Home » Truck & Trailer Solutions » Truck & Trailer Parts
Door locks are mechanical systems used to securely close, lock, and seal the rear or side doors of a truck or trailer. They ensure that the doors remain tightly closed at all times during transport, preventing accidental opening, loss of cargo, or unauthorized access.

They are commonly used on:
- Dry freight trucks & trailers.
- Refrigerated trucks & trailers.
- Wing trucks & trailers.
- Curtain side trailers & trailers.




The system usually includes:
- Vertical locking rods (running from top to bottom of the door).
- A central handle (cam or lever type).
- Cam keepers / retainers (mounted on the door frame to hold the rods).
- Rod guides and door hinges.
- Seals to ensure weather-tightness.
Materials for Door Locking Gear
The materials depend on vehicle type, weight requirements, and corrosion resistance needs.
| Component | Common Materials | Notes |
|---|---|---|
| Locking Rods | Stainless steel, galvanized steel | Stainless for high corrosion resistance |
| Handle Assembly | Carbon steel, stainless steel, aluminum | Often zinc-plated for anti-rust |
| Cam & Keeper | Steel or ductile iron | Surface hardened for durability |
| Rod Guides | Nylon, rubber, or steel | Reduces vibration and friction |
| Fasteners | Stainless steel | Corrosion-resistant |
| Finish | Polished, hot-dip galvanized | Improves weather resistance and longevity |
Door Locking Gear Design Types
| Design Type | Description |
|---|---|
| Standard Cam-Type Locking Gear | Vertical rods lock into upper/lower retainers using cams and keepers; handle rotates to engage lock. |
| Recessed Door Locking Gear | Handle and cam sit flush with door surface for safety and aesthetics. |
| 3-Point Locking System | Central handle operates rods locking in three directions (top, bottom, and side). |
