I suppose I should throw my 2 cents in on drum brakes. I grew up with them and disks are still new technology to me.
- Drum brakes have a different set of maintenance issues than calipers/disk brakes.
- A hard to remove drum is a sign of poor maintenance practices. If the ridge is not removed or the drum turned when the shoes are replaced the ridge will become so high that interference with the shoes will prevent or make difficult the removal of the drum.
- Rusted on drums can easily be loosened by firmly striking the area between the studs with the ball end of a ball pein hammer. Don't try this if you have poor hammer skills, you'll bugger the studs.
- On a drum that has a ridge that prevents easy removal it is sometimes possible to "unscrew" the drum by firmly pulling it out while turning the drum back and forth.
- Trying to force the drum with pry bars frequently leads to the shoes getting cocked and like a Chinese finger trap, makes it all the more difficult to remove the drum.
- Manipulating the star wheel is a skill. It requires knowing which way to turn the wheel. Some vehicles use left and right hand threads depending on which side of the vehicle they are on.
- Always replace the rubber plugs on the star wheel holes. Don't forget the bleeder plug caps too. They are not there for looks.
- Proper care of drums includes turning them or replacing them during shoe replacement.
- Drum diameter does matter. Make sure both drums on an axle have the same ID.
- If you have a bad memory, a digipic of the innards of each brake taken before dismantling can preclude a second R&R of the brake drum to get all the gadgets in the right place.
- Replace the springs on every service if you live in salt land.
- Before disk brakes people used metallic linings to prevent fade. They also got used to having less than effective brakes till warmed up.
- Drum's reputation for fade was due in part to manufacturers using undersized brakes. The disks that replaced them were heavier anyway. Porsche for example used a steel liner in an aluminum drum on some models.
- Drums are inherently better protected from foreign matter and splash. They also tend to be lighter.
- Properly adjusted drums have less drag.
- Effective drum brake systems can be designed that don't require a power booster due to the self energizing feature in many shoe designs.
- Drums lend themselves to a simple emergency brake system.
- Drums are not as particular to machining and manufacturing tolerances as disks.
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