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Monaco Diplomat 40PRQ

Class Abuilt 2005–05Mixed build tierScarce on the used market
WHAT ONE COSTS
$126,700est. used (2005, 21 yr old; from 15 priced floorplans of this line)
THE SPECS
Length40.5 ft
Height (incl. A/C)12.3 ft
Width8.4 ft
Interior height6.8 ft
GVWR33,000 lb
Dry weightnot published
Sleeps6
Fresh water100 gal
Grey water62 gal
Black water40 gal
Fuel100 gal
Engine / chassisCummins ISL 400 hp 8.9L / Roadmaster RR8R, Allison 3000 MH 6-speed
GeneratorOnan 8.0 kW Quiet Diesel

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

WHERE PEOPLE SLEEP
  • 1× Master queen bed with solid-surface nightstands(Permanent)60×80
  • 1× Roadside sofa bed(Convertible)—
  • 1× Curbside sofa bed(Convertible)—
HOW IT'S BUILT: 4/5
WallsLaminated fiberglass
FrameAluminum
RoofWalk-on
UnderbellyEnclosed

Monaco (Mixed tier): Monaco Coach Corp (2005-2009), Navistar RV (2010-2013), REV Recreation Group (2014-2017)

YEAR BY YEAR: WHAT CHANGED
  • 2005Introduced
FINDING ONE

Scarce: months of watching; be ready to fly and drive it home. Why: only one model year; 21 years out of production. Estimated from build volume and production span, not a count of live listings.

OUR TAKE

Quad-slide 40-footer with twin sofas and a swing-out TV — the entertaining plan.

OTHER DIPLOMAT FLOORPLANS
36SKT · 33,000 lb · sleeps 438PDD · 33,000 lb · sleeps 438PDQ · 33,000 lb · sleeps 640DST · 33,000 lb · sleeps 440PAQ · 33,000 lb · sleeps 440PDQ · 36,000 lb · sleeps 841PDQ · 36,000 lb · sleeps 841SKQ · 36,000 lb · sleeps 843D · 44,600 lb · sleeps 643DF · 44,600 lb · sleeps 843DFT · 43,000 lb · sleeps 843G · 44,600 lb · sleeps 643P · 44,600 lb · sleeps 643PDQ · 43,000 lb · sleeps 8the whole line →
Find one for sale

Live listings for the 40PRQ on the big marketplaces. Each search opens pre-filled with this exact floorplan:

RV Trader ↗Camping World ↗FB Marketplace ↗Google ↗

Inventory varies by site and day. Slim pickings? search the whole Diplomat line ↗

Is the 40PRQ 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, switch on your hard limits, and watch the whole market re-rank around them. Every exclusion explained, every margin shown.

See where it ranks for you →

Data compiled from manufacturer spec sheets, retrieved 2026-07.