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Under-RV storage can reclaim interior space for bulky, dirty or awkward gear, but it also places weight and hardware beneath the chassis. Lippert’s large double-bin system, part number 236558, is a substantial add-on that deserves careful measurement and a full payload check before ordering.
Key manufacturer specifications
- Overall dimensions: approximately 99.5 inches wide by 22.5 inches deep by 10.188 inches high.
- Two sliding bins, each approximately 19 by 48 by 9 inches.
- Rated for up to 100 pounds per bin, 200 pounds total.
- Keyed storage with rust-inhibitive coated steel components.
- Mounting hardware is not included.
- Manufacturer lists a one-year warranty.
Fit checks that matter most
- Chassis space: Measure the proposed span, depth and vertical envelope. Check tanks, plumbing, wiring, slide mechanisms, crossmembers, spare-tire hardware and suspension travel.
- Ground clearance: Account for driveway transitions, campsite crowns and departure angle. The lowest part of the installed system must remain safely protected.
- Structural attachment: Do not assume any thin floor or frame flange is a mounting point. Lippert notes that hardware is not included, so the correct fasteners and attachment method depend on the RV.
- Access: Confirm each tray can extend without hitting tires, steps, jacks, sewer fittings or campsite utilities.
- Loaded weight: Include the storage system itself, mounting hardware and everything placed in both bins when calculating cargo capacity.
Match part number 236558 and verify dimensions, included parts, seller, and current manufacturer specifications.
Payload and balance
A 200-pound bin rating is not permission to add 200 pounds to every RV. The coach’s cargo-carrying capacity, GVWR, axle ratings and tire ratings still control. Location matters too: weight added behind an axle can change axle loading and trailer tongue weight. Weigh the fully loaded RV or trailer by axle after installation, and never exceed the lowest applicable rating.
Installation approach
This is a job for someone who understands the specific chassis and can protect fuel, propane, electrical and plumbing systems. Dry-fit the assembly, verify travel paths and choose manufacturer-approved mounting points. Use corrosion-resistant, correctly rated hardware and torque it as specified. Recheck fasteners after the first trip and during routine maintenance.
Best uses
The long, shallow bins suit leveling blocks, hoses, outdoor mats, compact tools and other low-profile gear. Secure contents so they cannot shift. Keep sensitive electronics and absorbent materials away from road spray, and never store loose fuels or hazardous materials contrary to their labels or RV safety guidance.
Our take
Part 236558 can solve a real storage problem on a compatible rig, but it is not a universal accessory. The smart sequence is measure, confirm structure, calculate loaded weight, plan installation, then buy.
Primary source: Lippert part 236558 product page. Verify current specifications and fit guidance with Lippert before ordering.
Photo by Brina Blum on Unsplash.