[geeks] car question (RESOLVED)

[Kurt Mosiejczuk]

On Tue, 12 Mar 2002, Joshua D Boyd wrote:

> > Although to be fair, drums and shoes do cost more than pads and rotors.
> > Much more complicated metal bits in them (not just a flat sheet of metal =) )

> Under what circumstances are drums better than rotors?  Performance cars use
> rotors all way round. Most braking is done with the front wheels, which are
> always rotors.  So why do car manufactures still use drums?  To subsidize
> people for being able to charge us more?

Um, you'll note I didn't say BETTER.  I just said cost more.
Rotors are easier to make, as are pads.  Pads are just a slab of metal
with a slab of brake material glued/riveted to it.  Shoes are a curved
piece of metal with other pieces of metal welded to it for support
and mounting.  Then there is a curved piece of braking material added.
More complexity => More cost.

As to why they still use drums, all cars require an emergency/parking
brake.  It is easier to rig that up with drums, because drums are
basically mechanical, and you can just add a cable.  Disc brakes are
hydraulic and it takes more doing.  Possible, just not as easy.

As to most braking done with the fronts, that's just physics, and why
they can still put drums on the back even though they aren't as
effective as disc brakes.

> I keep considering converting my '87 jetta to all wheel rotors (rip the rear
> ones from a performance audi I guess), just to keep from having to touch
> drums because I hate working on them so much.

Feh.  Drums aren't all that hard.  Of course, I have the right spring tools.
And having done it once without them, I would never want to again. =)

--Kurt