MB Logo

Door Gearbox

A Door Gearbox is the most frequently used component of the lock and is, therefore, the most likely to fail. When the central mechanism of a Multipoint Door Lock becomes faulty, it’s crucial to replace it promptly to ensure the lock continues to function properly. Instead of replacing the entire multipoint lock, which can be expensive and time-consuming, replacing the Gearbox is a much cheaper and effective solution. Replacement Door Gearbox is available from MB DIY. Offering many brands such as ERA, Mila, and Lockmaster, which are suitable for uPVC and Composite Doors.


Keep in mind that these items are limited to the lock’s core mechanism. If you are unable to identify the appropriate Gearbox for your door, please contact a member of our sales staff who will gladly assist you.

Expert Techniques for Replacing a Door Gearbox

When searching for a new Door Gearbox, it’s important to consider several key factors to ensure you get the right one. Firstly, the brand is crucial and should be indicated on the metal strip inside the door.

The next factor to consider is the lock size, typically either 35/92 or 45/92. The first measurement, the backset, represents the distance from the front of the lock to the centre of the spindle. The second measurement, the PZ Centre measurement, is the distance between the keyhole and the spindle’s centre.

Finally, the type of spindle is a crucial aspect to keep in mind. If the door handle is positioned identically inside and outside, then the door has a single spindle, which includes a spring to keep the handle in place. On the other hand, if the handle is at different heights inside and out, the door requires a Dual Spindle Gearbox or split spindle gearbox.

The Ultimate Step-by-Step Guide to Door Gearbox Replacement

Replacing a door gearbox can seem like a daunting task, but with the right tools it is a relatively simple process to complete.

Step 1: Unscrew the door handle from the door. You can use either a screwdriver or a cordless drill to do this.

Step 2: Carefully remove the door cylinder (sometimes known as a barrel) and place it aside. This can be removed by locating a screw which lines up with the door cylinder.

Step 3: Detach the lock strip from the door: Unscrew the Philips screws but leave the Torx screws in place at this point. Removing the Phillips screws will remove the door strip from the door.

Step 4: Once the lock is removed, take out the Torx screws from the Gearbox and make note of the position these screws came out of, then gently remove the gearbox from the bar.

Step 5: Align the new Gearbox with the locking points on the bar and secure it back in place using the screws that were previously removed in the same order.

Step 6: Test the locking mechanism by using both the handle and the cylinder. Ensure the handle engages the locking points and ensure the door cylinder can both lock and unlock the door. Make sure the mechanism is properly aligned before reinstalling it on the door.

Step 7: Reinstall the lock strip onto the door using the Phillips screws and reattach all hardware, including the door handle and cylinder.

You’re all set!

It’s best to always test your new gearbox by repeatedly opening and shutting the door to ensure it is working properly.

The Door Gearbox Brand: Your Most Crucial Step

A Door Gearbox offers a range of solutions, and there are several brands on the market from which to pick. From ERA Gearbox through Lockmaster Gearbox to GU Fero Gearbox, and Fullex Gearbox, MB DIY provides them all. Each brand has its own strengths and weaknesses, and they are available in a number of backset sizes, including 28mm, 35mm, and 45mm. By considering the features and capabilities of each brand, you can choose the one that will provide you with the best performance and the most value for your money.

ERA Gearbox

If you are looking for a brand that offers a wide range of products and has a good reputation for quality, ERA Gearbox might be a good choice. The ERA Gearbox brand has been in business for many years and has a wide range of gearboxes for various applications. Additionally, ERA Gearbox products are known for their durability and reliability, making them a popular choice for many customers.

Lockmaster Gearbox

Lockmaster Gearbox is another reputable brand that offers a range of high-quality gearboxes. This brand is known for its innovative design, advanced technology, and superior performance. If you are looking for a gearbox that is both efficient and long-lasting, Lockmaster Gearbox might be the right choice for you.

GU Fero Gearbox

GU Fero Gearbox is a newer brand that has quickly become popular due to its affordability and reliability. This brand offers a range of gearboxes at competitive prices, making it an attractive option for customers who are looking for an affordable yet high-quality solution. If you have a tight budget but still want a gearbox that performs well, GU Fero Gearbox might be the right choice for you.

Fullex Gearbox

Fullex Gearbox is another brand that offers a range of gearboxes for various applications. This brand is known for its innovation, high-quality materials, and exceptional performance. If you are looking for a gearbox that is both reliable and efficient, Fullex Gearbox might be the right choice for you.

Guide to Selecting Gearboxes for uPVC and Composite Doors

While both a uPVC Gearbox replacement and a Composite Door Gearbox Replacement serve the same purpose, the doors are made of different material and composition. uPVC Gearbox replacement is un-plasticized (which is what the letter u represents) and is also known as solid plastic. It is commonly used in the construction of windows and doors. Composite doors, on the other hand, are made from a combination of materials, including wood, fiberglass, and PVC. This combination provides a high level of durability and resistance to weather.

In addition to their security benefits, a uPVC Gearbox replacement is also easily maintained and requires hardly any upkeep. Unlike wooden doors, which can warp, rot, or become damaged over time, uPVC Gearbox replacement is designed to be weather-resistant and require very little maintenance. This can help save time and money, as well as ensure that the door continues to function properly for many years to come.

Discover the Benefits: The Top Reasons to Get a Door Gearbox Replacement

A door gearbox is a cost-effective and practical solution for enhancing the security of a property. With its durability, resistance to weather, and low maintenance requirements, a door gearbox can provide peace of mind and help to keep intruders out. Whether you are a home or a business owner, a door gearbox is a smart investment that can keep your property secure for many years to come.

Another benefit of replacing a worn-out door gearbox is its ability to enhance the security of a property. The gearbox is designed to be strong and durable, making it difficult to break or tamper with. However, once the gearbox begins to fail, it becomes a security hazard and should be replaced immediately.

In conclusion, by considering the brand, lock size, and type of spindle, you can ensure that you have selected the correct Door Gearbox for your property. At MB DIY, we offer uPVC Gearbox Replacement brands such as ERA Gearbox, Lockmaster Gearbox,

If you are unable to identify the appropriate Gearbox for your door, please contact a member of our sales staff who will gladly assist you.


MB Logo
Monday 7:30 AM to 5:00 PM
Tuesday 7:30 AM to 5:00 PM
Wednesday 7:30 AM to 5:00 PM
Thursday 7:30 AM to 5:00 PM
Friday 7:30 AM to 5:00 PM
Saturday 8:00 AM to 4:00 PM
Sunday Closed
Bank Holidays Closed

We use cookies to personalise content and ads, to provide social media features and to analyse our traffic. We also share information about your use of our site with our social media, advertising and analytics partners who may combine it with other information that you’ve provided to them or that they’ve collected from your use of their services. By using this website you agree to our collection of such information. Learn More

Contact Form

We endeavour to respond to all enquiries within 4-6 hours (during working hours) however on some occasions this may take a little longer.

Need an Answer!

Fullex Crimebeater Replacement Centre Case 35&45/62&92 Dual Spindle

Due to length & size restrictions with our delivery partners, we are currently only able to deliver certain items to the following postal areas:

  • All TS postcodes
  • All NE Postcodes
  • All DL Postcodes
  • All DH Postcodes
  • All SR Postcodes

We are looking into increasing our postcode range gradually with our own fleet of vehicles.
Should you not want to opt for a delivery service, please be aware Click and Collect is still available on all of our items.

We aim to despatch all of our orders within 24-48 hours of order confirmation, during peak times or bank holidays this despatch time can occasionally be increased.

Should you have any queries regarding this please don’t hesitate to call our sales team on 01642 455945.


We aim to reply to you either via email or phone within 24 hours Monday to Friday.