DEALING WITH A BROKEN WHEEL STUD

Sweat is beading up on your forehead, the mid-day sun blistering the skin on the back of your neck and a blast of 80-mile an hour wind about knocks you over from the semi-truck screaming down the highway. You had a blow out, and now you are stuck on the shoulder of a busy highway swapping tires. Each lug nut comes off, the new tire goes on and then you start cranking down on the lugs, making sure that they are on tight, after all, the only thing worse than a blow out is losing the entire wheel. Just as the lug was snugging down to the rim, you hear a pop and you just about faceplant into the 1.5-million degree asphalt. Yeah, you really did it this time, you busted a wheel stud.

Don’t stress it too much, it can happen to the best of us. Maybe you are not even the one who busted it, the guy at the local no-name tire shop might have snapped it off and not told you about it (it happens more often that you think), the results are the same – a busted wheel stud and you have to drive around with one less lug nut on your car. As long as the others are tight, you should be OK to get home, but that stud needs to be replaced immediately. Your local NAPA AutoCare Center can handle this task for you.

We had a 2004 Mustang in the shop with a broken stud on the front driver-side rotor. The Mustang had been missing this stud since it was purchased a year ago. The entire process typically takes less than an hour to complete. The process of replacing the wheel stud involves removing the wheel, brakes and rotor, taking it down to the wheel hub. Some vehicles have integrated rotors where the hub is part of the rotor. The Mustang we have here has separate hubs and rotors. With the brakes removed, the wheel hub is exposed. The hub can be removed from this process, but it is not necessary. For rear axles with drum brakes, the brake drum must be removed, but the brake shoes and backing plate with mechanisms can stay.

Sometimes a remaining piece of the stud remains in the hub. This is usually knocked out with a hammer and a punch. If the remaining piece does not come out easily, the hub or axle would need to be removed to use a press. Once the stud is out, the new stud is installed into the hub from the backside. The new stud is knurled and must be pressed into the hole. If the hub or axle is removed from the vehicle, this is done with a press, but it can be done on the car as well. Using the disc brake rotor and a series of washers over the stud, the lug nut is tightened on the stud, drawing the stud into the hub or axle. This is a process where the lug nut is tightened and removed, slowly pulling the lug into the hub until it is fully seated.

At this point, the brakes can be reinstalled and the wheel mounted back to the car. The replaced wheel stud may loosen up after the initial torque application, so it should be checked after driving a few miles to ensure that it is torqued to spec.

Now you have all of your wheel studs in place like you are supposed to. While this is not a difficult task, there are some safety issues involved. Your local NAPA AutoCare Center has the knowledge and experience needed to get the job done and get you back on the road.