2027 Keystone Montana3900RK

Keystone publishes three weights for the Montana 3900RK: a shipping weight of 17,085 lb, a carrying capacity of 2,320 lb and a hitch weight of 3,405 lb. Those are Keystone’s own terms, and this page keeps them. Keystone does not call the first figure dry or unloaded weight, does not say the hitch figure is measured dry, and publishes no GVWR for any Montana floorplan, so none of the three is renamed here and no loaded rating is worked out from them. The trailer’s own federal weight label, inside the door, is the document that carries its UVW, cargo capacity and GVWR.

Tank capacities are 77 gal fresh, 150 gal gray and 100 gal waste, as Keystone lists them. Fresh water weighs about 8.3 lb per US gallon, so a full fresh tank is roughly 639 lb on the road before anything else is loaded. The tire size Keystone lists is 215/75R17.5H; a fifth wheel puts its pin load into the truck bed, so it counts against the truck’s payload rather than its tow rating.

Against the 4 Montana floorplans profiled here, this one is the 4th by Keystone’s shipping weight, in a range from 15,915 lb (3500RD) to 17,085 lb (3900RK). Every figure in that comparison comes from the same Keystone page type for the same model year, so the comparison inside the series is like for like.

Every number on this page was read on 23 Oct 2026 from Keystone’s own floorplan page for the Montana 3900RK. That page carries no model year, so the year comes from the roster page that links it, which lists the Montana floorplans under the heading “2027 Floorplans”. Keystone notes that its website reflects the most recent production run and that features and specifications change during the year.

How the 3900RK differs from the other sixteen Montana floorplans. Most distinctive first. Each rank counts only the siblings that publish that field, and a figure most of them share is left out. Not every one of these pages covers the same model years as this one (2027); each figure is the one its own page prints, so a rank compares pages, not one model year.

• Shipping weight (Keystone’s term), 17,085 lb: heaviest of four; next is the 3800FL (16,750 lb).
• Carrying capacity (Keystone’s term), 2,320 lb: smallest of four; next is the 3800FL (2,740 lb).
• Length, 43 ft 10 in: longest of seventeen; next is the 3915TB (43 ft).
• Grey tank, 150 gal: largest of sixteen; next is the 3915TB (137 gal).
• Hitch weight as Keystone lists it, 3,405 lb: second-lightest of four, between the 3500RD (2,745 lb) and the 3600RO (3,410 lb).
• Hitch weight as a share of shipping weight, 19.9%: second-smallest of four, between the 3500RD (17.2%) and the 3600RO and 3800FL (20.8%).
• Fresh tank, 77 gal: largest of seventeen, level with the 3100RL, 3500RD and two others; next are the 3123RL, 3231CK and ten others (70 gal).
• Sleeping capacity, 6: shared with the 3500RD, 3761FL and three others; of seventeen, ten smaller and one larger, nearest the 3100RL, 3123RL and eight others (4) and the 3857BR (8).

Next to the 3800FL, the nearest lighter floorplan by shipping weight, the 3900RK is 335 lb heavier by shipping weight, has 420 lb less carrying capacity, has a hitch weight 85 lb lighter, is 1 ft 3 in longer, has a grey tank 50 gal larger and sleeps two more; the two publish the same exterior height and fresh tank.

Keystone lists 5 Montana floorplans for 2027. 4 have a complete Keystone figure set and no existing page here, and are profiled, from 15,915 lb to 17,085 lb shipping weight; the others are catalogued on this page with the reason against each. Keystone publishes shipping weight, carrying capacity and hitch weight for these trailers, and no GVWR.

Closest sibling: the Montana 3941FO, nearest on the published figures. It differs on 2 of the 3 fields both publish (this plan first): length 43 ft 10 in vs 42 ft 7 in; fresh tank 77 gal vs 70 gal. They match on sleeps.

All 17 Montana floorplans: Montana line hub.

8 of the 18 fields this catalogue tracks are published for the 3900RK. Not published: dry weight, GVWR, cargo capacity (CCC), exterior width, interior height, black tank, slide count, axle count, awning, air conditioning.

Sourcing rules: methodology.