Which gear should an automatic transmission car hang in when waiting for a red light?

Automatic transmissions, continuously variable transmissions, dual-clutch transmissions, and semi-automatic transmissions (rare and negligible) can all be collectively referred to as automatic transmissions, and the specific type of transmission has to be analyzed on a case-by-case basis. Manual transmission: Needless to say, just hang the neutral gear when waiting for the red light, otherwise you will not be able to stand it with your left foot if you keep stepping on the clutch!

Automatic transmission: like BMW (all 8AT), Mercedes-Benz, Buick and most compact cars and SUVs (non-Volkswagen) use automatic transmission, the principle of automatic transmission is not studied in depth, you just need to know that when idling into the forward gear, step on the brakes Although the vehicle is stationary, there will be power output at this time. The car didn't move, where did the power output go?

In fact, it is a loss of power, which is lost in the torque converter, but this power loss has almost no effect on the transmission itself, at most it consumes more fuel than idle in neutral gear (if you have a trip computer, you can look at the difference between instantaneous fuel consumption in D gear and N gear), and similar to manual gear, you need to step on the brake with your right foot, and you will be tired for a long time. If you don't know that the torque converter is a magic horse, you can search and check it on the Internet. Conclusion:

You don't have to change gears when waiting for a red light for a short time, and you can switch to N gear when you wait for a red light for a long time, otherwise your feet will be tired and you will consume fuel! At this time, the clutch is in the state of engagement! Encyclopedia:

Including continuously variable transmission, dual clutch. Frequent switching to P gear is not good for the transmission, because it will pass through R reverse gear in the middle, and there will be a break on the transmission itself; Therefore, you can switch to N (neutral) when waiting for a red light, but not to P (Parking). In addition, the N gear is not suitable for a long time when the car is hooked, under normal circumstances, the N gear of the automatic transmission only has the necessary gear after parking and turning off the ignition, when towing, and the time to wait for the red light is OK, but if the car is parked, it is better to switch to the P gear!

Volkswagen's dual-clutch (other brands are similar), its N gear is not the same as the neutral gear of our manual transmission, and the N gear of the automatic transmission is also different, when parking and braking, it will disconnect the clutch, but it will engage the gear of the first gear, which is equivalent to the state of the manual transmission hanging a gear and stepping on the clutch. However, you don't need to worry too much about the fact that the DSG is in N gear, because even if you keep pressing the brakes in D gear, it will automatically disconnect the clutch and switch to "N" gear. When you lift the brakes, the clutch engages automatically.

To put it simply, just drive, generally the best dual-clutch car will have the autohold automatic parking function, this function must be used, D gear + automatic parking is easy to get. Summary: That's pretty much it, the rhetoric of online experts is one after another, but it's not that exaggerated.

If the vehicle does not have autohold, and you are afraid of stepping on tired, then you can switch to N (empty) gear and non-P gear when waiting for the red light. If you have the Autohold function, if you feel that the vehicle vibrates significantly (some models have a large vibration in D gear at idle), switch to N gear. If you are physically strong and have good foot strength and are not afraid of getting tired, then in order to save fuel, the automatic model should also switch to N gear, while the dual-clutch transmission does not need to switch any gears.

If you are not afraid of waste oil, vibration, or tired feet, you can wait for the red light without any switching. Last but not least, coasting in neutral gear (especially in automatic gear) is strictly forbidden while driving. <

Automatic transmission and other red lights work normally. 1.Engage D gear + apply the brake:

About 10 seconds. Automatic transmission vehicles generally have four gears, in order of P, R, N, D, and D for the forward gear. Based on the principle of infrequent gear changes, if the red light is short, about 10 seconds, then there is no need to change gears.

Just put d on the brakes. gear + handbrake: more than 30 seconds.

If the red light lasts for more than 30 seconds, the red light at some intersections in the urban area can even reach 99 seconds, it is generally recommended to hang N gear, that is, neutral gear, and then pull the handbrake, so that you can relax and rest.

p Parking is interpreted as a parking gear or parking gear, and some colloquial interpretations are "do not block gear"; The function is actually the same as the handbrake, but it is not suitable as the first way to park, because this structure is far from being as strong as imagined. The "ratchet" in the parking structure is integrated with the planetary gear set. When the gear turns, the ratchet and the wheel turn at the same time.

When the ratchet is forced to stop, the gear stops turning. That's the principle of parking. The mechanical structure that prevents the ratchet from running is the [parking pawl], which is rigidly bonded to the gearbox housing; However, the tensile strength of the shell and steel claw is not very high, and it can be strengthened to a certain extent through the geometric characteristics of the structure to achieve normal parking, but if there is an external force, it will directly affect the pawl.

The so-called "metal fatigue" refers to the uneven internal stress of the material structure, which leads to the destruction of molecular chains, resulting in micro-fractures that cannot be identified; But over time, the strength of the pawls will still decrease, and if the vehicle continues to be used, there is a high probability that visible fractures will occur. This is the impact of the wrong way of using the car on the structure of the P seat, and the rear-end collision in the P seat will be more serious; If you're lucky, maybe the pawls and ratchets are forced to separate, and the result is just a serious hit. However, if you're unlucky, the ratchet may break the pawl and vice versa.

At this point, you need to overhaul the gearbox. Therefore, p-blocks* should not be used when parking on sections of road with complex road conditions (there is a risk of rear-end collision). Vehicles equipped with automatic start-stop systems do not require special operation or even D n gears.

Because the start-stop system automatically shuts off when the vehicle is stopped, the braking system loses power when it is turned off. At this time, if the driver applies the brakes frequently, they may not be able to brake properly.

To ensure driving safety, the system will actively pull the handbrake when the engine is turned off (the electronic handbrake should be activated in conjunction with the automatic holding system). Release the brakes, you just need to press the throttle normally and the engine will start automatically. The "autohold" program is linked to the electronic parking brake system, and the vehicle equipped with this program does not need to be troubled when parking normally.

For example, stop in N gear, release the brake lever, and turn off the engine in P gear. These three steps will allow the hand brake to brake the vehicle normally without the travel load (only as a precautionary measure) and the ratchet and pawls will not interact with each other after engaging into P gear. However, this can be a bit more cumbersome, and vehicles with autohold can do it automatically.

When parked, they are geared directly and the electronic control system automatically performs the handbrake and combined movements.

The old driver said that when waiting for the red light, you can hang neutral, and then pull the handbrake up, this approach is the most reasonable, and some people do not like to pull the handbrake when hanging neutral, but it is easy to slip the car, and when the time causes the rear-end accident is also their full responsibility, so everyone must pay attention.

When the waiting time for an automatic transmission car is more than 40 seconds, you can push the N gear and pull the handbrake. If it is less than 40 seconds, it can be hung directly on the D gear. If the time is long, put the P gear, if it is not long, put it to N or shorter, then hang the D and step on the brakes and wait.

If the traffic light is indeed a little long, you can hang the P gear, if you wait a little, you can hang the N gear and step on the brakes, depending on the situation.

When you are waiting for a red light, you can do without gearing, you just need to step on the brakes, and then when the red light passes, you can step on the accelerator and go.

Theoretically, both P and N can be hung on the traffic light. The P gear is a parking gear, which is suitable for when the car needs to stay for a certain period of time. But in P gear, the wheels are locked, and in the event of a rear-end collision, damage to the gearbox is predictable.

In addition, when restarting, the gear shift must be reversed, and accidents are prone to occur in the event of an operation error. So generally speaking, most of the recommendations are to put N gear plus the handbrake.

What should I do if I don't shift gears and keep D gear? Of course, hanging D gear for a long time is not conducive to saving fuel consumption, and it will also make the gearbox work for a long time, and if the temperature is too high, it will also hurt the car. However, some people advocate that when the traffic light is short, you can choose to hang D gear and step on the brakes, so that you can move forward faster without changing gears frequently.

Especially when waiting for the signal light, it is best to put on the n gear, which is convenient for quick start and shifting, and at the same time the feet can relax a little. In addition, it is emphasized that the braking system should use neutral gear. Depending on the n-gear alone, the brakes may not stop.

N gear plus handbrake is a double safety that prevents the car from skidding forward. Finally, after stabilization, put the car in N gear.

Secondly, in the forward gear, the owner's attention is more focused and the accident is prevented at all times. Nowadays, more cars also have an auto-hold automatic start-stop function, which seems to save more time. In general, this feature is turned on by default.

When you need to stop, press the brake pad directly and the engine will stop later. If you need to start, just release the brakes and you're ready to go, so you can stay in D gear without having to change gears. Its main advantage is also energy saving and emission reduction, but the requirements for starters and batteries are higher in automobiles.

There are certain limitations to using automatic start-stop, such as on steep slopes, congested areas, and when air conditioning is required in hot weather.

All in all, there are a few things that everyone needs to keep in mind when driving, no matter what state you're in. When waiting for the traffic light, depending on the length of time, choose N or D gear.

When the automatic transmission car is waiting for the red light, you can directly release the accelerator all the time, hang neutral, so that the car can stop completely, and when the red light is over, you can directly step on the accelerator.

When parking, you should put on the P gear, which is the parking gear, to prevent you from accidentally stepping on the accelerator and causing an accident when you are parking.

If the automatic transmission car waits for a red light for 30 seconds, hang D gear and step on the brakes, and if it exceeds 1 minute, hang N gear and pull the handbrake.

First of all, look at the length of the traffic light, within 30 seconds, it is recommended to hang D gear, pull the handbrake, for the braking system, such as Mercedes-Benz BMW and other series have an automatic parking system, you can start the parking by stepping on the brake. After waiting for the green light, just press the gas pedal to move forward. If the traffic light time is relatively long, it is okay to stop in N gear and pull the handbrake.

When parking, pull the handbrake first and then engage the P gear, which allows the handbrake to bear most of the impact force and reduce the damage to the gearbox, especially the P gear. When the automatic transmission is engaged in P gear, the parking gear and stop claw snap together. Unlike the precision gears of other gears, these two don't bite so tightly, so the brakes are released after the P gear is hung, and the car sometimes shakes a little.

Stepping on the brakes in D gear, the power has always been in a connected state, has always been in a load state, the car shakes more violently, and the fuel consumption is also greater than N gear and P gear, and the driver's feet are also more tired and can not rest. Of course, if the red light time is only a few seconds left, and the time is very short, it is appropriate to step on the brakes in D gear, reducing a gear and reducing the impact on the gearbox.

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In your case, I think it still depends on the traffic light, the time is less than 1 minute, the D gear brake, and the N-gear handbrake is more than 1 minute!

It's normal to drive every day and wait for a traffic light. When waiting for the red light, the manual transmission car generally hangs neutral gear and then pulls the handbrake. However, there is no standard answer as to what gear an automatic transmission car hangs in while waiting for a traffic light.

What gear should a car with an automatic transmission put in while waiting for a red light?

This is a topic with no fixed answer, and it is mainly analyzed from the following situations.

1.Engage D gear and apply the brakes.

When waiting for the red light, most car owners put on D gear and stepped on the brakes. This method is relatively convenient to use in a short period of time and can be started quickly without consuming too much fuel. But waiting for a long time at a traffic light increases the load on the engine and transmission, and at the same time increases fuel consumption by a lot.

2.Hang the P file.

There are also some car owners who choose to hang in P gear and pull up the handbrake when parking. This way, they can lock the gear directly without having to keep pressing on the brakes. When the vehicle is in P gear, the locking tab snaps into the gearbox and is in a mechanical locking state.

However, if the rear end is hit at this time, the gearbox will be directly damaged, and in severe cases, the gears in the gearbox will break.

3.Hang N gear and pull the handbrake.

When the gearbox is in N gear, the gearbox and powertrain are cut off directly. At this time, the driven wheel of the torque converter in the gearbox is also in the idle state. In this case, if the drag of the main wheels in the engine decreases, the amount of fuel injected will also be reduced accordingly, and the fuel consumption will also be reduced.

However, there is a high chance that the vehicle will skid and you will need to apply the brakes or apply the handbrake.

4.Turn off the heat and pull the handbrake.

It is generally not too long to wait for a red light, and there is no need to turn off the engine. But if you are at a trunk road intersection and the red light lasts for more than a minute, you can choose to turn off the engine and pull the handbrake directly.

The automatic transmission does not have a fixed gear when waiting for the traffic light, and can be selected according to the actual situation. But when selecting gears, try not to hang on the P-gear handbrake to avoid damaging the gearbox.