Underfloor capacity is the hardest kind to add, and it is exactly what the Ronco Plastics B483 provides: 92 gallons in a 53 x 31 x 14.25 inch slab that rides between chassis rails or beneath a cabin sole. The proportions are the product.
The B483 is a dual-role B-series molding. Fresh water fittings make it a potable tank, with food-contact polyethylene appropriate for drinking water; waste fittings make it a broad, shallow gray or black holding tank. Ronco installs your fittings per order, spin-welded or threaded, and in a 14.25 inch tall tank that precision decides whether your dip tube, vent, and sender all clear each other, so mark the drawing carefully.
Weight planning: about 767 lb of water at 8.34 lb per gallon when full, distributed across the wide footprint, plus 118 lb of tank. Print the dimensioned drawing below, verify rail spacing and depth, then commit the port layout in the on-page fitting planner.
Made in Tustin, California by Ronco Plastics, molding since 1974. The RV water tank line holds smaller underfloor formats, the RV holding tanks cover the waste side, and the freight cost estimator prices your lane. OneSource Plastics is an authorized Ronco Plastics dealer.
Technical drawing: download the Ronco Plastics B483 dimensional drawing - print it to plan your install and mark exactly where you want fittings located; Ronco installs spin-weld or threaded fittings to your marked spec.
