2027 Forest River Riverstone38BMB

The Riverstone 38BMB leaves Forest River's factory at 17,186 lbs dry, with a published GVWR of 19,250 lbs and 2,064 lbs of cargo capacity between the two. Cargo capacity is 11% of the loaded rating, and Forest River's own definition is worth reading before you plan against it: cargo capacity is what remains for fresh water, gear, food, batteries and every dealer-installed accessory. Fresh water alone is 8.3 lb per gallon, so filling this trailer's 79-gallon fresh tank spends 656 lbs of that 2,064 lbs before anything else is loaded.

Pin weight is 3,250 lbs, which is 19% of the dry weight. That figure lands on the truck's rear axle and comes straight off its payload rating - not its towing rating, which is the number most often quoted and the wrong one for this decision. Pin weight rises as the trailer is loaded, and a fifth wheel loaded toward its cargo capacity will put substantially more than 3,250 lbs over the bed. Read the payload figure on your own door sticker rather than a brochure maximum for the model.

Tank capacities are 79 gallons fresh, 100 grey and 50 black, 150 gallons of waste capacity against 79 gallons of supply. The ratio is what governs how long the trailer can sit off hookups: waste capacity exceeds fresh, so the fresh tank is the binding constraint and refilling extends the stay. Forest River publishes these three figures per floorplan, and they are the factory's numbers rather than a segment average.

Against the rest of the Riverstone roster this is the 2nd of 10 floorplans by dry weight, in a line that runs from 16,511 lbs to 19,771 lbs. It sits in the lighter third of the line. Comparing floorplans inside one line is more reliable than comparing across brands, because every figure here comes from the same factory channel on the same day.

A useful way to read the pair of weights is to stop planning against the dry figure. Nobody tows a trailer at 17,186 lbs: that is the weight before water, batteries, propane, bedding, food, tools and anything the dealer bolted on. Load half the published cargo capacity, which is modest for a family trip, and this plan is already near 18,218 lbs on the road. Compare that number against the tow vehicle, not the dry weight, and leave margin on top of it - the published GVWR of 19,250 lbs is a limit rather than a target.

Every number above was captured twice from Forest River and checked against itself before it was published. The line listing and the individual floorplan page are two separate factory renderings of the same trailer, and this plan's 4 shared figures agree exactly on both. Dry weight plus cargo capacity also equals the published GVWR exactly, which is the arithmetic check this site runs on every profiled floorplan. Where a figure is missing from this page it is because Forest River does not publish it in this channel, not because it was hard to find - and the row says so rather than being quietly dropped.

Forest River publishes no floorplan description for this plan in the channel this page is built from - only the numeric specification block. Rather than describe a layout from the floorplan code, which would be a guess dressed as a fact, this page carries what the factory publishes and says where it stops. 38BMB is a Riverstone designation and this site does not decode it into a layout claim.

How the 38BMB differs from the other nine Riverstone 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.

• Cargo capacity, 2,064 lb: smallest of ten; next is the 39RKFB (2,464 lb).
• Cargo capacity as a share of GVWR, 10.7%: smallest of ten; next is the 39RKFB (13%).
• Length, 39 ft 7 in: shortest of ten; next is the 39RKFB (42 ft 1 in).
• Dry weight, 17,186 lb: second-lightest of ten, between the 39RKFB (16,511 lb) and the 420RE (18,065 lb).
• GVWR, 19,250 lb: second-lowest of ten, between the 39RKFB (18,975 lb) and the 442MC (23,845 lb).
• Pin weight, 3,250 lb: third-heaviest of nine, between the 420RE (3,240 lb) and the 421FK (3,635 lb).
• Pin weight as a share of dry weight, 18.9%: third-largest of nine, between the 39RKFB (18%) and the 421FK and 45FLE (19.3%).
• Black tank, 50 gal: shared with the 420RE, 42FSKG and 45FLE; of ten, two smaller and four larger, nearest the 421FK and 425FO (40 gal) and the 39RKFB, 442MC and 44DBL (80 gal).
• Grey tank, 100 gal: shared with the 420RE, 42FSKG and two others; of ten, three smaller and two larger, nearest the 39RKFB, 425FO and 442MC (80 gal) and the 421FK and 44DBL (120 gal).

Next to the 39RKFB (2026 page), the nearest lighter floorplan by dry weight, the 38BMB is 675 lb heavier by dry weight, has a GVWR 275 lb higher, has 400 lb less cargo capacity, has a pin weight 275 lb heavier, is 2 ft 6 in shorter, has a grey tank 20 gal larger and has a black tank 30 gal smaller; the two publish the same exterior height and fresh tank.

Next to the 420RE (2026 page), the nearest heavier floorplan by dry weight, the 38BMB is 879 lb lighter by dry weight, has a GVWR 4,750 lb lower, has 3,871 lb less cargo capacity, has a pin weight 10 lb heavier and is 5 ft 2 in shorter; the two publish the same exterior height, fresh tank, grey tank and black tank.

Ten 2027 Riverstone floorplans with a full factory record, read from Forest River on 22 Oct 2026. They run 16,121 to 19,771 lb dry on lengths of 39 feet 7 inches to 45 feet 3 inches, with hitch weights of 2,845 to 4,235 lb and cargo capacities of 2,064 to 5,629 lb. Forest River publishes a GVWR for all ten, from 18,950 to 24,000 lb, and dry weight plus cargo capacity equals it exactly on every one.

A full 79-gallon fresh tank is about 656 lb of water (water counts as cargo: 49 CFR 571.120 S10.4.2), 32% of the 38BMB’s 2,064 lb cargo capacity, leaving 1,408 lb. Across 10 Riverstone floorplans the water share runs 11% to 32%, and this plan’s is the highest. Nearest on that share: Riverstone 39RKFB at 27%. Your own unit’s figure is on the label inside its entry door (49 CFR 571.120 S10.4.3).

Closest sibling: the Riverstone 39RKFB, nearest on the published figures. It differs on 7 of the 8 fields both publish (this plan first): length 39 ft 7 in vs 42 ft 1 in; dry weight 17,186 lb vs 16,511 lb; GVWR 19,250 lb vs 18,975 lb; cargo capacity 2,064 lb vs 2,464 lb; hitch weight 3,250 lb vs 2,975 lb; grey tank 100 gal vs 80 gal; black tank 50 gal vs 80 gal. They match on fresh tank.

Either side of it by GVWR: Riverstone 39RKFB is 275 lb lighter (18,975 lb GVWR); Riverstone 442MC is 4,595 lb heavier (23,845 lb GVWR).

All 10 Riverstone floorplans: Riverstone line hub.

Against the 38BMB: the Influence 3804DS is 250 lb lighter and 3 ft longer; the Momentum 344M is 250 lb lighter; the North Point 375TBDB is 250 lb lighter and 2 ft longer.

11 of the 18 fields this catalogue tracks are published for the 38BMB. Not published: interior height, sleeps, slide count, axle count, tire specification, refrigerator, air conditioning.

Sourcing rules: methodology.