Drum Brakes; are there any advantages?

[ModernAndy]

Drum brakes are still fitted to the rear axle of some cars (mainly cheaper or lower spec cars as a rule). It's widely accepted that disc brakes offer improved stopping distances over drums but are there any proper advantages to having drum brakes over discs?

[MG CHRIS]

Better handbrake system, could be classed as cheaper also far better for doing handbrake turns most rear disc set up ive owned have been st for this.

[anonymous-user]

Drum brakes can be made to have a degree of self servo action. This results in less pedal load for any given deceleration. The reason disc brakes are "better" is due to their improved heat rejection. Early cars, that were light, simple and had relatively low grip tyres used drums, but when cars got heavier and tyres gripper, heat rejection started to be an issue and so most cars reverted to discs. Keeping drums at the back is largely due to cost and the easy integration of the handbrake mechanism.

[aka_kerrly]

MG CHRIS said:

far better for doing handbrake turns

this.

[Steffan]

MG CHRIS said:

Better handbrake system, could be classed as cheaper also far better for doing handbrake turns most rear disc set up ive owned have been st for this.

Spot on advice. Twin leading shoe drum brakes all round with Minifinns on classic racing Mini's (A series!!) were beloved of racing drivers when I raced Minis. The early Cooper discs were little better initially but as ever improved with development. Certainly drums are better on handbrakes at rear. However modern cars are so much more powerful I doubt if drums would be adequate nowadays.

[MG CHRIS]

Steffan said:

MG CHRIS said:

Better handbrake system, could be classed as cheaper also far better for doing handbrake turns most rear disc set up ive owned have been st for this.

Spot on advice. Twin leading shoe drum brakes all round with Minifinns on classic racing Mini's (A series!!) were beloved of racing drivers when I raced Minis. The early Cooper discs were little better initially but as ever improved with development. Certainly drums are better on handbrakes at rear. However modern cars are so much more powerful I doubt if drums would be adequate nowadays.

I had a quantum kit car as my first car with drums on the back which was brilliant for locking the back up which was great fun, now have a mk1 mx5 with rear discs and it even struggles to hold the car on a hill let alone locking the rear wheels cause the stock callipers are so crap, but as it's rwd much better at drifting.

[Gilhooligan]

MG CHRIS said:

I had a quantum kit car as my first car with drums on the back which was brilliant for locking the back up which was great fun, now have a mk1 mx5 with rear discs and it even struggles to hold the car on a hill let alone locking the rear wheels cause the stock callipers are so crap, but as it's rwd much better at drifting.

Are you sure your rear breaks are set up right? I have the same car and it's totally fine locking up the rear wheels and holding the car on a hill.

[ModernAndy]

Is the above why some cars use separate drum brakes for the handbrake action while also having discs to do all the other braking? Hadn't thought of it this in depth before.

E.g Saab 9-3, Toyota Celica mk7, Volvo S60 and plenty of other cars with rear disc brakes and handbrake shoes too

[jimbobsimmonds]

Despite the S60 having 'proper' handbrake, I still would not attempt a handbrake turn... I would know!

[calibrax]

Surprised nobody mentioned the biggest advantage... dry brakes, even in wet weather.

[mp3manager]

ModernAndy said:

but are there any proper advantages to having drum brakes over discs?

You can paint them?

[jimbobsimmonds]

calibrax said:

Surprised nobody mentioned the biggest advantage... dry brakes, even in wet weather.

Do wet discs make a noticeable difference after say the first .1 of a second? Id have thought the water would be brushed away or evaporated almost immediately. .

[jamieduff1981]

Gilhooligan said:

MG CHRIS said:

I had a quantum kit car as my first car with drums on the back which was brilliant for locking the back up which was great fun, now have a mk1 mx5 with rear discs and it even struggles to hold the car on a hill let alone locking the rear wheels cause the stock callipers are so crap, but as it's rwd much better at drifting.

Are you sure your rear breaks are set up right? I have the same car and it's totally fine locking up the rear wheels and holding the car on a hill.

Likewise both my MX-5s had handbrakes capable of locking up 205mm wide Bridgestones without undue effort on the handbrake lever. Not that I'm in to handbrake turns - but I did tug the lever on a straight road with no-one around early in to ownership to see how effective it was. A smart chirp of the back tyres confirmed what I wanted to know.

Sounds like you need to refurbish your calipers to me. Probably all gummed up and lazy.

[SystemParanoia]

ModernAndy said:

Is the above why some cars use separate drum brakes for the handbrake action while also having discs to do all the other braking? Hadn't thought of it this in depth before.

E.g Saab 9-3, Toyota Celica mk7, Volvo S60 and plenty of other cars with rear disc brakes and handbrake shoes too

my vectra has brakes like this..

Hand-brake turns like a boss

[jamieduff1981]

My Cerbera has brakes like that too. My handbrake works "well" by Cerbera standards, and can barely hold the car on a slope unless huge effort is applied to the awkwardly positioned lever. It will get separate park-brake calipers like a Vantage when I do the body-off refurbishment.

[crossy67]

calibrax said:

Surprised nobody mentioned the biggest advantage... dry brakes, even in wet weather.

Drums can get filled with water rendering them useless. I remember the signs and public info films telling everyone to try their brakes after leaving a ford or flood.

I get the heat dissipation but what effect does all that trapped dust between the liners and drum have? Can't be good. Then you have to think of the limits of the amount of pressure you can apply, you have much more contact area but it is causing tensile stresses on the cast iron drum, cast doesn't like tension.

[jimbobsimmonds]

calibrax said:

Surprised nobody mentioned the biggest advantage... dry brakes, even in wet weather.

Do wet discs make a noticeable difference after say the first .1 of a second? Id have thought the water would be brushed away or evaporated almost immediately. .

[CampDavid]

They're a bit lighter in many cases are they not?

[BL Fanboy]

Drum brakes drag less when they are released than discs do.

Less drag, less rolling friction, less fuel used, more range, less CO2 - certain versions of the latest Prius have rear drums for just this reason - to allow them to dip under CO2 limits for resultant tax reasons.

[Krikkit]

I know it's sad, but does anyone else find they have an innate hatred of drums? I think it goes back to having a crappy first car as a teen, where you were wishing for a car worthy of a full disc setup!