Door Gearboxes & Gearbox Locks

Repair and restore your multipoint locking systems with our premium selection of replacement door gearboxes. When a uPVC or composite door mechanism fails, you usually do not need to replace the entire expensive full-length locking strip. Simply swapping out the central gearbox lock is a highly cost-effective and straightforward fix that restores your door's security in minutes.

We stock a comprehensive range of replacement gearboxes from industry-leading security brands, including ERA and Yale Doormaster. Whether you need a standard replacement deadbolt gearbox, a hook follower, or a dual follower configuration, our selection covers the most common UK profiles. With standard backset sizes available (including 35mm and 45mm), you can easily match your existing hardware to secure your property.

Save money on complete lock replacements and get your home secured quickly with our reliable door gearbox components, available for next-day delivery or Click & Collect.

 

Frequently Asked Questions | FAQs

What is a door gearbox?

A door gearbox is the central component of a multipoint locking system, commonly found on uPVC, composite, and French doors. It houses the intricate mechanism that throws the locking hooks, rollers, and deadbolts when you lift the handle and turn the key. If your door handle is suddenly spinning freely, drooping, or the lock is jammed, replacing the internal gearbox lock is the standard, cost-effective repair.

How do I measure a replacement gearbox lock?

To ensure you buy the exact matching replacement gearbox lock, you must record two critical measurements from your old unit:

1. The PZ Centre: The distance from the absolute centre of the handle spindle hole to the centre of the rounded part of the Euro cylinder keyhole. (Standard UK sizes are usually 92mm).

2. The Backset: The horizontal distance from the front edge of the lock faceplate to the centre of the keyhole. (Common sizes are 35mm or 45mm).

Can you replace just the door gearbox?

Yes. In almost all cases where a multipoint door lock mechanically fails, only the central door gearbox has broken (usually a snapped internal spring or cam). Rather than buying a completely new, expensive multi-point strip, you can unscrew the broken gearbox from the metal strip and attach a replacement. Brands like Yale and ERA manufacture replacement gearboxes specifically designed to retrofit easily into existing setups.