With a Wheel Bearing Hub Assembly, you might get both the wheel bearing and the hub assembly. Sometimes, especially with FWD vehicles, the front hubs will not have the bearing with them but the rear hub assembly will. Most part manufacturers will follow what ever the auto company recommends.
Well its a wheel bearing hub assembly that you need to buy. Autozone has a Timken/Wheel Bearning/Hub Assembly-front its $79.99 and they have the Duralast/Wheel Bearing/Hub Assembly-Front $51.99
Behind the wheel?
It is extremely important. A defecting hub assembly or wheel bearing can cause you to have an accident.
you have to replace the wheel bearing hub assembly look up a picture and you will see the bolts are attached to the hub assembly.
The wheel bearings are not really replaceable by themselves. This is because they are integrated into the hub assembly. So the answer is that you will have to replace the entire hub assembly to replace the bearings.
Year make model would help. Probably you are referring to a hub assembly in a passenger car. A hub assembly contains the wheel bearing, and the hub to mount the wheel to. Many also contain the anti lock brake system wheel speed sensor which makes them very expensive in some cases.
The frontdoes not havea "wheel hub assembly". It is an individual sealed roller bearing that has to be pressed on and off the front spindle. It is a Toyota thing!
The wheel hub is visible when the wheel is removed from the vehicle. It is the circular part that is used to actually mount the tire/rim assembly to the machinery of which it is a part. The hub assembly acts as a carrier for the mounting lugs/bolts, and generally for the wheel bearings.
the same way you would replace any hub assembly, take the wheel off, take off any bolts that connect the hub to the driveshaft and then replace it
http://www.paulstravelpictures.com/GM-Wheel-Bearing-Hub-Assembly-Replacement/index.html
the wheel speed sensor is all part of the wheel bearing hub assembly you cannot clean them you have to replace the hub assembly its not that hard of a job gm cars are known for this problem.