Drum Brakes

[psyshack]

I wont by a car anymore that has them! Its a shame there even made for automotive use anymore. And a marketing tool at that.

If drum brakes where so good they would still be on the front wheels on cars and Large aircraft would use them still. I cant imagen having drum brakes on a motorcycle now days.

Drum brakes dont deal with water worth a hoot. They have a propensity to lock due to shoe shift in the drum. You have springs that fail alot more often that folks want to admit. They only use about 1/2 of the shoe surface in braking. Just look at the shoes sometime. Only the top half of the show wears. The bottom half is barely used unless there is a lower cam that moves the lower part of the shoe into action. also if you look at a worn shoe you more than likely will see that the inner part is worn a bit more than the outer part. This is due to flex in the drum that happens during braking.

My brother is a tool and die man and shop manager. He quotes jobs makes dies runs production, buys matrials and such.

We talked about this very same subject. Hes with me on this issue and cant figure out why cars are even built with drums anymore. So I asked him to do a mock quote on production of the two brake systems. Are drum brakes really cheaper to produce than disk? I also asked my father inlaw the same question as he owns a foundry. So casting the drums, rotors and calipers would be right up his alley. he and my brother worked on this as if they where both supplying for a large automive company.

The answer was socking! Over all drum brakes cost more to produce!

The disk and caliper casting cost more to produce than the drum. But there also a much higher quality casting and peice of work. Then it ends. The back plate of a drum brake cost alot more to stamp ot then a light weight sheild used on on a disk brake system. The brake pads of a disk brake cost almost half as much as a drum shoe to produce. Then theres the springs, pins and other small hardware in a drum system. Spring winding machines cost alot to run and maintain at a level of producing brake parts. Theres alot of quality control issues from bulk spring wire stock to production of said springs. Alot of springs if tested right would be culit. The piston in a caliper is cheaper to make than the pistons in a common drum brake. Valving and control circuts are about the same for both.

In there little excersise they came up with drum brakes costing about 20% more to produce than disk brakes. Also there was more product liablity in the drum brake systems.

I think market dept's use drum and disk brakes as a trim adder for a excuse to charge more for something that cost less to produce. IMHO drum brakes should never be used on a new production auto.

Drum brakes and disk brakes are kinda like floresent lighting and power compac floresent lighting. Or even LCD panels verses CRT.

Older flo-light systems cost more to make than compac-flo-light systems. The newer lightes put out more light per watt used! A electronic ballist is far cheaper to make than a old style ballist and the bulb production is basicly the same.

Same with LCD's and CRT's. A CRT cost far more to make than a LCD. Just making the glass tube cost more than anything in a LCD panel of the same size.

In the LCD/CRT issue Im guilty of buying a CRT recently over a LCD. No way in hell Im paying 2500 bucks for a 32" wide LCD panel to watch TV on. So I purchased a 36" Sony Vega CRT for 700 bucks. I will never ever move that god awful heavy TV again. I will take it out of this house in peices when its time comes and it leaves.

But I will never purchase a car or truck again with drum brakes. My last drum brake purchase was my 00 Ranger. I only bought it new cause I got it for under 15k new. And truley wish I had not bought it. The drums are awful on it.

[Matt Timion]

I understand a lot of your issue with drum brakes. I'm shocked that new cars are made with them, as disc brakes require less maintenance and are easier to work on.

That being said, I will not be swapping rear disc brakes onto my car. There is a weight differerence of around 25lbs between the disc brakes and the drum brakes. Every little bit of unsprung weight that I can save the better.

[Compaq888]

I don't know what you are complaining about. The only problem i have with brakes is I think ABS should be standard on all cars.

I have drum for the rear and discs for the front. My front disc brakes are huge. I can easily lock my tires at any speed, these *****es hold. I erased my last set of tires when I braked on the freeway to avoid a dog. Since then I have gotten rid of my warped disc problem and upgraded to racing pads. The pads are a little bit too much, they grip a lot more.

I'm fine with drum brakes in the rear, just make ABS because evrytime I slam the brakes my tires gets erased.

[Matt Timion]

Originally Posted by Compaq888

I'm fine with drum brakes in the rear, just make ABS because evrytime I slam the brakes my tires gets erased.

your tires vanish whenever you slam on the brakes? how weird.

[Compaq888]

Originally Posted by Matt Timion

your tires vanish whenever you slam on the brakes? how weird.

Yea, with the new brakes it's even worse. If I slam at 5mph I can give anybody sitting in the car whiplash.

[psyshack]

Originally Posted by Compaq888

Yea, with the new brakes it's even worse. If I slam at 5mph I can give anybody sitting in the car whiplash.

Compaq

You need to learn to quiver. Folks have known for years that a locked up wheel dosent stop as good as a ever so slightly rotating wheel. Train engineers, truck drivers and race car drivers lives have depended on it for years. ABS is the modern I dont have to think to hit the brakes system. And its great if people use it right.

The quiver is simply that. If you hit the brakes hard you figure out just how you have to land your foot on the pedal at hard pressures to make your leg quiver. This has a effect on the braking system like ABS. The slight quiver helps you to not lock up the brakes so early, but still allow max braking. Quiver isnt the best way to do it. Buts it the simplist. Once you find the place in your foot and leg position that causes it. It will become natural to you.

[Compaq888]

Originally Posted by psyshack

Compaq

You need to learn to quiver. Folks have known for years that a locked up wheel dosent stop as good as a ever so slightly rotating wheel. Train engineers, truck drivers and race car drivers lives have depended on it for years. ABS is the modern I dont have to think to hit the brakes system. And its great if people use it right.

The quiver is simply that. If you hit the brakes hard you figure out just how you have to land your foot on the pedal at hard pressures to make your leg quiver. This has a effect on the braking system like ABS. The slight quiver helps you to not lock up the brakes so early, but still allow max braking. Quiver isnt the best way to do it. Buts it the simplist. Once you find the place in your foot and leg position that causes it. It will become natural to you.

you mean make my leg spasm so it acts like a ABS system?

[MetroMPG]

The downside to disk brakes for me is that they're open to the elements. When you don't drive every day (and then when you do drive, you don't use the brakes much or very hard) the disk surface rusts.

Streamlining my wheel covers helped with this a little, but the front brakes are still kind of grumbly for the first km or so when I fire up the flea.

[SVOboy]

I don't mind my drums because they can stop my car. I think I should go and say I'll never buy another car over 2100 pounds,

I could swap as well, but the weight isn't worth it to me.

I'm also not a fan of ABS for myself. I am in general cuz it keeps most "slam-the-brakers" from hitting me, but I have found the point where I can stop without locking up the brakes.

*shrug*

Static friction > kinetic friction.

[tomauto]

How much more weight would rear disk brakes add compared to a drum brake setup. I was wanting to add disks in the back of my civic. I never thought of the extra rotating mass.