Video tutorial on how to check the runout on a hub. Hub runout is the lateral movement, which is the hub running off center. This can cause mild to excessive vibrations depending on the severity, either in the steering, throughout the whole vehicle, or brake pedal. Depending on the severity of the runout, this can cause parts to wear quicker or create premature failure. Excessive hub runout can be causes by a poorly machined surface, a bent hub, or worn bearings. It’s also important to check hub runout when checking a rotor for runout if both assemblies are separate. So that would mean the rotor, hub, and wheel bearing isn’t one assembly.
- dial indicator
- mounting hardware for dial indicator
- magnetic base or clamp
For this you will need a dial indicator and mounting hardware. Normally you can use a magnetic base, but in this case most of the suspension components are made of aluminum. I don’t have a clamp mount so instead I’ll use a bolt to connect it where the brake caliper carrier mounts to. Preload the dial indicator, I would recommend about 0.050” and make sure it runs on the furtherest point from the center of the hub face.
It’s important to measure the furthest point as this will show the maximum runout. Zero the dial indictor by rotating the face and tighten the lock. Rotate the hub and watch the dial. Here we have less than 0.001” of runout which is good. Maximum allowable runout will depend on manufacturer specifications, so be sure to consult with your vehicle’s specs first.