2026 Keystone Montana3901RK

The 3901RK is built for living aboard. A U-shaped raised kitchen commands the rear wall, a mid-coach living room with a 50-inch Smart TV and a convenient half bath sits just inside the door, and a sliding barn door opens to a front master suite with a king bed, dual-sink full bath, a 48-by-30 shower and a walk-in wardrobe with washer/dryer prep. Five slides open the interior to near-residential proportions, and the front basement storage is oversized with slam-latch baggage doors.

It is a heavy, long coach. RVUSA lists a 42-foot-4 length and five slides; the published dry weight is 14,755 pounds against an 18,000-pound GVWR and a 3,245-pound payload — figures that are internally consistent (dry plus payload equals the rating). One source (Camping World) lists a lighter 16,800-pound GVWR and a 42-foot-2 length; the factory-consistent 18,000-pound figures are used here and the discrepancy is noted. An 18-cubic-foot residential refrigerator, a 24-inch range, a JBL three-zone stereo and a La-Z-Boy hide-a-bed in its own slide round out the interior.

At an MSRP of $133,778 it is the full-timer’s rear-kitchen plan in the luxury line — a coach for a couple who cooks seriously and lives aboard, and one that needs a one-ton truck, often a dually, to tow safely loaded.

Montana is Keystone's flagship luxury fifth wheel and the best-selling luxury fifth wheel in North America. The line runs to fifteen floorplans for 2026; the six highest-demand layouts are profiled here in full, and the rest — along with the lighter, lower-profile Montana High Country sub-line — are catalogued on the line hub. The 3901RK on this page is highlighted; each other profiled plan links to its own page.

This floorplan carries its water comfortably. A full 70-gallon fresh tank is roughly 18% of the 3,245-pound cargo capacity, leaving the 3901RK with a usable gear budget even when you tow full.

No dry pin weight is published for this floorplan by any source this catalog accepts, so the hitch-share arithmetic is not shown here and the tow block on this page omits it. The figure exists on the trailer’s own weight sticker; a scale ticket taken with the trailer hitched is the reliable way to get it, and it is worth having before you buy rather than after.

Nothing above changes the ceiling. Loaded to its 18,000-pound GVWR the 3901RK is towing 3,245 pounds more than its 14,755-pound dry figure, and that is the number your vehicle has to be rated for — not the brochure weight.

Tank balance is generous here: 70 gallons of fresh against 88 grey and 88 black, so waste capacity keeps pace with supply and the fresh tank is the constraint that ends a dry stay.

Ranked by GVWR, the 3901RK sits 11 of 13 in the Montana line: 18,000 pounds against a line that runs from 16,480 to 18,000 pounds. That position is the useful thing to know, because the plans immediately either side of it are the real alternatives.

Either side of it in the same line: Montana 3857BR matches it exactly at 18,000 lb GVWR; and Montana 3915TB matches it exactly at 18,000 lb GVWR.

7 other Montana plans share this floorplan’s 18,000 lb GVWR, so the ranking above separates plans that tow to the same ceiling. On a shared chassis the figure that actually differs between them is cargo capacity and where the weight sits, not the rating.

Against the 3901RK: the Cedar Creek 381MUD is 1 ft longer and sleeps 4 more; the Influence 3003RL is 7 ft shorter; the Paradigm 375RD sleeps 1 more. Those are differences in the published numbers only — what they cost, how they are built and how they live are separate questions each of those pages answers on its own terms.

Those are the nearest fifth wheels from other lines by weight — one per line, picked by proximity on that figure and nothing else. They are listed so the same tow vehicle can be checked against real alternatives, not because they are equivalent inside; layout, build and price diverge sharply across that group.

For scale, the Montana floorplans profiled here run 12,881 to 15,644 pounds dry and 35 to 43 feet of exterior length across 13 plans. Where a floorplan falls in that spread usually says more about which vehicle can tow it, and which site it fits, than the layout name does.

Every profiled floorplan in this line, with the full weight table, is on the Montana line hub.

This catalog tracks 18 specification fields per floorplan. Named sources publish 15 of them for the 3901RK. The rest are not shown, because the alternative is reading a figure across from a sibling floorplan or from what the segment usually does — and a number nobody published is worth less than an admitted gap.

Not published for this floorplan: dry hitch weight, tire specification, awning. If you find one of these in a manufacturer document for this plan, it belongs on this page.

The completeness figure at the foot of this page (94%) measures the same thing on the full field set: it is a measurement of how much this floorplan’s manufacturer publishes, not of how much research went into the page.

Values on this page carrying an asterisk were derived by arithmetic from published figures, or come from a single source, rather than being printed directly by the manufacturer. The flag travels with the number into the downloadable spec sheet.

How every figure here was sourced and checked is set out on the methodology page.