A car or truck’s lug nuts and studs are the crucial components that hold the wheels onto the vehicle. If they fail while driving, then one would expect bad things to happen, ranging from sudden immobilization to a complete loss of control that results in a raging inferno of twisted metal. It is vital for your classic car’s safety to immediately address any broken wheel lug nut or stud.
Although it is highly unlikely that all of a wheel’s lugs will fail at once, it is always a good idea to keep your wheels mounted securely to the vehicle with all appropriate fasteners, and broken lug studs are a common problem. If left unrepaired, the improper connection of the wheel can result in unwanted vibration while driving that could affect steering and lead to premature wear in other vehicle components.
Replacing a broken wheel stud is not as hard as it looks.
Tightening wheel lug nuts without a torque wrench can be a recipe for disaster. If worse comes to worse and you break the wheel stud, here is a step-by-step account of how to replace a broken wheel lug nut stud (also called a lug bolt or wheel stud):
Prepare The Car for Broken Wheel Lug Removal
Use a wrench to loosen the wheel’s lug bolts while the vehicle remains on the ground. Then jack up the vehicle and support it with jack stands. Remove the lug nuts and pull off the tire.
Next, use a socket wrench to remove the brake caliper. Note, the driver bits required to remove the caliper pins vary among manufacturers—some require hex bits, some require star-drive bits, etc. With the caliper off the car, use a wire or zip-ties to hang the caliper from the vehicle to keep the weight off the brake line. Then, remove the caliper’s mounting bracket. (If working on a drum-style brake system, remove the brake drum.)
Remove the rotor or drum and set aside in a place where it will not be scratched or exposed to dirt or oil.
Pull The Broken Wheel Lug Stud
Place the remover around the head of the broken wheel lug stud, behind the hub. Center the driving screw over the stud and tighten it with a ratchet until the stud pops out the back.
If you are just like everyone else, you have tightened the wheel lug nuts on your car without using a torque wrench. If you are an “all the muscle you can put into it” kind of guy, and now you are staring at a broken wheel stud. You can fix tire bolts yourself in about an hour and for less than $50. You will need to buy a tie rod end remover or rent one from an auto parts store. Then buy a new stud and two new lug nuts (yes, two of them). Next, stop at the hardware store and get a handful of washers with a hole diameter slightly larger than the threaded portion of the stud. A large c-clamp and sockets may also be used.
Above all, do not directly strike the broken wheel lug stud with a hammer. That is the worst thing you can do! The hammer blows can wreck your wheel bearings and turn this into a much bigger repair bill. Instead, squeeze the broken stud out with the remover tool. It is pressed into the wheel hub, so the tough part is getting it to budge. Once it moves, the rest is easy. If you have no other choice to get the stud removed then using a propane torch to heat up the hub by the broken wheel lug stud (do not heat the broken wheel lug stud, but he area around it) and then using a large punch and hammer try to drive the lug stud out of the hub. This is only as a last resort in an emergency.
By this point, you have probably stretched the threads or damaged the bevel. So, toss the nut (they are cheap). If you cannot fit the new stud into the hub, you may have to remove the brake dust shield (drill out the rivets and replace them with stainless steel screws, nuts, and thread-locking adhesive).
Install New Wheel Lug Stud
The replacement lug stud was a stock part from a local auto parts supplier. To install the new stud into the stud bolt hole, the wheel must be turned to align the hole with a slot on the rear of the hub flange, which provides the clearance to thread it through. If the hub flange must be turned for alignment, you may have to jack up the opposite wheel so the axle can freely spin to match the hole with the slot.
For easier installation, store the replacement lug stud in a freezer for a few hours. The tolerance of the lug bolt and the hole will be very tight, and any small amount of contraction the cold temperature may cause in the metal alloy will make it easier to install the new lug stud. This will help greatly with your wheel lug stud replacement.
Use a metal-bristle brush to knock away any rust from the wheel and lubricate both the bolt and the bolt hole with a spray-on solvent. Insert the lug stud straight into the hole as far as it will go (the stud will stop at its shoulder at this point).
Thread a very large nut over the end of the new lug stud (a stack of large washers will also work). The large nut is not intended to thread onto the stud. There should be no positive connection between the stud and large nut; it should slide loosely over the lug stud like a washer to function as a spacer.
Next, thread the new lug nut over the end of the new stud, sandwiching the big nut between it and the hub flange. Use a lug wrench to tighten the nut, which will draw the lug stud into the hub until the stud head is flush with the back of the flange and snugly installed. Remove the large nut, tighten the lug nut, and the job is done. Clean the rotor with brake dust remover. Reverse the procedure to replace the brake, wheel, and tire, tightening the lug nuts to the manufacturer’s specifications.
Finally
As you can see this is one of the most common tasks you will run across on an old vehicle or on a restoration project for a vintage car or truck. Over time, they can rust or break, requiring replacement. Custom wheels may also require studs that are longer than the originals. You might think that you need to take your vehicle to a shop to replace the broken wheel lug stud, but you can usually save money and time by doing it yourself.
