Reese Fifth-Wheel Mounting Rails: Inboard vs Outboard Brackets

Fifth-wheel mounting rails sit inside the pickup bed and connect to brackets attached to the truck frame. Reese inboard and outboard bracket kits use different rail layouts. If your brackets or rails are missing, match the original mounting system before buying replacements. A bracket-only kit is not the same product as a complete rails-and-brackets installation package.

What's the difference between inboard and outboard?

Inboard mounting: The brackets support a conventional rail arrangement with mounting bolts farther inboard, where access can be more confined beneath the bed. An inboard custom-bracket set must be paired with the rails specified for that bracket system.

Outboard mounting: The rail bolts sit farther out toward the pickup-bed sides. This layout generally allows easier access to the bracket fasteners, but it requires outboard-spacing rails rather than standard inboard rails. Reese's outboard rail number 30153 is the specified companion for the 56034 Ford F-150 brackets; it is not part of the bracket-only package.

Both mount the trailer hitch to the truck, but the rail hole patterns, cross-bed layout and bracket hardware must match. Do not mix parts from different Reese rail systems just because the same fifth-wheel hitch can be installed in both.

Compare Reese bracket part numbers

See the bracket assemblies

Reese 50087: Ford F-150, inboard brackets

Ford F-150 2015–2020, excluding Raptor; rails sold separately.

View Reese 50087

Reese 56034: Ford F-150, outboard brackets

Manufacturer's Ford F-150 application; requires Reese 30153 outboard rails; excludes Raptor and ride-height sensor trucks.

View Reese 56034

Reese 50054: Ram 2500 brackets

Ram 2500 application; verify truck year, bed and frame before ordering.

View Reese 50054

Reese 50066: Silverado / Sierra HD brackets

GM heavy-duty truck application; inspect manufacturer application chart.

View Reese 50066

Reese 56001: GM heavy-duty outboard brackets

Chevrolet / GMC application; select the matching outboard rails.

View Reese 56001

Reese 56018: Ram 1500 new-body outboard brackets

New-body Ram 1500 application, separate from classic-body trucks; match rails and manufacturer fitment.

View Reese 56018

Ford F-150: 50087 versus 56034

Reese 50087 is the custom inboard bracket set for the specified F-150 applications. The bracket-only kit does not include the in-bed rails. By contrast, 56034 uses the outboard layout with Reese 30153 wide-spaced rails, also purchased separately. Manufacturer fitment for 56034 excludes Raptor models and trucks with ride-height sensors.

50087 is listed for 2015–2020 F-150 models. For 56034, check Reese's current application chart and installation instructions for the exact truck year and configuration before ordering.

Frame brackets, rails and mounting hardware

1. Truck-frame brackets: These bolt to specific frame locations and position the supports below the pickup bed. The hole locations and left/right pieces are vehicle-specific.
2. In-bed rails: These provide the standardized mounting connection for compatible fifth-wheel hitch legs. Standard and outboard rail bolt locations differ.
3. Bed and frame fasteners: Use the specified bolts, spacers, washers and nuts for the particular bracket kit. Do not substitute bolt lengths or drill new locations by eye.
4. Hitch retaining pins: These secure compatible hitch legs to the rails. For a replacement set, see Reese 58467 outboard rail pins and clips; confirm pin dimensions and intended hitch system.

Before installing a fifth-wheel rail kit

Check the manufacturer's application chart for your truck's model year, model generation, cab, bed length, drivetrain and frame equipment. Confirm clearance around brake and fuel lines, wiring, exhaust, suspension and any sensors before drilling or tightening fasteners. Follow the instruction sheet for the correct rail distance and tightening sequence; rail-spacing dimensions are not interchangeable between every kit.

Even with the correct bracket kit, the hitch and the truck must be rated for the loaded trailer's weight and pin load. For information on hitch heads, centre sections and legs, see our Reese M5 fifth-wheel component guide.