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New re "rear drums", as seems to come up in auto-porn, often
On inspection of the many retorts to TTAC-on-Hyun. link re the "intuitive" superiority of discs (except in after-effects of salty roads etc. in the Rust Belt and a few other ideas..)
I think I'm convinced that re drums at rear of boring-std cars (Not Hot wheels) ... there is a parallel with cycles, where the base physics is more obvious to test.

Then add-in the quips about actual records of fusslessness (in a truck, another car: both generalized too.) Any cyclist can attest to fact that, given rider-weight transfer on heavy braking, etc, the rear wheel braking is mainly about keeping a small drag (on the already unloaded "rear") merely so it doesn't end up by your shoulder.. a %high of the retarding force is via front wheel, as mere analyt.-geom. would show. Ride two-up or add sidecar? Different. (Lastly: some folks removed one of the pair of Vin. drums at rear: less unsprung weight etc, no difference in racing/braking distances etc.)

While FWD 4-wheel dynamics depend on sophistication of overall suspension, and rear brakes via ABS can help there, I'd go with the reports re light-use reliability over many years + resistance to salt corrosion -vs- discs. (though that's irrelevant to CA.) ie. What Me Worry? I don't think I'll miss the theoretical superiority on a device which won't be for boy-racer adventures; I lIke the idea that you generally Can just forget routine rear-brake *fussing (unless there were an actual factory material or design fubar, natch.)

* I'm folding in the also-general decline in Competence/Period. as regards "servicing". Skipping rear attention except periodic inspection ==> one fewer 'jobs' to have to Inspect-myself later. Y'know? Can skip the added-drag of disks, I guess.

er, What was that about the Perfect and the Good-enough? ;^>
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(Ok, OK..) the magnesium brake-plates for the Shadow didn't 'transform handling' ... either :-0
but they were Purty. :-)

[/bench-racing]
New I know about the long-gone "joys" of brake jobs, too!
Yeah, not fun.

Dunno how common it is, but my Jetta wagon had the rear pads replaced about 40,000 miles ago while I'm still on the original front pads. It's supposedly pretty common on these things.

I think we spent about $600 having the brakes on J's Corolla done, and most of that was for the rear. :-/

Yeah, drum brakes are pretty-well perfected technology, but I always hated doing drum brake work. All the dust, all the rust, the rats nest of springs, the invariably broken bleeder screws and having to replace the wheel cylinders, meaning bleeding the lines, etc., etc., etc. It's so much easier to pop off the caliper, push the cylinder back in, install the new pads, and put the caliper back on. (Of course, there are apparently pathological calipers out there that have the pistons screw out and require a special tool/technique to get them to retract. And one probably has to ship the Veyron to France for a brake job... ;-)

Yeah, for an about-town daily driver, going from drums to discs isn't worth some $3000 options package, or something. But I'd still look for them, myself when I go shopping again in the distant future. Even if I don't have to do the brake job any more, paying Moe's Garage to do it, well... :-)

Happy hunting!

Cheers,
Scott.
New Having done 4-wheel drums, and 3 disks (two front, one rear) on a bike ...
I just can't get my head around the difference in complexity. The bike took literally 15 minutes to put new pads on all three disks. The car -- which was old enough to have drums front and rear -- good lord, that was a two-man job that took most of an afternoon, what with the bleeding and the springs and ... yeah, what you said.

I can't think of any (even theoretical) advantage of drums that would make up for that.
--

Drew
New Wikipedia has a list of advantages.
https://en.wikipedia.org/wiki/Drum_brake#Advantages

Physical complexity is one of the Disadvantages. However, that they work better for parking brakes over discs is a big Advantage.

Wade.
Expand Edited by static Jan. 22, 2018, 04:13:05 AM EST
New Wikipedia constantly amazes me
--

Drew
New As to mfg. 'strategies':
I noted that, on friend's Acura/Integra: the discs at rear were smaller (dia. maybe thickness too?) At first glance seemed a decent engr. tradeoff: rear helps-Less; less *unsprung weight, etc.
* Now try to 'Quantify' the/any..? noticeable improvement in vehicle handling. {{sigh}}

Then one enters the Capitalist-also-carmaker mind:
Via this McGuffin they can remind owners: do ALL the brakes at once (and if their arithmetic was OK, the pad-wear should Make It So.)
But this plan maximizes the labor -vs- say, doing Rears maybe every-other Front or even every third? Front-pad replacement.

Homo-sap: the Lying species ... at Work.
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.
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Still nothing ever IS 'simple': that guaranteed inspection/replacement at rear can reduce chance in Rust Belt of those rear calipers loading up with corrosives.
(Forget the rationale via which the rears are more prone.. maybe for being out of airstream that Fronts live in.)
New I didn't realize until recently that the front brakes do much more work.
Front wheels on my car are much dirtier from brake dust than the rear ones.

Wade.
New Oh yess..
I forget the envelope calc re a Detroit lead-barge (like re my short-term '70 Buick Riviera, scored for a *pittance at opportune time): just amid the '73 Petro-Robber-cartel's sudden uppance of $$/bbl
and the ƒeare engendered in ... (those same non-physics buyers of our Insolent Chariots [book title du jour]; guzzlers All, then..
Gawd but Murica has always been the King-of-Waste in all things bought to show-off one's disdain for any need to economize or otherwise Think.

IIRC it came to ~500 HP equiv. power/to the energy-sink ...those poor drums, in a near 1-G stop! (one could see the incandescence of the front drums at night; I forget the calc. of much less work by rears.


Opt war-story
* I matched dealer offer for a trade-in for a friend's "conscience placation?" ..on an Audi.
(Colin Fletcher: author, the guru of Walkers everywhere, suddenly realizing that 'ecology' meant that his pristine Riviera was a pretty poor icon re conservation matters.)
'Twas n authentic G.T. with which I once went head-to-tail with a sports car driver who had cut moi off. While it weighed 5000# (!) it had the torque, brakes, handling
to be a sleeper Detroit muscle-car. Rude driver was startled to see this behemoth right on tail through twisties, etc.
Loved. It. I told Colin that, if the gas-lines remained long, I could just park the sucker in driveway; run it on hot days and sit in air-conditioned splendor. :-þ

Paid ~$1200 for this cherry monster; sold it a couple years later for ~2500; subsequent callers were each crushed to have missed it. (I didn't do homework/ no Web then.
This car was already a Legend. (No, not Acura) and had I been smarter it might have cadged a couple grand more. Oh. Well.
New Engineered to not lock the wheels
With the added caveats of a clean, dry, solid road surface and tires in good condition, the brakes are designed to not overpower the tires when properly applied*. The rears are smaller, even on a car, because the weight transfer to the front would make larger brakes overpower the reduced traction. And a locked rear end will soon overtake the front end...

Properly applied: start light to give the front suspension time to load up, then keep building pressure. It goes fast enough so it is not like you have to set it up 1/4 mile ahead of time.

That all said, my last two cars' ('08/'15 Subaru WRX) rear brake pads went at 24k miles whereas the fronts lasted much longer (36k/???). Similar characteristics noted for the Missus' Toyota UAVs.
New Possible handling advantages are probably secondary...
...to general weight saving (fuel economy) and above all, manufacturers' cost savings. You just don't need as big brakes rear as front, so why waste a milli-cent more than necessary on them?
--
Christian R. Conrad
Same old username (as above), but now on iki.fi

(Yeah, yeah, it redirects to the same old GMail... But just in case I ever want to change.)
     Brand badges don't mean much these days. - (Another Scott) - (27)
         I dont shop cars by brand anymore - (boxley) - (6)
             My list - (drook) - (5)
                 Ulp.. - (Ashton) - (3)
                     I haven't paid much attention. - (Another Scott) - (1)
                         I had a Pontiac Grand Prix once ... - (drook)
                     I'll look into that, thanks for the tip - (drook)
                 Re: My list - (pwhysall)
         Been happening for a long time. - (static) - (1)
             VW: From MAN and Scania via Bugatti, Bentley, Lamborghini, Porsche, Audi down to VW, SEAT and Skoda. -NT - (CRConrad)
         Yabut.. at least TTAC lends gravitas to the unravelling, eh? :-þ - (Ashton) - (11)
             Nice. - (Another Scott) - (10)
                 re "rear drums", as seems to come up in auto-porn, often - (Ashton) - (9)
                     I know about the long-gone "joys" of brake jobs, too! - (Another Scott) - (8)
                         Having done 4-wheel drums, and 3 disks (two front, one rear) on a bike ... - (drook) - (2)
                             Wikipedia has a list of advantages. - (static) - (1)
                                 Wikipedia constantly amazes me -NT - (drook)
                         As to mfg. 'strategies': - (Ashton) - (4)
                             I didn't realize until recently that the front brakes do much more work. - (static) - (1)
                                 Oh yess.. - (Ashton)
                             Engineered to not lock the wheels - (scoenye)
                             Possible handling advantages are probably secondary... - (CRConrad)
         That's nothing. Behold the Aston-Martin Cygnet: - (CRConrad) - (5)
             I've seen one of those in real life, parked in our neighborhood. - (Another Scott)
             Wonder what Q branch could do with one of those?... -NT - (scoenye)
             That was mad as a box of frogs. - (pwhysall)
             Now see the [only..] one with a V-8 - (Ashton) - (1)
                 Guess that answers my Q branch question - (scoenye)

Jane! Jane, get me off this crazy thing!
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