SALE PENDING

2007 Newmar Mountain Aire 4521 45 Luxury Diesel Pusher Excellent Condition

This beautifully maintained 2007 Newmar Mountain Aire 4521 is a high end, 45-foot Class A diesel pusher built on the Spartan K2 chassis and powered by the legendary 450 HP Cummins ISM paired with a 6speed Allison automatic transmission. If you're looking for a powerful, reliable, and exceptionally well cared for coach, this one stands out.

Coach Highlights

• 90,750 miles

• Spartan K2 chassis

• 450 HP Cummins ISM engine

• Allison 6speed automatic transmission

• 15,000 lb towing capacity

• Four slide-outs

• Aqua Hot hydronic heat & endless hot water (electric + diesel)

Ownership & Storage

• Privately owned for 8 years

• Always stored in a climate-controlled 60×48 building

• No smoking, no pets very clean interior

Generator & Power

• Onan 10kW diesel generator 1,680 hours

• Provides reliable power for boondocking and travel

Tires & Batteries (Major Updates)

• Front tire codes: 4124

• All other tires replaced on 2/23/2026 Tire Codes: 2525

• House batteries replaced on 2/16/2026

These upgrades alone save the next owner thousands of dollars.

Interior Comfort

• Spacious quad slide layout

• Quality Newmar craftsmanship throughout

• Clean, odor free interior

• Aqua-Hot system provides quiet, even heat

• Comfortable living area, fully equipped kitchen, and well-designed bedroom suite

Why This Mountain Aire is a Great Buy

This coach combines top tier build quality, a highly desirable powertrain, and a long list of recent maintenance updates. The indoor storage, no smoke/no pet history, and mechanical care make it far above average for its age. If you're searching for a well-maintained Mountain Aire 4521 ready for cross country travel, this one deserves your attention.