I’m mostly thinking about a scenario where you are going down a highway (say, at 120kmh for the sake of the example) and suddenly your brakes fail
could shifting to Reverse function as a brake in that situation?
edit: thank you all for the answers, I want to note that I myself don’t drive and did not consider doing this, I was just wondering if this was possible
have a lovely day o/
In: 11
If you have a manual transmission you just need to stop applying gas and have the current great engaging and the engine works like a break. https://en.wikipedia.org/wiki/Engine_braking It worked fine for a four-stroke gasoline engine and for some diesel engines. I have no idea how it works with an automatic gearbox.
Shifting down will increase the force needed to drive the engine around because the RPM increase. Shifting down to a to low gear will get the RPM to high and it can damage the engine. So just shift down so the RPM are keeptreasonable.
Shifting to reverse is a bad idea because it will force the engine to go on the other direction. There will be a lot of force on the engine and clutch and gearbox when you do that. It might be the case that the image gets damaged if it is go in the reverse. But even if there is no damage you end up with practically the same RPM as if you had first gear and you risk damaging the engine so just avoid it.
No you can not shift into reverse to stop the vehicle, pretty much every single vehicle on the road is going to have some sort of a fail safe to keep you from doing so because it would simply destroy the transmission and provide 0 benefit in any situation. The reasoning is because it would just sheer the teeth right off the gears because the wheels would be trying to go from 120km/h in one direction to the opposite direction instantly.
Now the scary part is no one here gave good advice in what one should do in a situation like this. Now surprisingly manual or automatic, the procedure is essentially the same (although a manual has a few more steps). In an manual transmission you shift down from 5->4->3->2->1 with 0 input on the throttle. The centripetal force of the engine spinning without the assistance of the throttle works as a braking system (not nearly as good as regular brakes). It’s simply called engine braking and something people that drive a manual transmission often do to conserve their brakes. Now in an automatic transmission you don’t have the same level of control because the transmission does its own shifting, but this also makes it a bit easier. As soon as you realize your brakes are not working you can take your gear shifter and shift it into L (for low) or 1 depending on how your transmission is labeled. This will have a similar effect of downshifting like a manual transmission, except it will go from gear to gear on its own as your speed is reduced to not cause damage to the vehicle and work as intended. A lot of people don’t understand that an automatic transmission is still capable of this. Doing this will greatly reduce your speed and could save your life.
The other important thing to do is to apply your emergency/parking brake, hence why it’s named the “emergency brake”. Now it’s important to note that this brake does not share the same safety features of your standard brakes. If you apply this brake 100% your vehicle is likely to skid and increase the odds of getting in an accident. You want to gently apply the emergency brakes and keep applying pressure making sure you don’t make the tires chirp. If you act quickly doing both of these things you can bring your vehicle to a stop in a short distance and safely. It could be what saves your life.
Just in the spirit of ELI5: When talking about the engine braking I’ll explain it a little more so it may makes sense how it works better. We all know that an engine uses fuel to make it function, the fuel is the energy used to make the pistons go up and down and the crankshaft spin which spins the transmission which spins the tires. Now lets say you are cruising in your vehicle and are doing 100 km/h with the engine spinning at 4,000 RPMS (revolutions per minute), which you normally wouldn’t do but its a theoretical for this example. Now if you were to stop providing fuel and air to the engine through the throttle, the engine wouldn’t simply stop spinning immediately. What would happen though is instead of the engine providing thrust to the transmission spinning the tires, it would work like an anchor and the energy to spin the engine would come from the vehicle’s motion forward. This is going to cause the vehicle to slow down because the forward momentum is being sapped by the spinning of the engine without the use of fuel.
No you can not shift into reverse to stop the vehicle, pretty much every single vehicle on the road is going to have some sort of a fail safe to keep you from doing so because it would simply destroy the transmission and provide 0 benefit in any situation. The reasoning is because it would just sheer the teeth right off the gears because the wheels would be trying to go from 120km/h in one direction to the opposite direction instantly.
Now the scary part is no one here gave good advice in what one should do in a situation like this. Now surprisingly manual or automatic, the procedure is essentially the same (although a manual has a few more steps). In an manual transmission you shift down from 5->4->3->2->1 with 0 input on the throttle. The centripetal force of the engine spinning without the assistance of the throttle works as a braking system (not nearly as good as regular brakes). It’s simply called engine braking and something people that drive a manual transmission often do to conserve their brakes. Now in an automatic transmission you don’t have the same level of control because the transmission does its own shifting, but this also makes it a bit easier. As soon as you realize your brakes are not working you can take your gear shifter and shift it into L (for low) or 1 depending on how your transmission is labeled. This will have a similar effect of downshifting like a manual transmission, except it will go from gear to gear on its own as your speed is reduced to not cause damage to the vehicle and work as intended. A lot of people don’t understand that an automatic transmission is still capable of this. Doing this will greatly reduce your speed and could save your life.
The other important thing to do is to apply your emergency/parking brake, hence why it’s named the “emergency brake”. Now it’s important to note that this brake does not share the same safety features of your standard brakes. If you apply this brake 100% your vehicle is likely to skid and increase the odds of getting in an accident. You want to gently apply the emergency brakes and keep applying pressure making sure you don’t make the tires chirp. If you act quickly doing both of these things you can bring your vehicle to a stop in a short distance and safely. It could be what saves your life.
Just in the spirit of ELI5: When talking about the engine braking I’ll explain it a little more so it may makes sense how it works better. We all know that an engine uses fuel to make it function, the fuel is the energy used to make the pistons go up and down and the crankshaft spin which spins the transmission which spins the tires. Now lets say you are cruising in your vehicle and are doing 100 km/h with the engine spinning at 4,000 RPMS (revolutions per minute), which you normally wouldn’t do but its a theoretical for this example. Now if you were to stop providing fuel and air to the engine through the throttle, the engine wouldn’t simply stop spinning immediately. What would happen though is instead of the engine providing thrust to the transmission spinning the tires, it would work like an anchor and the energy to spin the engine would come from the vehicle’s motion forward. This is going to cause the vehicle to slow down because the forward momentum is being sapped by the spinning of the engine without the use of fuel.
No you can not shift into reverse to stop the vehicle, pretty much every single vehicle on the road is going to have some sort of a fail safe to keep you from doing so because it would simply destroy the transmission and provide 0 benefit in any situation. The reasoning is because it would just sheer the teeth right off the gears because the wheels would be trying to go from 120km/h in one direction to the opposite direction instantly.
Now the scary part is no one here gave good advice in what one should do in a situation like this. Now surprisingly manual or automatic, the procedure is essentially the same (although a manual has a few more steps). In an manual transmission you shift down from 5->4->3->2->1 with 0 input on the throttle. The centripetal force of the engine spinning without the assistance of the throttle works as a braking system (not nearly as good as regular brakes). It’s simply called engine braking and something people that drive a manual transmission often do to conserve their brakes. Now in an automatic transmission you don’t have the same level of control because the transmission does its own shifting, but this also makes it a bit easier. As soon as you realize your brakes are not working you can take your gear shifter and shift it into L (for low) or 1 depending on how your transmission is labeled. This will have a similar effect of downshifting like a manual transmission, except it will go from gear to gear on its own as your speed is reduced to not cause damage to the vehicle and work as intended. A lot of people don’t understand that an automatic transmission is still capable of this. Doing this will greatly reduce your speed and could save your life.
The other important thing to do is to apply your emergency/parking brake, hence why it’s named the “emergency brake”. Now it’s important to note that this brake does not share the same safety features of your standard brakes. If you apply this brake 100% your vehicle is likely to skid and increase the odds of getting in an accident. You want to gently apply the emergency brakes and keep applying pressure making sure you don’t make the tires chirp. If you act quickly doing both of these things you can bring your vehicle to a stop in a short distance and safely. It could be what saves your life.
Just in the spirit of ELI5: When talking about the engine braking I’ll explain it a little more so it may makes sense how it works better. We all know that an engine uses fuel to make it function, the fuel is the energy used to make the pistons go up and down and the crankshaft spin which spins the transmission which spins the tires. Now lets say you are cruising in your vehicle and are doing 100 km/h with the engine spinning at 4,000 RPMS (revolutions per minute), which you normally wouldn’t do but its a theoretical for this example. Now if you were to stop providing fuel and air to the engine through the throttle, the engine wouldn’t simply stop spinning immediately. What would happen though is instead of the engine providing thrust to the transmission spinning the tires, it would work like an anchor and the energy to spin the engine would come from the vehicle’s motion forward. This is going to cause the vehicle to slow down because the forward momentum is being sapped by the spinning of the engine without the use of fuel.
No it would just break something if it doesn’t have an interlock to prevent you from doing it in the first place.
If you have a manual transmission, start by downshifting and taking your foot off the throttle, progress down through the gears and then pull over and shut the engine off when you get down to first gear, then pull parking brake/emergency brake.
If you have an automatic, put it in 2, or whatever the lowest gear you can get it to shift into and then when the drag of the engine doesn’t slow you any more, find an uphill slope, turn the engine off, then pull the emergency brake and put it in park the instant you’re stopped.
No it would just break something if it doesn’t have an interlock to prevent you from doing it in the first place.
If you have a manual transmission, start by downshifting and taking your foot off the throttle, progress down through the gears and then pull over and shut the engine off when you get down to first gear, then pull parking brake/emergency brake.
If you have an automatic, put it in 2, or whatever the lowest gear you can get it to shift into and then when the drag of the engine doesn’t slow you any more, find an uphill slope, turn the engine off, then pull the emergency brake and put it in park the instant you’re stopped.
No it would just break something if it doesn’t have an interlock to prevent you from doing it in the first place.
If you have a manual transmission, start by downshifting and taking your foot off the throttle, progress down through the gears and then pull over and shut the engine off when you get down to first gear, then pull parking brake/emergency brake.
If you have an automatic, put it in 2, or whatever the lowest gear you can get it to shift into and then when the drag of the engine doesn’t slow you any more, find an uphill slope, turn the engine off, then pull the emergency brake and put it in park the instant you’re stopped.
I asked myself this question when Toyotas were allegedly speeding up on their own and crashing. Interesting answers.
https://abcnews.go.com/Blotter/toyota-pay-12b-hiding-deadly-unintended-acceleration/story?id=22972214
I’ve had this happening to me, driving my trusty (turns out: not so much) old Fiat 850 towards a busy intersection. Best I could think of, was shifting to the lowest gear, from 4 to 1 in one go. It worked somewhat, the car stalled about 2 car lengths on to te intersection. I definitely scared the living daylights out of the rest of the traffic, not to mention myself and my mother, sitting next to me. The noises coming from the car! I was sure I’d ruined it, but I guess we were lucky. It started right up, and after some time, when the brakes had cooled down, I was able to coast home.
I asked myself this question when Toyotas were allegedly speeding up on their own and crashing. Interesting answers.
https://abcnews.go.com/Blotter/toyota-pay-12b-hiding-deadly-unintended-acceleration/story?id=22972214
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