You don’t think that you should be familiar enough with your own car to be able to change gears without looking at the shift lever?
All I can say is…WOW!
"Take an automatic transmission car, hold the brake pedal down as firmly as possible, and then stomp on the accelerator. The car is not going to move because the engine can’t override the torque converter. "
This is a different situation than take a car going 80 MPH. Stomp on the gas pedal and hold it to the floor. Now that the car is going 100 MPH, hold the brake pedal down and report back to us how it works out. Will it stop before the brakes overheat? That depends on the car, and if you press with full force right away, or if it takes you a few seconds to figure out that you are going to have to do full braking. It’s been tested, some cars will not stop this way, others will.
Let’s see…Brakes have to exert so many foot pounds of energy to overcome the inertial energy of the 80 mph car. The 3,000 pound car has how many foot pounds of energy at 80 mph? The car’s engine can produce (say) 350 foot pounds of energy. How much more energy is in the car’s inertia than in the engine output?
If the brakes can over-power the cars inertia, couldn’t it over-power the output of the engine, also?
I don’t know, I haven’t tried it. I’m just saying that unless you have tried it on several different cars, then you don’t know. I’ve read of people who have tried it, and their results were that some cars could be stopped this way, and some couldn’t. Since I haven’t tried it, I have to take their word for it until you try it.
I’m skeptical that taking ones eyes off the road in an actual situation is going to seem like that great an idea.
I can’t tell you the last time I actually looked at my shifter. If you have to LOOK at the shifter to determine how to shift it…then you shouldn’t be driving…
We don?t have all the facts on what happened to the lady but here?s what I think happened.
The car started to speed up so she put her foot on the brakes, the car continued to speed up so she pressed a little harder, then a little harder until she had heated the brakes up and boiled the brake fluid by the time she was standing on the brakes she had overheated the brakes.
My opinion is subject to change with new facts.
Great video!
Everything is funny if you think about it. I have been reading all this panic, and when I read this thread, the thought popped into my head, “Aim it for the biggest tree you see.” Heh, heh. Silly, of course, but it will work, and better that tree than the kindergarten down the road.
I am told race drivers continuously think, “What will I do if (blank) happens right now?” And, as a result they are far less likely to crash if something does happen unexpectedly. I view that as part of attempting to do your best while driving.
Most of us have been discussing the stuck throttle situation. There are other situations where one cannot stop, though with the split brake system we have had for a very long time, I think it’s rare today. In many cars if you realize you can’t stop, and the engine is not full throttle, it may be appropriate to pull the car into the lowest gear for maximum engine braking on those cars which do that, to get speed as low as possible before doing things like running into a tree, or putting it in reverse or park.
I am told race drivers continuously think, “What will I do if (blank) happens right now?” And, as a result they are far less likely to crash if something does happen unexpectedly. I view that as part of attempting to do your best while driving.
The Motorcycle Safety Foundation teaches motorcyclists to do the same thing. This might be why motorcyclists are less likely than cagers to be involved in an accident.
The possible Problems with Stopping a modern car at full throttle could be two fold.
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A automatic transmission will down shift multiplying the torque fighting the brakes all the way.
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The anti-lock brakes may prevent the brake from locking up possibly causing the brakes to further overheat.
In the old days if you slammed the brakes hard enough to get the tires to lock up the car could simply skid to a stop, putting the heat friction between the tire, and road, not the brakes.
Your logic is flawed, and is contrary to actual test results.
Automatics have been the primary transmission in cars since the 70’s. This is nothing new, and the brakes are still stronger than the engine even if the transmission downshifts.
Antilock brakes do keep the wheels from locking up, but will not keep the brakes from overwhelming a racing engine. Under normal conditions, the antilock brakes only kick in when the pressure on the brakes is greater than the momentum of the vehicle and the coefficient of friction with the tires on the pavement. With the addition of a racing engine, this is just more force for the brakes to overcome before the antilocks are activated.
“Your logic is flawed, and is contrary to actual test results”.
I would be interested in the test results of stopping a car at full throttle with and without the anti lock brake system activated. I think those results would be very interesting.
My theory is, if the brakes can lock up the wheels, then the brakes will not overheat (fade) allowing the car to skid to a stop.
Could you post the link to test you were referring to?
Thanks.
Consumer Reports’ automotive engineer, Jake Fisher, test drove a Toyota Venza on a test track and simulated a throttle stuck at maximum acceleration. His tests revealed that the brakes WON’T stop a Toyota Venza under those condition; though, the brakes will SLOW the car to 20 – 30 mph when the pedal is firmly HELD down, while the engine is still pulling at maximum power.
When maximum acceleration occurred, the test showed that pumping the brakes (which could be equivalent to applying the brakes, releasing, applying, releasing, applying --which some people may have done when they experience the real thing (unexpected acceleration)) would make the brakes fade to uselessness, very quickly. When that happens, the ABS warning light comes on [why?].
See the video that americar showed a link to TWO days ago! http://blogs.consumerreports.org/cars/2009/11/toyota-recalls-38-million-cars-to-modify-gas-pedals-carpets-and-software.html
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Videos of brake test of old cars in the 60s and early 70s show the test car getting up to speed, the driver then slamming on the brakes skidding the tires to a stop.
The actual braking distance back then may had to do as much with the tires as the brakes.
Powerful brakes then meant the brakes could lockup the wheels skidding the car to a stop in a predictable if not uncontrollable long straight line.
Here is a somewhat informative demonstration showing what happens when you shift to reverse at speed. At the end of the video, they even shift the machine to park.
Get comfy first because this video is gonna make you cringe
It looks like that video confirmed what I said in the first post in this thread.
I can distinctly recall being in a friend’s '85 Corolla many years ago, when his ignitor decided to fail while we were driving on the NJ Turnpike. Before I could stop him, he threw it into Park. While I feared the destruction of his transmission, all I heard was a loud ratcheting noise. After the ignitor was replaced, the car drove normally, and the transmission worked properly for the next 6 years or so.
Based on what ok4450 stated, apparently some GM automatics can be shifted into Park at high speed. However, the video appears to indicate that this will not happen on a Crown Victoria, and I know from personal experience that this will not happen in a Corolla. This is something that must vary from one make of car to another.
Now, we know that some OLDER cars will, and some won’t, go into REVERSE or PARK, when the car is at speed. We don’t know about more modern cars because no one has done the tests --at least, not publicly. Would the auto makers tell us if they do these kinds of destructive tests? Why not?
So, a car’s transmission which is receiving maximum power input from the engine probably won’t shift into REVERSE or PARK. But, MAYBE, it will shift if the engine is turned off. Then, maybe it will go into reverse, or park, or the lower gears.
The ignition switch will NOT go into the STEERING LOCK position with the gear shift at anyplace except PARK. So, there is NO danger of turning the ignition switch OFF, and overshooting into the LOCK position. None. So, this worry, which everyone has heard voiced, is wrong!
Will the automatic transmission in 3rd, 2nd, 1st, reverse, and the IGNITION SWITCH off, drive the engine? If yes, wouldn’t the power steering and the power brakes continue to work? If this is true, the advice to, “not turn off the ignition switch”, when the engine is running away, is wrong! Right?
We can speculate all we want as to what will or will not happen when we do or do not do something, but none of us really knows until we try it. However this Toyota thing comes out, it should be a wake-up call for all of us to become a lot more familiar with our vehicles than we likely are.
One thing we can all do is to drive to some relatively secluded place, park with the engine running and the parking brake on, and then PRACTICE shifting from Drive to Neutral without looking, PRACTICE turning off the ignition without locking the steering column, and PRACTICE applying the brake firmly with the same foot we use to press down on the accelerator. If we can do only those three things, I submit that there isn’t a vehicle made that we cannot bring safely to a stop.
Just thought I would post about a test I performed on the way home tonight in regards to converter stalling, etc since some seem to think an engine can overrun the transmission with a moving mass behind it.
A converter stall test is something that should not be made a habit of and it’s something that should be performed very quickly if done at all in any form.
I live in a rural area with an 8 mile straight stretch of county highway with no traffic and I performed this test on my Lincoln, and only up to a point because I’m not going to abuse a good car.
So with the car running at the posted speed limit of 55 MPH I stomped the accelerator pedal to the floor and held it, followed instantly by stomping the brake down with the other foot. Within approx. 100-125 feet the speed dropped to about 30 MPH at which point this made me antsy and I let up.
Point here is that this is a 2 ton car with about 300 Horsepower and not only did the speed drop quickly by 25 MPH even with the accelerator pedal held to the floor, the speed did not increase even 1 MPH.
If I had wanted to flog my baby a bit more I’m sure the speed could have been brought down to a crawl or even a dead stop.
Car & Driver magazine did this test and published the results in last month’s issue, not the latest issue, but the one from last month. Anyway, they tried stopping a Toyota Camry at full throttle from 70 MPH and it stopped about 20 feet longer than normal. The souped up Roush Mustang with a 500+ horsepower engine also stopped, but it took a lot longer. The one other car they tested had a brake over-ride that cuts the throttle, so its stopping distance was unchanged. They did not disconnect the ABS on any of these cars.
Ahh, I found a link to the article:
http://www.caranddriver.com/features/09q4/how_to_deal_with_unintended_acceleration-tech_dept