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Yes the key has broken and I can't ket the (locking) wheel nuts off.
Suggestions?
Drill? Nope..hardened
Socket bashed on the outside? Nope they have a spinning collar
New key? maybe?
Help!

A locksmith may be the only answer. They can usually make a new key, but it could still be tricky removing the broken key blade. Most manufacturers changed from keys to puzzle nuts many years ago for this reason.
You don't say what make or model of vehicle you are referring to, however, some Service Departments may have a selection of keys for you to try - but it may take a while to find the right key from a box of hundreds!!