How To Protect Your Cargo Trailer From Being Broken Into - Shipping Container Lock Box Solution

Do you own a cargo trailer? Are you looking for a secure way to lock it up? We have our high-security lockbox which is used for shipping containers, but it also works on enclosed trailers.

No locking system will ever be thief-free, but the more difficult you make your trailer to break into, the less likely someone will target it.

This lock box is designed around the 80mm lock to completely encase the lock so bolt cutters or angle grinders cannot get access.

Check out RJB Contracting Website here: http://rjbcontracting.ca/

List of tools required:
Marker
Drill
7/32 drill bit
31/64 drill bit
5/8s Flat Wrench or Socket

What Comes With This Lock Box:
Lock Box
Carriage Bolts (Insulated and Non-Insulated)
Flat Washers
Nylock Nuts
Back Washer Plates
Lock Receiver
Shackle Lock (ONLY in Lock & Lock Box Combo)

Note: The shackle locks come Keyed Alike or Keyed Different.




Purchase Container Modification World Products Featured in The Video

Installing a High-Security Lock Box on a Cargo Trailer or Shipping Container

In this walkthrough, Riley Blutterth of RJB Contracting shares a real-world experience that led to upgrading his cargo trailer security. After a recent break-in where tools were stolen despite having a lock installed, Riley decided it was time for a stronger solution.

The result was installing a high-security lock box system designed for shipping containers but equally effective on cargo trailers.

Why Upgrade Your Lock System?

Traditional locks often leave the shackle partially exposed. Even small gaps can allow bolt cutters or pry bars enough access to compromise the lock.

In Riley’s case, his previous setup had limited shackle exposure, but it was still vulnerable. The upgrade focused on eliminating those weaknesses by enclosing the lock inside a protective steel housing.

Lock Box Design Features

This lock box is engineered with security in mind.

Key features include:

• A laser-cut profile that clears typical rubber door seals

• Asymmetrical depth to match container-style doors

• Minimal internal space around the lock shackle

• Compatibility with an 80mm shackle lock

The reduced clearance around the shackle prevents bolt cutters, pry bars, and angle grinders from gaining access.

The design also protects latch components from being twisted or cut.

Hardware Included

The system comes with:

• Grade 5 carriage bolts in 3-inch and 4.5-inch lengths

• Large washer plates

• Grade 8 flat washers

• 7/16-inch nylock nuts

The washer plates can double as marking templates during installation. The 4.5-inch bolts are useful for thicker insulated doors and can be trimmed if necessary.

An 80mm shackle lock is required. A smaller 60mm lock will not fit properly within the enclosure.

Installation Process Overview

Step 1: Position and Mark

For cargo trailers without rubber door seals, a second washer plate can be used to simulate seal thickness during placement.

Careful leveling and measuring are essential before drilling. Misalignment can lead to improper fit or uneven pressure on the door.

Step 2: Drill Pilot Holes

Start with pilot holes to ensure accurate placement. Then enlarge the holes using a 31/64-inch drill bit to accommodate 7/16-inch carriage bolts.

Step 3: Insert Carriage Bolts

Carriage bolts fit into laser-cut square slots in the lock box. These square cutouts prevent the bolt heads from spinning while tightening.

Insert bolts through the door and secure them with grade 8 flat washers and nylock nuts.

Step 4: Tighten Evenly

Tighten bolts evenly to avoid uneven pressure or door distortion. The nylock nuts help prevent loosening over time.

Security Advantages

This lock box significantly increases resistance to forced entry.

Benefits include:

• Eliminates exposed shackle access

• Prevents bolt cutter engagement

• Reduces pry-bar leverage points

• Shields latch components

• Makes grinder access extremely difficult

The enclosed design leaves virtually no space for tools to attack the lock.

Psychological Deterrence

A simple addition can further improve security: a 24-hour warning security sticker.

Even if no alarm is installed, visible warning labels can act as a psychological deterrent. Many thieves look for easy targets. When a trailer appears reinforced and monitored, they are more likely to move on.

Why Proper Installation Matters

Precise alignment and careful drilling are critical.

If the box is mounted crooked or too loosely, it can compromise both function and security. Taking time to measure properly ensures the lock box performs as designed.

Though installation is straightforward, it should not be rushed.

Final Thoughts

Upgrading from a traditional exposed lock to a fully enclosed lock box is a major step forward in cargo trailer and container security.

By minimizing exposed shackle space and protecting latch components, this system dramatically reduces vulnerability to bolt cutters, pry bars, and grinders.

When combined with proper installation and visual deterrents, a lock box like this can make your trailer or container far less attractive to thieves.