What's inside those wheel hubs?

The brakes were doing a lot of squealing this spring, so I figured it was time to take them apart and give them a good cleaning. Also a good reason to satisfy my curiosity about just how these things actually work.

Bought a little bottle jack to raise the Alto, as my attempts to use the screw jack from the Santa Fe proved awkward.  A recommended purchase, for those times you need to use it to change a tire.  This will make the job much easier.  You can also see a small jackstand there, which is a wise safety precaution, and easy to keep in the car as well.
Inside, it is pretty much a normal drum brake, except what expands the shoes is a magnet, rather than a hydraulic When energized by the brake controller, it grabs the inside face of the drum, and as it gets pulled along by the rotating drum, the lever the magnet is attached to, twists a cam which forces the shoes out to make contact with the sides of the drum.  The more voltage applied, the harder the magnet sticks to the face and the stronger the leverage on the shoes. Pretty ingenious.

When the drum gets pulled off the spindle, the outer wheel bearing, held in place by the spindle nut, comes out of its race.  Lots of grease everywhere, which is a good thing.  Next spring, the job will include a full repack of the bearings.


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