Wheel bearings come in two main mounting styles, and which one your vehicle has changes how the job is done. Here is the difference between pressed-in and bolt-on wheel bearings.
Bolt-on hub assemblies
Many modern vehicles use a bolt-on hub and bearing assembly - the hub, bearing, and flange are one sealed unit that bolts to the knuckle; see signs of a bad hub bearing. Replacement is straightforward: unbolt the old, bolt on the new, torque to spec; see hub torque.
Pressed-in bearings
Other vehicles use a bearing that presses into the knuckle or hub, held by a retaining ring. Replacing it requires a hydraulic press or special tools to remove and install the bearing without damage - a more involved job often left to a shop.
Which does your vehicle use?
Front-wheel-drive cars and many trucks often use bolt-on assemblies; some cars and older vehicles use pressed-in bearings. Check what your vehicle takes before ordering, since the parts and tools differ.
Either way, torque matters
Both styles rely on correct axle-nut and hub torque for bearing life; see hub torque matters. Do both sides on high-mileage vehicles. Keep the brakes fresh with quality pads and hardware.