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If you got a steel wire parking brake you won't even notice pulling it at speed on many models. (Don't try this at home ...). You can usually apply more torque

If you got a steel wire parking brake you won't even notice pulling it at speed on many models. (Don't try this at home ...). You can usually apply more torque on front wheel drive with the motor than the brake can hold since the front is heavier. Newer cars usually have some electronic parking brake that might just refuse to do its thing. And the key is not connected to a relay over the batteries usually nowadays. ABS vents can lock you out from using the main wheel brakes. Welcome to the future of drive by wire cars.

giantg2 3y ago
I hate electronic parking brakes. WTF are they good for in an emergency? I guess that's why they call them parking brakes and not emergency brakes. Are we really that lazy that we can't put on a brake manually anymore?
- hef19898 3y ago
  Because most modern car brakes are complex beats with tons of electronic wizardry. So parking brakes are using those existing electronics. Makes sense. Not that it would mean much simply being mechanical, I have a car where the parking brake mechanically enganges at the rear prop shaft. And believe, all that brake does is supporting parking if the road isn't too steep.
  - giantg2 3y ago
    What electronics would the parking brake need to share? It shouldn't need ABS/stability/traction/etc. It's just an on/off state with wither a mechanical or electronic actuator.
    - hef19898 3y ago
      And allmof that actuators include ABS, ESP and whatnot.
      - giantg2 3y ago
        The parking brake is a completely separate system (required by law to be separate I'm many cases) that is independent of the hydraulics, ABS, etc. It's literally a cable attached to a lever, or to a motor (the actuator) that applies a shoe in a drum (or in some cases a pad to a rotor).
        hef19898 3y ago
        The parking brake can also just use the rear brake calipers so. And those are attached to ESP and ABS among other things on modern cars. Using the same hardware means interfaces with the systems using said hardware. If the rear calipers are too hard to move without hydraulics, the parking brake might be a seperate system on the rear axle of a car. Those seperate systemsnso don't have the power of the main brake system, even just the one on the rear axle.
        giantg2 3y ago
        I don't think I've ever seen a car that uses the hydraulics as a parking brake. Yes, some do utilize the pads in the caliper, but they activate them via a cable, thus bypassing any ABS etc that are all involved hydraulically.
        hef19898 3y ago
        Sure, but said calipers are quote often the same the maonABS brakes use. Hence interdependecies between parking brake and normal brake systems. This dependency cannot be ignored by engineers, and if the choosen trade-off is, for reason ranging from cost over weight to reliability and beyond, an electronic parking brake, well, them that is what it is. And there seems to be something to it, as almost all new passanger cars have those today.
        giantg2 3y ago
        "And there seems to be something to it, as almost all new passanger cars have those today." That's seems to be a pretty weak argument. You're also forgetting the factor that they can charge extra for more automatic features, or that marketing determined that a significant segment may want it. So it could have little to do with better performance and more to do with positioning and money. Again, what is they interdependence you speak of? The vast majority of cars have the brake systems completely separate - hydraulic with disc/caliper for regular brakes and a cable with shoes/drum for the parking brake. There's really no reason for interdependence, and you really don't see it in the vast majority of new cars.
- rightbyte 3y ago
  Ye I dislike them too. I can never learn whether to push or pull the button without mechanical feedback from tightening a wire. It is somewhat easier to start in hills if you are bad at matching the torque. I guess that is the marketing benefit. However of the computer messes up the release you are in a bad spot if e.g. half way stuck in a ditch or whatever. Edit: If you have anti roll back braking the vehicle need to be able to engage the parking brake itself so that the fail state isn't that the car starts to roll again.
  - giantg2 3y ago
    Actually, I've had cars with manual parking brakes that had the anti roll back. So the fail state would be that the car starts to roll again. I've never had it fail though. It doesn't seem like that would be a terrible condition as you'd be back to it being a normal car and you weren't in motion anyways.
    - rightbyte 3y ago
      The vehicle starting to randomly roll backwards is quite bad as it might take a while to notice for the driver. Having a roll back protection that can fail like that is probably worse than none at all. It is quite often pedestrians walk between cars in stand still traffic. The driver might also leave the car while on hill hold, which might end badly if the parking brake can't be engaged by the computer. In my experience, features like these need to be very well thought out and seamless, otherwise they confuse and you got no idea what and why stuff happens. I mean, just having a clutch pedal makes the driver intention way more explicit. I don't think the "press the gas thinking it is the brake flipping the car on a wedge in a garage" accidents happen with manual cars at all, since a panicking driver would depress the accelerator and clutch.
      - giantg2 3y ago
        "The vehicle starting to randomly roll backwards is quite bad as it might take a while to notice for the driver." Sure, drivers might be stupid. "The driver might also leave the car while on hill hold," Sure, some drivers might be extremely stupid. I think it would be hard for the computer to figure out if the action was intended or not. Just look at ll the BS with automatic braking when trying to hook up a trailer to tow. There has to be a cutoff somewhere. If it's really a problem, then we need better driver testing is someone is really that dumb. "if the parking brake can't be engaged by the computer." Do any of them actually do this? All the ones I've seen use the regular brakes. Yes, the hill assist was started to help people in a manual on a hill and I agree that there is more intention when using a third pedal. That's the tradeoff - a system that make the physical act easier while removing intention. Yeah, not having the system might be better in some ways. This shouldn't be that dangerous because we're dealing with stopped vehicles and slow speeds. The tradeoff is stopping many newbies from rolling back into the car behind them, vs hopefully tiny number of people who are so stupid as to exit the vehicle in the 1-2 seconds that the brake is still applied. Better to get rid of that last group with stricter testing.
- chowells 3y ago
  They've never been strong enough to stop your car in an emergency if the engine is running away. Anyway, the reason they've gone electronic is to add hill assist. Let your foot off the brake and you stay in place until you hit the gas. A lot of people like that.
  - giantg2 3y ago
    The hill assist is done through hydraulic actuators of the regular brakes. Emergency brakes won't bring you to an immediate stop, but they do slow you rapidly if properly adjusted. If your engine is running away, shifting to neutral or killing it is more important.

giantg2 3y ago

I hate electronic parking brakes. WTF are they good for in an emergency? I guess that's why they call them parking brakes and not emergency brakes. Are we really that lazy that we can't put on a brake manually anymore?

hef19898 3y ago
Because most modern car brakes are complex beats with tons of electronic wizardry. So parking brakes are using those existing electronics. Makes sense. Not that it would mean much simply being mechanical, I have a car where the parking brake mechanically enganges at the rear prop shaft. And believe, all that brake does is supporting parking if the road isn't too steep.
- giantg2 3y ago
  What electronics would the parking brake need to share? It shouldn't need ABS/stability/traction/etc. It's just an on/off state with wither a mechanical or electronic actuator.
  - hef19898 3y ago
    And allmof that actuators include ABS, ESP and whatnot.
    - giantg2 3y ago
      The parking brake is a completely separate system (required by law to be separate I'm many cases) that is independent of the hydraulics, ABS, etc. It's literally a cable attached to a lever, or to a motor (the actuator) that applies a shoe in a drum (or in some cases a pad to a rotor).
      - hef19898 3y ago
        The parking brake can also just use the rear brake calipers so. And those are attached to ESP and ABS among other things on modern cars. Using the same hardware means interfaces with the systems using said hardware. If the rear calipers are too hard to move without hydraulics, the parking brake might be a seperate system on the rear axle of a car. Those seperate systemsnso don't have the power of the main brake system, even just the one on the rear axle.
        giantg2 3y ago
        I don't think I've ever seen a car that uses the hydraulics as a parking brake. Yes, some do utilize the pads in the caliper, but they activate them via a cable, thus bypassing any ABS etc that are all involved hydraulically.
        hef19898 3y ago
        Sure, but said calipers are quote often the same the maonABS brakes use. Hence interdependecies between parking brake and normal brake systems. This dependency cannot be ignored by engineers, and if the choosen trade-off is, for reason ranging from cost over weight to reliability and beyond, an electronic parking brake, well, them that is what it is. And there seems to be something to it, as almost all new passanger cars have those today.
        giantg2 3y ago
        "And there seems to be something to it, as almost all new passanger cars have those today." That's seems to be a pretty weak argument. You're also forgetting the factor that they can charge extra for more automatic features, or that marketing determined that a significant segment may want it. So it could have little to do with better performance and more to do with positioning and money. Again, what is they interdependence you speak of? The vast majority of cars have the brake systems completely separate - hydraulic with disc/caliper for regular brakes and a cable with shoes/drum for the parking brake. There's really no reason for interdependence, and you really don't see it in the vast majority of new cars.
rightbyte 3y ago
Ye I dislike them too. I can never learn whether to push or pull the button without mechanical feedback from tightening a wire. It is somewhat easier to start in hills if you are bad at matching the torque. I guess that is the marketing benefit. However of the computer messes up the release you are in a bad spot if e.g. half way stuck in a ditch or whatever. Edit: If you have anti roll back braking the vehicle need to be able to engage the parking brake itself so that the fail state isn't that the car starts to roll again.
- giantg2 3y ago
  Actually, I've had cars with manual parking brakes that had the anti roll back. So the fail state would be that the car starts to roll again. I've never had it fail though. It doesn't seem like that would be a terrible condition as you'd be back to it being a normal car and you weren't in motion anyways.
  - rightbyte 3y ago
    The vehicle starting to randomly roll backwards is quite bad as it might take a while to notice for the driver. Having a roll back protection that can fail like that is probably worse than none at all. It is quite often pedestrians walk between cars in stand still traffic. The driver might also leave the car while on hill hold, which might end badly if the parking brake can't be engaged by the computer. In my experience, features like these need to be very well thought out and seamless, otherwise they confuse and you got no idea what and why stuff happens. I mean, just having a clutch pedal makes the driver intention way more explicit. I don't think the "press the gas thinking it is the brake flipping the car on a wedge in a garage" accidents happen with manual cars at all, since a panicking driver would depress the accelerator and clutch.
    - giantg2 3y ago
      "The vehicle starting to randomly roll backwards is quite bad as it might take a while to notice for the driver." Sure, drivers might be stupid. "The driver might also leave the car while on hill hold," Sure, some drivers might be extremely stupid. I think it would be hard for the computer to figure out if the action was intended or not. Just look at ll the BS with automatic braking when trying to hook up a trailer to tow. There has to be a cutoff somewhere. If it's really a problem, then we need better driver testing is someone is really that dumb. "if the parking brake can't be engaged by the computer." Do any of them actually do this? All the ones I've seen use the regular brakes. Yes, the hill assist was started to help people in a manual on a hill and I agree that there is more intention when using a third pedal. That's the tradeoff - a system that make the physical act easier while removing intention. Yeah, not having the system might be better in some ways. This shouldn't be that dangerous because we're dealing with stopped vehicles and slow speeds. The tradeoff is stopping many newbies from rolling back into the car behind them, vs hopefully tiny number of people who are so stupid as to exit the vehicle in the 1-2 seconds that the brake is still applied. Better to get rid of that last group with stricter testing.
chowells 3y ago
They've never been strong enough to stop your car in an emergency if the engine is running away. Anyway, the reason they've gone electronic is to add hill assist. Let your foot off the brake and you stay in place until you hit the gas. A lot of people like that.
- giantg2 3y ago
  The hill assist is done through hydraulic actuators of the regular brakes. Emergency brakes won't bring you to an immediate stop, but they do slow you rapidly if properly adjusted. If your engine is running away, shifting to neutral or killing it is more important.