Australian Car Repair Issues? Ask an Auto Mechanic for Answers ASAP
It doesn't have a thread inside, probably just rusted frozen inside the knuckle. You'll need a breaker bar or anything that you can get some good leverage on the bolt with to turn it and break it free. If you can't break it free, the only other option is to spray it with penetrating oil or heat the knuckle up with a torch and then try hitting it with the hammer to get it out. Good luck.
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