What Are Stud Clips On Vehicle Hubs?
Stud Clips
Many American built cars and trucks have small retention clips mounted at the base of the studs. These stud clips were designed to secure the brake rotor or brake drum to the hub as the vehicle was moving down the assembly line in the factory. Once the brake calipers and pads are installed, they serve no real function. The clamping force of the wheel and lug hardware is what keeps the assembly together once the wheels are installed and torqued down. These clips are usually discarded the first time a brake job is done on a vehicle. If left on the hubs, the stud clips can cause major vibration issues and damage to the wheel and the vehicle when aftermarket wheels are installed. If your vehicle has these on the studs, they need to be removed before you install your new wheels.
Stud clips are only found on vehicles manufactured by GM, Ford, Chrysler, Saturn, and other domestic manufacturers. They look like a thin, toothed washer mounted around the base of the stud. They will normally be found on one or two of the studs and may be difficult to see if there is corrosion on the hub surface. Unlike the O.E. wheels, most aftermarket wheels do not have a machined recess on the mounting pad to clear these clips. Mounting wheels on top of these will keep the wheel from sitting flat against the hub surface. If a wheel is mounted down on top of one or more of these it will still be possible to torque the lug nuts to the correct spec, but they will not hold that torque setting for long. The harder steel stud clip will quickly embed itself into the back of the aluminum wheel mounting pad. This will be most noticeable as forces from braking and turning the vehicle place additional stresses on that contact area of the wheel and the hub with the stud clip wedged in between the two. As the clip digs into the wheel pad, it will cause the gap between the wheel and hub to disappear, allowing the lug hardware to loosen up in the wheel. This results in severe vibrations, especially when braking and turning. All of that can damage the lug seats of the wheel, the studs, and the hub studs resulting in the possible loss of the wheel.