HD Ramps Tool box

HD Ramps Underbody Trailer Tool Box Guide

An underbody box puts chains, binders and straps under the deck instead of in the cab or headache rack. These boxes are built for flatbed and step deck trailers and made from high-strength aluminum, which does not rust through from road salt and spray.

Pick a Box Size

• 60" x 18" x 18" — Rated 400 lb and weighs 73 lb empty. Sized for standard underbody clearance on a flatbed or step deck.
• 60" x 18" x 24" — More room than the 18" x 18" box at the same 60" width.
• 60" x 24" x 24" — The largest box in the range, for a full securement kit.

The 60" width lets chains lie flat, so they come out one at a time instead of in a knot. Every box has a lockable door that takes a padlock (padlock not included).

Mounting Brackets

Each box mounts on a bracket set sized to it: 18" x 18", 18" x 24" or 24" x 24". The brackets are high-strength aluminum, and the 18" x 18" set has a 2-1/2" profile that keeps the box tight to the frame. No shimming or extra holes needed.

Door Upgrades

• Polished aluminum doors — For 60" W x 18" H and 60" W x 24" H cabinets.
• Stainless steel doors — For the same two cabinet sizes. Stainless stays bright in road salt without polishing.

Each door is a direct-fit replacement for the door already on the cabinet. No new box and no fabrication.

Trailer Tool Box FAQ

Which mounting bracket fits my box?

Match the bracket to the box: the 18" x 18" brackets are made for the 60" x 18" x 18" cabinet, and the 18" x 24" and 24" x 24" sets follow the same pattern.

Will a flatbed trailer tool box fit a step deck?

Yes. The boxes are made for both flatbed and step deck trailers. Check the clearance under your deck against the box height before you order.

Store ramps on the same trailer with brackets from ramp accessories, or see the full HD Ramps range. Questions about fit? Contact us or call 855-559-5589.