Lately when Washington Post auto reviewer Warren Brown isn’t boring us with talk about his family he’s bashing rear drum brakes:
http://www…PRzZxou4uw
http://www…Gz7cobDm1Q
Are disks really needed to do 20-30% of the braking on an econobox?
Ford will get rid of drum brakes in the Focus SES and other cars as soon as it understands that consumers don’t mind paying extra for something that is demonstrably better.
IMO, the number of people who want lowest initial cost far outweigh those that will pay more for some marginal performance improvement over current technology that clearly meets or exceeds the demand of the typical application. The average person doesn’t give a rip about disc versus drum as long as the car stops adequately under normal usage profiles. But they are keenly aware of the initial cost of purchasing the vehicle.
Not really needed but certainly nice to have. It does reek of detroit penny pinching. Another thing, most cars today only have keyhole to unlock the car via key on the driver’s door. Of course most cars have keyless entry via remote. But should the remote’s battery fail and you’re trying to manhandle a shopping cart into position so that you might unload it on the passenger’s side door, it’s annoying,.
A local mechanic told me that discs function better for ABS ,traction or stability control applications. Wouldn’t know, but has anyone seen many later model cars with abs or stability control and drum brakes on the rear ?
If he’s bashing drum brakes he’s wasting his time. Everyone already knows disc brakes dissipate both water and heat better and the industry is pretty much moving away from drum brakes anyway.
Drum brakes in back work just fine in two of our three cars. One has ABS; no problem. Feel free to be reluctant to take auto design advice from a newspaper wordsmith.
It’s all about marketing. Drum brakes do the job, make it easier to provide a parking brake, but disks have more appeal to the unknowing consumer. That is why we get alloy wheels crammed down our throats. Steel wheels are stronger, corrode less and leak less in the long run but they are not as pretty.
"Steel wheels are stronger, corrode less and leak less in the long run but they are not as pretty."
I hear you…alloys may have some unsprung weight advantages, but too many disadvantages for winter. We always order up used steels for winters whenever a car comes with alloys.
From what I could find, disc brakes are “not” a precondition for abs and disc/ drum function fine for most cars.
Scratch one mechanic of my Christmas card list.
I have a friend who insisted on buying a car with four disk brakes. I tried to explain to him that many smaller cars with four disk brakes also have high performance tires. Sure enough, the first time he saw how much replacement tires would cost, he traded it in for a car with drum brakes in the rear.
I know the rear disk brakes and high performance tires are not necessarily related, but I still make fun of my friend for trading in a car because of the price of replacement tires. At least back when he was shopping for a new car (7 years ago), if you didn’t want to spend $150-200 per tire, you wanted a car with drum brakes in the rear.
Drum brakes are harder to service, but with my old Civic, the rear drum brake pads lasted more than the life of two sets of front brake pads. With most of the braking done up front, disk brakes in the rear only make your expensive rims look nicer. Who wants to put nice alloy rims on a car with rear drum brakes?
No, disks are not needed but they are better and simpler and easier to change (replace).
I can think of one reason why discs could be in demand: because the pads ride against the rotor, there’s no inherent “play” in the system, and produces a more precise, aesthetically appealing stopping action that one might be inclined to pay a bit more for.
For real-world applications, I’d agree that the performance and safety concerns of REAR drums are immaterial.
(Incidentally, I heard that–although discs dissipate heat better–the greater mass of drums means that they MIGHT be better for ONE panic stop vs. discs.)
If your friend balked at the cost of replacing quality parts, I wouldn’t want to ride in his car. IMHO Brakes and tires are the two most important areas where you definitely do not want to cheap out. My daily driver came with some cheesy generic tires when I got it (used). After putting up with lackluster grip and a poor ride (even by my car’s standards) for 3 months. I didn’t feel like dealing with them any more a bought a set of BFGoodrich g-Force T/A KDW-2 's. They did cost about $800 for a set, and they only last 25k miles or so but they offer much better grip and surprisingly have a better ride than the cheapo generic tires that the car originally had.
As for brakes. Again it does not pay to cheap. Brakes are a safety issue and you and by not getting the best brakes that you can afford, you are doing yourself and possibly other drivers around you a great disservice. I’ll admit I went a little overboard when I replaced the brakes on my car, I went with a Brembo Big Brake kit for the front which had larger than stock slotted rotors with 4 piston calipers up front and two piston calipers out back. Not cheap, but like I said before it’s a safety issue.
Are rear drum brakes really a safety issue on a small light weight econobox? With a set of decent Goodyear tires and stock brakes, my old (non ABS) Civic never had a problem stopping in an emergency. Many smaller motorcycles (?750 CCs) have rear drum brakes. Rear drums are perfectly fine for small light weight vehicles.
If we are talking about heavier vehicles or conditions that require more stopping power, I agree that being cheap can cost you, both with brakes and tires. Just look at how often I argue about the necessity of winter tires in winter weather. It drives me crazy to see my brother drive his kids around Buffalo, NY on all season tires in the winter, especially with his and his wife’s poor driving ability.
When it comes to tires, I think most small light weight economy cars with steel rims are safe with a set of name brand $75 tires ($300/set). The cars that come with four disk brakes and high performance tires perform at a different level than the average econobox. Those cars have a reason to have four disk brakes and tires that cost $800.
Drum brakes do not challenge a professional mechanics skills, for the DIY they can test your skills.
Drum brakes do not challenge a professional mechanics skills, for the DIY they can test your skills.
Especially if you don’t leave one side intact for reference to see where all the parts go!
I worked with a “heavy line” tech that could replace rear shoes in ten minutes per side,no B.S. but he always came to me to get the radio unlocked,we all have our “zones”
For those of you implying that the front brakes do most of the stopping so therefore the effectivity of the rear brakes is unimportant I can only respond that personally, since the rear brakes do 20% to 30% of the stopping and stopping is really really really really really important, I want to have brakes that dissipate water and heat well on the rear too!!!
I’ll take rear discs over drums any day.
I didn’t mean to imply that rear brakes are unimportant. I guess all I really want to say is that rear drum brakes should be adequate for most small light weight econoboxes with low displacement engines. If I was driving a truck, an SUV, a Mustang or an Accord, I would want rear disks too. However, on a Civic DX (one of the cheaper versions of the Civic), I think rear disks would be overkill.
As a motorcycle rider who operates the front and rear brakes independently, I agree wholeheartedly that the 30% of braking that comes from the rear is VERRRRY important.
Well I see your point Whitey, when water gets trapped inside the spinning drum and the brakes get useless, or the heat builds on that notorious downhill on the way home and the fluid boils, they’re inadequate even on a small car.
I loved the '60s and ‘70s buggys, but in truth the safety advances built into commoners’ cars today are truely invaluable. Lifesavers even.
And your bike has what kind of brakes??? (just tweaking you in good humor).
I get it. I’ll answer anyway. I have two bikes. Both are 750 CC bikes with disk brakes in the front and drum brakes in the rear. I would prefer disks in the rear for ease of maintenance, but at about 500 lbs. each, rear drums provide plenty of stopping power.
Would someone please explain why loaded 80,000 lb. tractor trailers use drum brakes if disk brakes are so much better?
Do you have to replace performance tires with performance tires?