Anti-lock brakes...and that's ABS...work mostly in the rain or snow. On dry
pavement and with the wheels straight...a car will most often make a
emergency stop without any wheel lock-up...and that's due to
electronic-brake-balance along with modern tires.
But check out your anti-lock brakes with a drag-test to make sure they are
not costing you. Drive by a sign on the Interstate at 70 MPH, then let the
car coast down to 40 MPH, and note the distance the car coasted. Now take
the fuse out of the ABS, repeat the drag-test, and see if the two coasting
distances are the same...
Okay...put the fuse back in the ABS.
Not if you have good brakes, good reflexes, and aren't afraid to give
the brake pedal a good healthy shove. A car will stop a heck of a lot
faster than most people have ever braked. If you're truly panic
stopping, as in if you need to stop RIGHT NOW and don't know if you have
enough space to do it but gosh darn it you're going to try, on dry
asphalt and you don't feel the ABS kicking in (ASSuming an ABS-equipped
car) you're not pushing hard enough.
Now, in a non-ABS car, the trick is to NOT lock up the wheels - because
the coefficient of friction between tires and asphalt is significantly
less when sliding as opposed to rolling - but to get as close to that
point as you can without actually locking the tires. In practice what
happens is a good driver will stab the pedal hard, then let off slightly
when he feels the wheels starting to lock, but no more than necessary to
keep 'em rolling. Only way to do that is practice...
replace "roosters" with "cox" to reply.
Forgot to mention, getting a little OT... tires play a big role in
braking performance. Some tires have so little traction that they are
trivially easy to lock up, when braking not much more assertively than
normal. GOOD tires will smash your eyeballs against the back of your
glasses when you really mash the stop pedal. You ought to be able to
panic stop at close to or above 1G on dry asphalt in a modern car with
Examples of the former category of tire that I've experienced would be
the Goodyear Integritys that GM seems to put on everything, or the
Continental all-seasons that came stock on my '02 GTI (why you'd equip a
car with so much torque with such lousy tires I'll never understand -
maybe the ease of doing big, smoky burnouts was a selling point?) or
General Ameri-anythings. The latter category includes, in my
experience, anything with Michelin Pilot on the sidewall...
replace "roosters" with "cox" to reply.
No...electronic-brake-balance and modern tires...eliminates wheel lock up on
dry pavement...when the wheels are pointed straight.
Now race cars have mechanical-brake-balance and no problem with wheel
lock-up during a long, long, history of motorsports. In fact in setting up a
race car...there is only brake size, rotor size, tire size, and
mechanical-brake-balance. Well...a race car brakes the same way every time
and only needs one brake-balance rather than a variable brake-balance of an
electronic-brake-balance. But again...there can be uphills and downhills on
a racetrack so the most modern race cars MIGHT have an
With the correct amount of brake-balance...there is no wheel lock-up on dry
pavement with the wheels pointed straight. (On most race cars there is no
adjustment other than brake-balance. Now modern street cars
have...electronic-brake-balance that reduces brake hydraulic pressure to the
rear brakes as the brake pedal is pushed harder.)
ABS essentially unlocks a wheel that is locked-up. Well...a wheel
approaching lock-up is turning slowly...and then the ABS kicks-in. So ABS
most often works on slick roads or when emergency braking with the wheels
For a loose definition of "modern." It's quite possible to get wheel
lockup in my '55 Stude with manual drum brakes. Very good manual drum
brakes, but still.
*NOT* being able to lock the wheels on dry pavement is a sign that your
brakes aren't good enough.
replace "roosters" with "cox" to reply.
Since when could cars NOT lock their wheels?!? The 30s maybe? My 1949
Plmouth Coupe certainly can lock its wheels when I stand on it (with no
power brakes at that, but it does have 6 wheel cylinders.)
Brake proportioning valves (what you guys are calling "balance") came
into existence way back in the 50s or earlier. Their job is to take all
4 wheels to lockup at the same time, not have the rears lock far before
the fronts reach maximum braking potential or vice-versa. Proportioning
can't compensate for one or more wheels being on slipperier pavement
than the others, but it can and DOES equalize all 4 wheels when they
have the same traction (allowing for weight transfer from rear to front
as well). ABS does the fine-tuning to keep an individual wheel from
locking, or its supposed to. What drivers fail to realize is that when
ABS kicks in, you are BY DEFINITION using less than 100% of the car's
braking ability. You sacrifice braking power to improve CONTROL during
braking. Something that's really best done by a competent driver, not by
Not necessarily- that depends on the ABS implementation. Better ABS
systems still have a mechanical proportioning valve assembly so that the
front/rear bias is correct even without ABS. Only the low-end crap uses
ABS as a hack-job approximation to brake balance.
Threshold braking is a lost art. I currently don't own a vehicle with
ABS. The last vehicle I had with ABS spent the last 8 years of its
existence with the ABS fuses (controller and pump) removed and with the
warning light bulb removed. It stopped rather better than it did with
ABS, and a LOT better than it did when the abs started throwing error codes.
In 45 years of driving, I have _never_ been in a situation where I needed
antilock brakes. How do I know? Because I haven't slid into anything before
having AL brakes on my Jeep, and not since I got that have I been in a
situation where the AL brakes engaged in a situation that would otherwise have
produced a crash.
I _DID_, however, become a passenger in my own car that _SLID_ out into an
intersection from a gravel road that caused the AL brakes to work extremely
poorly, and allow the car to roll into the intersection, where a regular set of
brakes would have stopped easily well in advance of the intersection, but
caught my driver by complete surprise. If the other driver at that intersction
at the time hadn't been paying attention, my AL brakes would have gotten us
Repeal absolutely ALL laws that REQUIRE that there be a particular "safety
device" on cars and simply make laws that make them available. I then will not
have to buy air bags, AL brakes, traction control, etc. etc., my car will cost
a _lot_ less, and I won't have the weight of these historically useless items
dragging down my fuel economy for the next 10 years of my ownership of the car
in question, which is how long I have to own one now because they are so
friggin' expensive... due in part to all those useless things that are mandated
by law, against my will, and that I have to buy anyway.
Good for you. Your experience does not mirror every other driver's
experience though, especially those that drive on icy and snowy roads. That
is where the new braking system does its best work. When I was 16 and just
started todrive, I had one experience with sliding on a snow covered road.
I learned from it. Some drivers never do.
Sounds like a driver that lacked a bit of experience and was travelling to
fast for conditions. Chances are the car would have slid into the
intersection anyway, but the fact is, neither of us can prove what would
have happened with regular brakes. One bit feature of AL brking sysems is
steering control. With wheels locked, you have none.
If the other driver at that intersction
If your driver had been paying attention, the situation would now have
occurred in the first place. .
AGREE heartedly with Ed on this one. For the
average driver, ABS is a godsend in maintaining
control while quickly reducing vehicle energy.
And, insurance rates seem to support this thinking.
Agree also that under competitive driving
conditions a well trained driver with heightened
reactions can probably do better without ESC or
ABS. That ability is probably good for a couple
of hours at the wheel. But, at the end of a
driving day, with twilight conditions and a
longer complex reaction time, ABS can be a winner.
A downside is the tread damage that results from
the staccato/machine-gun brake application one
gets from ABS. After an aggressive ABS
'incident' it's a good idea to at least rotate
tires or consider replacing them. Unless one
does that, a set of brake discs will soon need
I started driving in NW Ohio, where there was a lot of ice and snow from 1963 -
1983 when I left for... central Indiana where there was still some ice and
I've slid on a lot of snow-covered roads. Its inevitable, even with AL
braking. Stuff happens, and black ice rules, period.
Most memorable _not_ sliding was coming back from working a road rally in
Michigan, and encountering some fairly pretty, fairly smooth, fairly deadly ice
all over a really long bridge on I-475 around Toledo. Saw what was coming,
lined the car up to enter the bridge straight-on, pushed the clutch in, and
coasted all the way across it. But AL brakes or not, you're going for a ride
if you attempt to change anything about your speed or direction on such a
He's very experienced, and _any_ speed on gravel with that car and it's AL
brakes is "too fast for conditions." The best way to stop on gravel is to
"lock 'em up." Its a fact. AL brakes make things _worse_ on gravel, not
Absolutely not. I have _lots_ of experience with gravel driving, and any
normally-braked car would have stoped probably something like 15 ft short of
the intersection with a maximum stop.
But it isn't hard to prove that a normally-braked car will out-stop an AL
braked car severely on gravel.
Yeah, if you're boneheaded enough to hold the brake all the way down and not
let the wheels turn, you have no control. Release them a bit, and you can
steer - IOW, pump the brakes.
The situations where the difference between this method and the AL braking
method meaning the difference between a crash and no crash are extremely rare.
Most of the stuff you were going to hit with a regular braked car, you'll hit
anyway with an AL braked car. Most of the stuff you were not going to hit with
an AL braked car, you're not going to hit with a normally braked car anyway.
The only real difference is knowing enough not to go sliding off into the weeds
if you try to brake to the max - if you're experienced, you can do it. If
you're not, you _might_ not slide into the weed in an AL braked car, whereas
you would with a normally braked car.
Thats why I can be just as safe in either car, and don't need to be paying
extra $$$ for the extra equipment that is also just something else to break
down and need repair.
He was paying attention just fine - there was just no way to drive that thing
on gravel reasonbly and expect to be safe, other than maybe pulling the wire
for the AL brakes. That was a '93 Jeep Cherokee. My 98 Jeep Cherokee seems to
do a little better, but is also kind of scary. The Subaru WRX does a lot
better, although on gravel, I would still rather not have the AL.
We did an off road test with some Jeep TJ's with ABS after the first one
following the old CJ7's and YJ's over a ravine top and down the other
side had a losing argument with this tree you had to stop to avoid
before a turn. The TJ owner just couldn't stop, his wheels wouldn't
lock and he calmly just rammed the tree.
So the damage was done and he was convinced to try again. This time
with the ABS fuses out. Well no surprise, he had no trouble at all
stopping before the tree.
So he was a real good sport and as curious as we were so he put the
fuses back in and tried again. Well, once again he calmly rolled into
the tree, there was just no way to stop.
Note: If this tree hadn't been there, it was a sheer drop...
We have since done many more downhill dirt tests like that and now I
always recommend if you plan on following me in my old CJ7 off road, you
need to pull some fuses....
Thankfully my 2000 Cherokee doesn't have ABS, that might have been a
86/00 CJ7 Laredo, 33x9.5 BFG AT's, 'glass nose to tail in '00
2000 Cherokee Sport
'New' frame and everything else in '09. Some Canadian Bush Trip and
Build Photos: http://mikeromainjeeptrips.shutterfly.com
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