What is the purpose of the parking/emergency brake?

[rbattelle]

I've been operating for years under the belief that the parking (or emergency) brake is designed specifically so that it's cable operated and not connected in any way to the hydraulic brakes. That way, if you lose all your hydraulic brakes you can still stop the vehicle.



Is that incorrect? I ask because I was reading an article today about the new electric park/emergency brakes that will be coming out on some luxury brands. They use a small electric motor at the brake so there's no cable.



I guess the failure rate on modern hydraulic brakes is small enough that safety regulations no longer specify a backup?



Ryan

 

[scootergmc]

I just use my e-brake to keep pressure off the transmission pawl.

 

[bmoeller]

Same here, but only if I am towing something. Use it the most when I'm moving fertilizer buggies. Have to park on bit of a hill where we load them up, and can be a bit tricky to get out of park.

Don't know how they will be setup, but the motor might be attached to axle. No cable needed then.

 

[lmills]

I've been operating for years under the belief that the parking (or emergency) brake is designed specifically so that it's cable operated and not connected in any way to the hydraulic brakes. That way, if you lose all your hydraulic brakes you can still stop the vehicle.



Is that incorrect? I ask because I was reading an article today about the new electric park/emergency brakes that will be coming out on some luxury brands. They use a small electric motor at the brake so there's no cable.



I guess the failure rate on modern hydraulic brakes is small enough that safety regulations no longer specify a backup?



Ryan

Always heard the same thing. Back up system in case the hydros failed

 

[fkovalski]

... . Back up system in case the hydros failed

Back in the day in tech school... we were told just the opposite.



There is no such item as an "emergency" brake. If it happens to stop a vehicle in such a situation, then count your lucky stars. It was always refered to as a "parking" brake to hold the vehicle in place while running, on a manual tansmission car (which back in the day all cars were of this type. )



Don't this as fact as I hear stuff to contradict what I was told...



But think of it this way: If one were to have presence of mind to in fact use the "Emergency" brake (i. e. stepping on it in a panic)... . it could not only lock up the wheels but stay locked! Braking in panic does not neccesitate completely locking the wheels. It could be worse than the initial situation.

 

[jkalchik]

I've been operating for years under the belief that the parking (or emergency) brake is designed specifically so that it's cable operated and not connected in any way to the hydraulic brakes.

Your first statement is mostly correct. Parking and emergency brakes are designed to be as independent from primary braking as reasonably possible. For a lot of years, a cable operated system has been used. Looks like someone has the reliability factor on another method up far enough.



One of my sidelines is off roading. I know a number of folks who have gone to a transfer case mounted emergency brake. My issue with this is that it doesn't work if the driveshaft or u-joint fails.



I should also point out that both my CTD and my Heep are stick shifts. The parking brake gets sets whenever I get out.

 

[TowPro]

I bet you don't find it called an "emergency brake" in the manual, its a parking brake. the same as "guard rail" on the side of of the road is now called "guide rail" since it don't guard you from flying off the highway.

if you ever drove a manual, you would use the parking brake so you can find the truck in the same location you parked it

 

[nickleinonen]

i use it for parking exclusively. on all the vehicles i drive. . stick or slushbox. .

i wouldn't trust a parking brake/emergency brake for any movement related braking... live where there is rust/snow/salt and push on a parking brake hard enough, the cable will snap. i've personally broken 3 parking brake cables on various vehicles that are not regularly rust protected sprayed. .

 

[lmills]

OK... .....





http://en.wikipedia.org/wiki/Hand_brake



First line says it all. :-laf

 

[rbattelle]

But think of it this way: If one were to have presence of mind to in fact use the "Emergency" brake (i. e. stepping on it in a panic)... . it could not only lock up the wheels but stay locked! Braking in panic does not neccesitate completely locking the wheels. It could be worse than the initial situation.

I specifically remember a drivers Ed. video that discussed how to handle failed service brakes. You hold the emergency (parking) brake latch with your hand and operate the brake. We practiced it in drivers Ed. I have practiced this innumerable times myself so that in an emergency I have no doubt whatsoever that I WILL go for the parking brake if the service brakes fail.



That's one of the reasons I HATE the GM parking brakes where you press on it to set it, then press it again to release it. Almost totally useless in an emergency.



Ryan

P. S. I always always always set the parking brake in every vehicle I drive.

 

[MCummings]

Ever tried to stop a vehicle with the parking brake? If you don't lock the brakes, it'll probably fade away before you come to a complete stop.



The parking brake is only to keep the vehicle from rolling once stopped. If you are on a slick enough surface, the transmission might keep the driveshaft from spinning, but that doesn't mean one tire won't turn forwards while the other spins backward...





Merrick

 

[fkovalski]

Great post and converstations thereof but, should we ask the Mods to place this in the "Other Vehicles" forum for more input other than us who lurk the "Other" forum... ?

 

[4xquadrod]

I always thought it was for doing power slides. :-laf

 

[CRuth]

Your first statement is mostly correct. Parking and emergency brakes are designed to be as independent from primary braking as reasonably possible. For a lot of years, a cable operated system has been used. Looks like someone has the reliability factor on another method up far enough.



One of my sidelines is off roading. I know a number of folks who have gone to a transfer case mounted emergency brake. My issue with this is that it doesn't work if the driveshaft or u-joint fails.



I should also point out that both my CTD and my Heep are stick shifts. The parking brake gets sets whenever I get out.

You have to be kidding! The worst part of the old jeeps was the transfer case mounted parking brake. Someone would willingly install one? Most of us ripped that pos out years ago. It works for about a week when its new.

 

[fkovalski]

On the old VW's... the parking brake cables were 2 individual cables that ran up to the center console between the 2 front seats... . there was a kit, which could be added that allowed the operator to convert the single handle to 2 individual "pull" handles such that each rear wheel could be engaged individualy! It was handy back then... and could be usefull if such a kit could be made for our trucks today!

 

[jkalchik]

You have to be kidding! The worst part of the old jeeps was the transfer case mounted parking brake. Someone would willingly install one? Most of us ripped that pos out years ago. It works for about a week when its new.

Nope, I'm not kidding. Makes it easy to use a couple of front disk brake calipers on the rear end.

 

[AfterBurner]

I always thought it was for doing power slides. :-laf

Finally, someone stated the real reason! I can't believe it took so long for someone to say this, ya'll sound like a bounch of old people:-laf

I drive a manual and it's still an e-brake to me, and i've driven too many trucks on which the ebrake didn't hold to trust them. If on a slope shut it down, and stick in gear. Even if you have a good one, it still won't hold a load which is the only time I'd want to leave my engine runnig at $3 a gallon anyways.

Forrest

 

[Joe G.]

If you tried to stop in an emergency with our parking brake you would be lucky to stop in the same county.



Old Mopars used a band around a drum on the end of the transmission. Those things would stop you if you didn't break the drive shaft.

 

[ToolManTimTaylor]

I just use my e-brake to keep pressure off the transmission pawl.

BINGO!



And truth be told in every manual in every manufatcurers vehicles it is called a PARKING BRAKE ... not an e-brake as it has become to be known.

 

[Joe G.]

At one time it was an emergency brake, but those days are long gone.