CamperHardlyKnowHer

Newmar Mountain Aire 4018

Class Abuilt 2014–19Better build tierPatient search on the used market
WHAT ONE COSTS
—price not published

The maker never published an MSRP for this floorplan. Unknown is not cheap — treat any asking price against comparable models, not against zero.

THE SPECS
Length40.8 ft
Height (incl. A/C)13.2 ft
Width8.5 ft
Interior height6.9 ft
GVWR54,000 lb
Dry weight43,500 lb
Sleeps5
Fresh water105 gal
Grey water65 gal
Black water45 gal
Fuel150 gal

A missing row means the maker never published that figure — unknown, not zero.

WHERE PEOPLE SLEEP
  • 1× master bedroom bed(Permanent)—
  • 1× convertible dinette(Convertible)—
  • 1× sofa sleeper(Convertible)—
HOW IT'S BUILT — 4/5
WallsLaminated fiberglass
FrameSteel
RoofWalk-on
UnderbellyEnclosed

Newmar (Better tier): Newmar Mountain Aire

YEAR BY YEAR — WHAT CHANGED
YEARSGVWRDRYMSRP
2014–1544,600 lb36,400 lb—
2016–1954,000 lb43,500 lb—
  • 2014Introduced at 40'9", 44,600 lb GVWR with the 450 hp Cummins ISL
  • 2017Moved to the 54,000 lb Spartan K2 tag chassis with the 500 hp ISX
  • 2020Dropped
FINDING ONE

Patient search — weeks of watching, and probably some travel. Estimated from build volume and production span — not a count of live listings.

THE READ

Six model years - the 40-foot Mountain Aire that survived the jump from the 450 hp ISL to the 500 hp ISX.

OTHER MOUNTAIN AIRE FLOORPLANS
3823 · 54,000 lb · sleeps 53825 · 54,000 lb · sleeps 44002 · 54,000 lb · sleeps 54118 · 54,000 lb · sleeps 54360 · 44,600 lb · sleeps 54361 · 44,600 lb · sleeps 54364 · 44,600 lb · sleeps 54369 · 44,600 lb · sleeps 54372 · 44,600 lb · sleeps 54501 · 53,000 lb · sleeps 54503 · 53,000 lb · sleeps 54513 · 54,000 lb · sleeps 54519 · 54,000 lb · sleeps 54521 · 54,000 lb · sleeps 5the whole line →
Is the 4018 your #1 — or just a spec sheet?

These are the facts. Whether it beats the other six thousand rigs for you depends on what you care about — set your priorities as sliders and watch the whole market re-rank around them. Nothing gets hidden, everything gets explained.

Rank it against your setup →

Data compiled from dealer and aggregator listings, retrieved 2026-07.