You don't say exactly what stud. If it's a wheel stud, the old one can be pounded out, and a new one pulled into place simply by tightening the lug nut on it.
If you can grab it with a pair of vice grips or even a pipe wrench and get it out then you could replace it. If that will not work you will have to buy an easy out and use that to remove the stud.
Remove wheel, brake caliper, brake disc, parking brake shoes etc. Drive out broken stud, replace with new stud. Replace above in reverse order.
Are you asking about a wheel stud or exhaust stud, please clarify
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The hub will need to be removed and the stud pressed or drilled out to be replaced.
The stud can be replaced. If you go to NAPA auto parts and order a "P19" stud kit, it will fit in and replace your broken stud.
To change a wheel stud on a Mercury Mystique, first, safely lift the vehicle and remove the wheel. Next, remove the brake caliper and rotor to access the hub assembly. Use a hammer to gently drive out the damaged stud from the back, then insert the new stud from the front, securing it in place with a nut. Reassemble the rotor, caliper, and wheel before lowering the vehicle back to the ground.
You can, but since that is the main support it would be best to replace it, preferably with decay resistant lumber.
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Notice there are two threaded holes in the brake drum. Insert a metric bolt into the holes and tighten until the drum pops off. Replace the stud.
To replace the front wheel stud on a Toyota LJ70, first, remove the wheel and brake caliper for better access. Then, take off the brake rotor and any retaining clips or bolts holding the stud in place. You can use a hammer to gently tap the old stud out from the back of the hub and then insert the new stud, securing it with a nut while tightening it to pull the stud into place. Finally, reassemble the brake components and wheel before lowering the vehicle back down.
You split the nut with a sharp chisel. Don't worry about the stud You will have to replace both anyway, just be careful with the wheel and your fingers.