I've lost my locking wheel nut key — how can I change a flat tyre?

May 18, 2023

Locking nuts are sold with a code, so owners can order a new key from the maker. If you don’t have the code, garages have tools able to remove most nuts. Breakdown organisations such as the AA and RAC can also usually help.

There are locking wheel nut removal tools available from the likes of Amazon, which you hammer over the nut to cut a reverse thread, then use a wrench to unscrew it. They destroy themselves during application, so they’re single use items.

A last-ditch DIY solution — provided you have a simple type of nut, without a spinning outer shroud/collar — is to take an old 12-point socket that is a little too small, hammer it until it bites onto the nut, and then twist it off with a ratchet. Don’t try this with a high-spec locking nut from the likes of McGard, though: you’ll destroy the wheel.

Locking wheel nuts, also known as alloy wheel nuts and lug nuts, require special socket tools with a matching pattern, which is bespoke for the nut — much like a lock and key for a door. Each car has four nuts (one for each wheel) and one key.

The idea is that while thieves may be able to remove the other nuts on a wheel, which have standard hexagonal heads, the locking nut is not so easy to remove. The time it takes to force it off may not be worth it due to the risk of being caught.

If you haven’t used your locking wheel nut key since purchasing your vehicle, it’s likely to still be where the manufacturer stored it. Try checking the following places first:

If you’ve used it since you bought the car and it’s not in any of the above locations, try checking your cup holders, car door pockets, ash tray and any other compartments.

Still can’t find it? Follow our advice above and order a replacement locking wheel nut key from the manufacturer (you’ll need the locking nut code) or speak to your breakdown organisation who may be able to help.

Locking wheel nut removal isn’t too dissimilar to the process of removing standard wheel nuts. One end of your locking wheel nut key is likely to have a hole that will fit a standard wheel brace. Slot the other end — the keyed end — onto the locking wheel nut and turn the wheel brace anti-clockwise until it loosens. Once it’s loose enough, you can remove it with your fingers.

If you’re removing a wheel due to, say, a flat tyre, just remember the order of operations: partially loosen the wheel nuts before jacking up the car and only remove the nuts fully when the wheel is fully jacked off the ground. In reverse, only partially tighten the wheel nuts before letting the car down off the jack and give them a full and final tighten when the car is back on the ground.

As we mentioned earlier, there are a few different ways to remove locking nuts without a key, including:

No, although most new cars will now come fitted with locking wheel nuts as standard.

If you’re unsure whether you have locking wheel nuts, try the following:

1. Inspect your wheel nuts — if one has a pattern then this is a locking wheel nut.2. Check to see if any of your wheel nuts have a plastic cover (which gives all the wheel nuts a uniform appearance) – if they do then this will be the locking nut.3. Place a wheel brace or nut spanner on all five nuts to see if they grip — but don’t use any force. If the brace fits on all of the bolts, then you don’t have a locking wheel nut.

Lost your locking wheel nut key? Don’t worry, each key comes with a code so that you can order another from the manufacturer.

You can often find this code in the owners handbook, service book, or on the locking wheel nut box or bag, if you have one.

There are three main types of locking wheel nut used on cars today.

Yes. If you drive an older car that came without a set of locking wheel nuts or if you’ve fitted a nice set of aftermarket wheels and want to protect them, there are a wide range of locking wheel nuts on the market. Among the toughest and most highly-regarded are those from American firm, McGard. As well as selling to consumers, McGard supplies locking wheel nuts to car manufacturers. There are less pricey options out there though from Halfords (which, incidentally also stocks McGard products) and others.