vent in Kitchen
  • Skylight Above Shower*
  • Girard Package-Two Nova Side Awnings, Slideout Covers, Entrance Door & Power Window Awnings
  • One Piece Tinted Windshield
  • Driver Side Power Window
  • Large Non-Ventilated Living Room and Dinette Windows


  • Bunk Windows
  • Kitchen Window

Air Conditioning and Heating

  • Three 15M Penguin™ Heat Pump Central Air Conditioners with Remote Control Thermostat
  • Chinook Dual Loop Heat with Continuous Hot Water
  • Dash Heater and Air Conditioner
  • Driver & Passenger Dash Overhead Ventilation System
  • Wall Mounted Sensors for Heating and Air Conditioning
  • Roof Air Conditioning Drainage System
  • Electric Radiant Heat Installed Below Main Floor Tile


  • 12.5 Kw Cummins Onan® Diesel Generator
  • 50 Amp Electrical Service with Flexible Cord with Automatic Transfer Switch
  • Six 6-Volt House Batteries
  • Battery Disconnect Switch for House Battery
  • 10 Watt Solar Panel to Charge Chassis Battery
  • 3000 Watt True Sine Inverter
  • 12 Volt Auxiliary Receptacle on Dashboard
  • Emergency Engine Start Switch
  • Engine Block Heater
  • Energy Management System
  • Exterior Security Lights
  • Midship Side Turn Signals
  • LED Lights Recessed in Ceiling and Underneath Overhead Cabinets
  • Accent Lights in Feature Ceiling, Slideout Fascia Trim and Lambrequins
  • LED Lighting in Pull Out Pantry, Kitchen and Bathroom Base Cabinets
  • LED Lights in Exterior Storage Compartments on Automatic Switches
  • LED Lights Installed Under Door Side Slideouts
  • Lights in Wardrobes
  • Manually Operated Hold-To-Run Slideout Switch
  • Automatic Generator Start on Low Battery or Temperature Setting
  • Cable TV Connection
  • Interior Courtesy Lights
  • USB Charger at Dinette & Bedroom Night Stand
  • USB Outlet at Dash for Driver Use
  • Power Rewind Wheel with 50’ Cord*
  • Recessed Docking Lights
  • KIB Touch Screen Interior Light and Shade Controls
  • Secondary Multiple Touch Screen in Bedroom
  • All Lights Off Function in Bedroom
  • Silverleaf® Multiplex Electrical Wiring System
  • Solar Prep with Six Gauge Wire from Roof to House Battery Compartment
  • Spare Fuses in Chassis and House Fuse Panels
  • New Touch Screen Tank Display Monitor in Water Bay
  • Phone and Radio Controls on Steering Wheel on Spartan Chassis
  • Wireless Phone Charger Pad in Driver Area
  • Wireless Charging Mat Built into Passenger Console
  • 110 Volt Recept in Bed Overhead with Two Pass Through Ports
  • 110 Volt/USB Outlet at Head of Each Bunk*
  • Dimmable with Adjustable Aim Reading Lights at Head of Bed
  • Transfer Switch with Surge Protector


  • LED Strip Lighting Installed Under Off Door Side Slideouts
  • Four Flexible 100 Watt Solar Panels on Roof


  • Demand Water System
  • Sewage Holding-Tank Rinse
  • Dometic® 321 China Bowl Stool or Macerator Stool*
  • Aqua Miser Shower System
  • Tiled Shower Walls with Glass Door
  • Soap Dispenser in Shower
  • Fold Down Shower Seat
  • Water Filter for Entire Unit
  • Exterior Shower
  • Auto Fill for Fresh Water Tank
  • Power Water Hose Reel
  • Hot Water Line to Generator Area*
  • Grey Holding Tank Rinse


  • Assist Handle in Shower
  • RV Sanicon Turbo System


Cabinets and Furniture

  • Bermuda Glazed Maple Hardwood Cabinets with Raised Panel Doors with Matte Finish
  • Concealed Hinges on Cabinet Doors
  • Super Polished Solid Surface Countertop in Kitchen with Under Mounted Stainless Steel Sink and Sink Covers
  • Super Polished Solid Surface Countertop in Bathroom and Bedroom
  • Lifts on Bed Top
  • Passenger Seat Work Station
  • Pullout Pantry Shelves*
  • Push to Release Drawer Slides in Pantry
  • Soft Close Cabinet Doors*
  • Drawers with Dove Tail Sides with Self Closing Full Extension Ball Bearing Guides
  • Villa Ultra Leather Sofa and Driver/Passenger Seats with Integrated Seat Belts
  • Driver Seat with Vibrator for Haptic Feedback
  • Heated Front Seats with Power-Lumbar, Recline, Footrest & Queen Sized Passenger Seat
  • Plush Pillow Top Mattress*
  • Cedar Paneling in Bedroom Wardrobe
  • Extended Rotation Concealed Hinge for Washer/Dryer Cabinet Door
  • Side Folding Hide-A-Bed Sofa with Memory Foam Mattress*
  • Full Height Wardrobes Beside Lav*
  • Mesh Cell Phone Holder at Each Bunk Bed*
  • Molded Silverware Divider Tray


  • Glacier Glazed Maple Hardwood Cabinets with Raised Panel Doors with High Gloss or Matte Finish
  • Bermuda Glazed Maple Hardwood Cabinets with Raised Panel Doors-High Gloss
  • Toffee Glazed Maple Hardwood Cabinets with Raised Panel Doors-High Gloss or Matte Finish
  • Sable Maple Hardwood Cabinets with Raised Panel Doors-High Gloss Or Matte Finish
  • Sleep Number R5 Radius Corner Air Mattress
  • Power Extenda Flex Dinette
  • Buffet Dinette
  • Combination Desk/Dinette with Buffet Table, Two Fixed/Two Folding Chairs
  • Power Incline Retracting Bed Base with Sleep Number R5 Air Mattress
  • Power Incline Head of Bed with Sleep Number R5 Air Mattress
  • Euro Booth Dinette with Two Table Leaves and Two Folding Chairs
  • Euro Booth/Hide-A-Bed Combo 162” with Two Table Leaves & Two Folding Chairs
  • Two Recliners with Lampstand and Reading Lights
  • Two Ottomans*
  • Passenger Seat with Standard Width
  • Powered Theater Seating 87”


  • Stainless Steel 30” Convection Microwave with Recessed Three Burner Gas Cooktop
  • Air Horns
  • Whirlpool® 19.7 Refrigerator
  • Splendide Two-Piece Stacked Washer/Dryer
  • Dometic 2.47 Cf. Freezer on Pullout Tray in Exterior Baggage Compartment*
  • Dometic 3.0 Cf Freezer on Pullout Tray in Exterior Baggage Compartment*
  • Storage Shelf Above Freezer
  • Flush Cooktop Cover of Matching Countertop Material
  • Central Vacuum with Tool Kit


  • All Electric Recessed Mount Induction Cooktop and 8 AGM Batteries
  • Dishwasher in Drawer with Stainless Steel Front


  • Designer Feature Ceiling and Cathedral Ceiling with Added Height on Rear Bath Floorplans*
  • Tile Floor in Kitchen, Bathroom, Bedroom and Living Area
  • Auto Motion Power Shades and Lambrequins
  • Auto Motion Power Shades for Windshield and Driver/Passenger Side Windows
  • Hardwood Window Sills
  • Hardwood Raised Panel Interior Passage Doors
  • Flush Handles on Swinging Bath Doors
  • Interior Assist Handle at Main Entry Door
  • Fitted Non-Quilted Bedspread with Accent Pillows
  • Safe Located in Bedroom Wardrobe
  • Waste Basket in Kitchen Base Under Sink
  • Maximized Shoe Storage Shelves Recessed in Rear of Wardrobe


Audio and Video

  • Samsung LED TV in Living and Bedroom Areas* (TV Sizes Vary Per Floorplan)
  • Samsung 43” 4K LED TV in Front Overhead
  • Samsung 50” 4K LED TV on Televator in Living Area*
  • Bose® 500 Subwoofer
  • Bose® 700 Sound Touch Sound Bar in Livingroom
  • Xite Dash Radio, 10” Dual Monitor with Nav-N-Go Navigation
  • Xite HD 360 Camera System with Predictive Grid Lines and Tri-View Rear Camera
  • Rearview Color Monitor System with Audio
  • Winegard Rayzar Automatic Digital TV Antenna
  • Satellite Dish Prep on Roof
  • Two Bedroom Radio Speakers
  • TV Jack and 110 Volt Recept in Door Side Exterior Storage Compartment
  • Cat 6 TV Cables
  • Infra Red Repeater System to Operate Audio/Visual Components
  • WiFi Ranger Tenton/Poplar LTE
  • 10 Bc Fire Extinguisher, Smoke Detector, Propane and Carbon Monoxide Detector
  • Remote Navigation Programming via SD Card


  • Sirius Satellite Radio Capability (Does not include monthly subscription)
  • Exterior Entertainment Center in Sidewall with Samsung 43” 4K LED TV and Soundbar
  • Exterior Entertainment Center in Storage Compartment with Samsung 43” 4K LED TV & Bose® Soundbar
  • Wifi Ranger Denali/Spruce Lte
  • Winegard Automatic Open Face Satellite Dish-For Dish HD & Bell HD TV
  • Winegard Automatic Open Face SWM Satellite Dish-for Direct TV Std/HD & In-Motion Direct TV Std, Dish Std/HD
  • Winegard Automatic Open Face Satellite Dish & Winegard In-Motion for Dish Network
  • Winegard Automatic Open Face Satellite Dish for Direct TV
  • Winegard In-Motion Dome Satellite Dish-for Dish Std/HD, Direct TV Std. & Bell Canada
  • Two-19” Skyworth TV/DVD Monitors at each Bunk*
  • Extra Monitor on Passenger Side
  • Rear Camera (2) Prep for Use with Stacker Trailer
  • Universal Toll Module

See us for a complete list of features and available options!

All standard features and specifications are subject to change.

All warranty info is typically reserved for new units and is subject to specific terms and conditions. See us for more details.

Due to the current environment, our features and options are subject to change due to material availability.


Newmar Logo

Newmar is a company built around the Christian faith, specifically the beginning of the Mennonite faith in 1525 under the guidance of Ulrich Zwingli, and the founding of the Amish fellowship under Jacob Amman in 1693.


At Newmar, we believe that a motor coach is more than just a vehicle, it’s a passport to countless hours of fun and a lifelong memories taken from quality time spent with family and friends.


For over 50 years, we’ve applied our principles to the creation of motor coaches that have allowed people all over the world to live the RV lifestyle. And we’ll continue to so for countless generations to come. It’s why we take pride in every rivet, weld, and mechanical function.