Is the emergency brake (hand operated) also "anti-lock"?

[Brian & Cate]

Curious. Was practicing a little defensive driving early this a.m. on a
empty wide section of road in a rural valley (read: It really was 6+ lanes,
no median, no traffic, clear/safe and I'm getting new tires Friday - so
don't give me any driving safety lectures please). Couldn't seem to get the
rear wheels on my 1993 Legacy to lock. Do they? Can I? How?
Thanks. Brian

 

[FUD_wad]

Curious. Was practicing a little defensive driving early this a.m. on a
empty wide section of road in a rural valley (read: It really was 6+ lanes,
no median, no traffic, clear/safe and I'm getting new tires Friday - so
don't give me any driving safety lectures please). Couldn't seem to get the
rear wheels on my 1993 Legacy to lock. Do they? Can I? How?
Thanks. Brian

Hand brakes do not use hydrolic pressure, but rather a cable (like on a
bicycle). Thus, they bypass any "anti-lock" or power brake technology.

They are also quite weak, I would not be suprised if the AWD type vehicles
prevent the classic "hand break to lock and spin" type manouver from being
possible because they simply apply more power to the rear to overpower the
brake.

[Think about it, if they were strong enough, you wouldnt be able to drive
away with them on... which you can do too.]

 

[Brian]

Couldn't seem to get the
rear wheels on my 1993 Legacy to lock. Do they? Can I? How?

The brake cable probably just needs tightening.

Contrary to the other answer to you question, you should be able to lock the
rears with the parking brake. I have never had a vehicle where I could drive
with the parking brake on. That includes by Outback Sport and my 245hp Dodge
truck.

 

[Philippe Javaux]

Curious. Was practicing a little defensive driving early this a.m. on a
empty wide section of road in a rural valley (read: It really was 6+ lanes,
no median, no traffic, clear/safe and I'm getting new tires Friday - so
don't give me any driving safety lectures please). Couldn't seem to get the
rear wheels on my 1993 Legacy to lock. Do they? Can I? How?
Thanks. Brian

<

If your car is AWD, I'm not sure that is a good idea to lock rear wheel.

 

[Eric Davis]

The parking brake on the 90-94 Legacys is a drum style brake built inside of
the
rear rotors.
Good design, hard to find the drum linings though, so I would recommend
using them only for emergencies or parking.
I don't think you could lock them up on a manual tranny car, maybe on an
auto where the torque split is different.

Eric.

 

[someone]

Does anyone know for sure if the parking brake is on the rears or on the
front on the '93? I ask because I know that the 80's decade 'roos had
the parking brake in the front caliper.

Bill Putney
(to reply by e-mail, replace the last letter of the alphabet in my
address with "x")

I'm pretty sure they only used those style on the older boxy rust-bucket
subies. I think they went to rear parking brakes with all US market Legacy,
Impreza, Forester.....

and for the original poster, it's a PARKING brake, not an emergency brake.
It's only designed to hold the vehicle from rolling when parked. It's _NOT_
designed to slow/stop the vehicle, or lock the wheels for you to play and do
slide turns........(as much fun as that may be.....)

 

[Dave Null Sr.]

and for the original poster, it's a PARKING brake, not an emergency
brake. It's only designed to hold the vehicle from rolling when parked.
It's _NOT_ designed to slow/stop the vehicle, or lock the wheels for you
to play and do slide turns........(as much fun as that may be.....)

It certainly is an emergency brake. Since (at least in the cars I've
owned) it uses a completely different mechanism from the main brake
lines, it will function (maybe not very well) when the the main system
has malfunctioned. I used it once in my Acura when the moron mechanic
didn't bleed the system. First red light (100m from the dealer) and
the pedal went to the floor. Thankfully the parking/emergency brake
was there. I'm sure their lawyers were thankful as well.

 

[someone]

It certainly is an emergency brake. Since (at least in the cars I've
owned) it uses a completely different mechanism from the main brake
lines, it will function (maybe not very well) when the the main system
has malfunctioned. I used it once in my Acura when the moron mechanic
didn't bleed the system. First red light (100m from the dealer) and
the pedal went to the floor. Thankfully the parking/emergency brake
was there. I'm sure their lawyers were thankful as well.

No, it certainly IS NOT an emergency brake, even if you've used it for such
purpose. Read your owner's or any other manual, and I highly doubt you'll
find anything suggesting that you use it as such. You will, however, find
that they instruct you to use it when PARKING the vehicle.

 

[Dan Duncan]

and for the original poster, it's a PARKING brake, not an emergency brake.
It's only designed to hold the vehicle from rolling when parked. It's _NOT_
designed to slow/stop the vehicle, or lock the wheels for you to play and do
slide turns........(as much fun as that may be.....)

They used to call it an emergency brake, and people didn't use
it for parking and "parked" cars rolled around a lot.

They started calling it a parking brake, which kept the cars
from rolling around on their own but left a whole generation of drivers
clueless about how to stop when their brakes failed.

It's a HAND BRAKE and can be used to stop the vehicle if
the brakes fail (IE, an emergency) or to keep the vehicle
from rolling around when parked.

IE, it's both a furniture polish AND a dessert topping.

-DanD

 

[Jim Stewart]

They used to call it an emergency brake, and people didn't use
it for parking and "parked" cars rolled around a lot.

They started calling it a parking brake, which kept the cars
from rolling around on their own but left a whole generation of drivers
clueless about how to stop when their brakes failed.

It's a HAND BRAKE and can be used to stop the vehicle if
the brakes fail (IE, an emergency) or to keep the vehicle
from rolling around when parked.

IE, it's both a furniture polish AND a dessert topping.

Regardless of what it's called, I know I'm going
to give it a pull if the service brakes don't work.

It's also where my hand rests when I'm riding
shotgun with my student driver daughter.

 

[Carl 1 Lucky Texan]

They certainly test it in this state as an alternate way to bring the
moving car to a halt.
I have slid the rear wheels on my '03 OBW by cranking up on the hand
brake. it's a 4EAT
FWIW

Carl
1 Lucky Texan

 

[Bill Putney]

The parking brake on the 90-94 Legacys is a drum style brake built inside of
the
rear rotors.
Good design, hard to find the drum linings though, so I would recommend
using them only for emergencies or parking.
I don't think you could lock them up on a manual tranny car, maybe on an
auto where the torque split is different.

Eric.

Good information. It's good that they went to a system like that - I
now drive a Chrylser with that same setup. The old way of having a
sloppy cable pull the service brakes to effect parking brake caused too
much interaction with proper parking brake adjustment and proper service
brake operation. I'm glad the industry finally wised up in that area.

And you're very correct: The fact that the dedicated parking brake shoes
are designed only for that purpose now means that those shoes do not
have much safety factor in them for stopping a moving vehicle (i.e.,
each incident of abuse will eat up a good portion of their design
life). With the way the mfgrs. trim everything to bare bones for weight
and cost these days, if the engineers determine that 3mm friction
material thickness will get the car thru worst-case normal vehicle life,
they might design them for 3.5mm to hopefully give a decent bell curve.

Bill Putney
(to reply by e-mail, replace the last letter of the alphabet in my
address with "x")

 

[Skweezieweezie]

If you pull up slightly on the hand brake while
coasting, you will hear the center diff uncouple
on AT equipped cars. My H6 makes a definite
"clunk" sound when it uncouples.

 

[Richard Gary Clark]

It is not a good idea to use the handbrake to lock the rear brakes on 4wd
cars with viscous center (or other limited) center diffs.

When you try, the center diff actually fights against you and puts more
torque on the rear wheels to try and keep them turning. This maybe what you
are sensing, certainly could in my EVO.
They don't recommend towing a car with this type of center diff with one
set of wheels off the ground as it will try to turn the suspended set of
wheels and if you lock them, overheat and damage the diff. Not sure if
occasionally trying to lock the rears would actually cause damage though.
The rally cars have a center diff that automatically disengages when the
handbrake is pulled.

 

[Victor Roberts]

Hand brakes (Emergency brakes) are now purposely designed so they cannot
lock the wheels of a car in motion (given a road with good traction).

Are you sure that was the design goal rather than the effect of moving
from drum to disk brakes? One of the two shoes in a standard drum
brake system will naturally "jam" against the drum when the "free" end
is pressed against the inside of a rotating drum. Disk brakes have not
such mechanical feedback system, which is why power brakes are almost
always used with disk brake systems. An emergency or parking brake
based on disk brakes will therefore naturally have far less stopping
power than an emergency or parking brake system based on drum brakes.

 

[TM]

With mechanical leverages you could perfectly achieve the forces that
would allow the wheels to lock. The problem is that the rear end of the
car would come loose and could sway from the travel direction when
driving on paved roads with a slant, same thing that happens when using
the hand brake on dirt or slippery roads with a slant.

If I am not mistaken, the hand/emergency brake on the 93 Legacy is a
drum brake system.

The requirements for parking/emergency brakes in passenger cars, are
that they should be able to keep the car still when the car is fully
loaded on a 16% incline. (Source: Bosch Automotive Technology Handbook)

I still remember the times when hand brakes were tested by making sure
that you would leave tire marks when applying them while the vehicle was
in motion and hand brakes that were applied to the rear axle propeller
shaft, which on inclines on loose roads, they would allow one wheel to
roll down hill while the other one would roll backwards (due to the
differential), with the end result that the vehicle would roll down hill.

In cargo vehicles, the emergency brake system is different from the
parking brake system. Emergency brake systems have to allow the gradual
application of the braking force, while parking brakes do not need to
meet this requirement.

In passenger cars, the parking brake allows for both functions.