Never settle.

You’ve earned the right to explore new places and meet new people. We’re here to make sure your journey is safe, smooth, and always first class. As the industry leader in chassis-centric innovations, improving the safety culture is core to Spartan RV Chassis. That’s why Newmar has partnered with us to raise the bar on safety on their coaches.

The Newmar Mountain Aire is available on a 38′, 40′ or 45′ Spartan RV Chassis K3 525 chassis. Designed, engineered, and made in America with the finest components creating a premier foundation for the most discerning RV makers and owners.

Spartan RV Chassis makes the only chassis built exclusively for motorhomes. We didn’t take the easy route and modify a truck chassis for our partners at Newmar. We knew they wanted an unmatched ride that was as smooth and quiet as it was invigorating and well-appointed. So, we built them the unique K3 525 chassis from the ground up. The highest-quality materials provide reliability and dependability, along with nationwide service, and the best warranty in the business.

Motorhomes riding on a Spartan RV chassis are built with care to stay on the road for a good long time.

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Premium Features

  • Comfort Drive ™ steering assist system w/ variable driver’s effort control feature
  • Independent front suspension
  • Electronic suspension control system with self-leveling feature including air compressor for extended stays
  • Automatic heated moisture ejectors with color-coded lanyards
  • Side-mounted service center
  • Connected Coach® 12.3” glare-free digital dash display
  • Passive steer tag axle
  • Headlamps with auto on/off feature
  • 3-stage engine compression brake
  • 15,000 lb towing capacity
  • Tri-Pod Steering Wheel with leather finish, phone, and media controls
  • Spartan Passive Keyless Start
  • Suspended adjustable pedals
  • Air disc brakes at all wheel positions
  • Available CURT Spectrum™ trailer brake control


38′, 41′ or 45′

Peak HP

500 hp @ 1,900 rpm


41’ 258” + 48 tag
45’ 294” + 48 tag

Towing Capacity

15,000 lb



Safety Innovations

Spartan RV Chassis Advanced Protection System – Mountain Aire

  • Automatic Traction Control (ATC)
  • Adaptive Cruise Control (ACC)
  • Electronic Stability Control (ESC)
  • Collision Mitigation System with Adaptive Cruise Control
  • Mobileye® visual & audible lane departure warning
  • Tire Pressure Monitoring System (TPMS)
  • Spartan RV Chassis Safe Haul™ (The industry’s premier factory-chassis integrated air supply for tow vehicle brake systems.)



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Service Manuals

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Alternative Fuels


Ford Transit

RAM ProMaster