you can't use a nylock nut as the plastic portion just melts
I'd reccommend to use something like an 'aerotight' nut which are all metal
or a 'K-nut'
you don't use threadlock on an exhaust fixing as it just gets too for the loctite so thats not an effective solution
a spring washer can help and these are fitted as standard on some cars but this an old solution and not very good
the modern fittings used are the metal locking nuts that I've already described and they are often a plated nut to help prevent corrosion locking it in place
do you still need help?
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