The OLD GU gearbox is suitable for the older type of GU multipoint locking mechanisms . It is an easy to change gearbox and will swap over with just a starbit that comes free with the case.
The gearbox has a deadbolt and a latch, and the backset is available in a 30mm or 35mm backset. Please check you have measured your backset correctly before ordering (See image below)
Please check your gearbox to make sure you have the old type. The biggest way of telling is the top corner is missing on the old type; to see the new type click here.
The latch is easily turned around to suit both left or right handed UPVC doors.
Simple steps to help you choose the right size backset for your Gearbox
The Backset size is A in the diagram
Measure from the the front of the main faceplate (A in the diagram) to the middle of the spindle hole. This measurement is taken when the gearbox is attached to the main front face plate.
Measurement B is the PZ Centre.
Frequently Asked Questions
You need to measure the pz (shown as “A” on our guide) and the backset (shown as “B” on our guide).
Click here to go to the guide.
This depends on your existing gearbox and whether an alternative is available and we always have to match up with the existing “holes” in your door. Call us on 01204 652211 and we can help you with this.
The most common bit used to remove a gear box is a torx t20 although in some instances a square drive can be used which can normally found in most drill bit sets.
A Dual spindle has 2 spindles at different heights. This means that the levers / moving parts of the door handle will be at different levels on the inside and outside. A Split spindle is made of 2 parts that meet inside the gearbox. The levers / moving parts of the door handle will be at the same level. A Single spindle is one long part which goes right through the door. The levers / moving parts of the door handle will be at the same level. To distinguish between a split and single spindle you will need to remove them from the door and look.
No, as you do not necessarily need to change the barrel when changing the gearbox so the gearbox is sold on its own own. If you need a new cylinder, please click here.
We try to put these guides on each gearbox page. If its not there please call us on 01204 652211 and we’ll find the instructions for you.
Unfortunately not all gearboxes can be purchased separately. Contact us if you can’t see your gearbox on our website and we can tell you if its available or not.