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Can we use Neutral (N on the selector) instead of Park (P) when parking on a flat surface?

Is this useful for transmission system? Because every time we put gear on P we must pass through R and will this reduce gearbox/clutch's life?

What is the mechanical difference between Park and Neutral? I think Park is basically neutral, but with a parking pin locks the wheels from moving... so when surface is flat we don't need that pin and using handbrake is enough.

What do you think?

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    Welcome to Motor Vehicle Maintenance & Repair! – Pᴀᴜʟsᴛᴇʀ2 Nov 29 '17 at 13:41
  • thanks for your answers, but is there any problem to leave car in N in my House parking?! i know all benefits of Park gear, but i want to know using of Nature for parking will damage transmission or not. thanks... – said h Nov 29 '17 at 16:06
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    Read your car's manual. Follow the manufacturer's advice for stopping and parking your car. Manufacturers don't tend to put things into manuals that they know will damage the car. – user30078 Nov 29 '17 at 16:11
  • Do consider the fact that when you put your brakes on P (Park), the doors unlock automatically in any decently new model. It does not when you move it to N. Granted, the door unlocks when you open it, but just be mindful of the fact that all the other doors are still locked. – Crazy Cucumber Nov 30 '17 at 19:20
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    Relevant top hit on Google: reddit.com/r/NoStupidQuestions/comments/1u0un7/… . N and P are exactly as advertised/expected. And let me tell you from the perspective of someone who as once parked a bus on a hill and forgot to put the gear and handbrake in - just to find the bus having rolled backwards a few hundred meters, thank god steering itself gently off the street into a pole instead of any real damage. You don't want to try your luck. – AnoE Dec 1 '17 at 14:32

13 Answers 13

-5

You dont have to use P especially when parking on flat surface.

Minimizing shifts from N to R then to P and vice versa will minimize wears on clucth packs and brake bands

  • This answer is incorrect. Everytime you stop the engine, there won't be hydraulic pressure and it would be same as N. When you move transmission, you can just go over R and it won't engage. It takes a moment/delay after setting anyway. @motosubatsu's answer is much better. – Evren Yurtesen Nov 14 '18 at 0:35
46

Depends on the car.. some won't let you remove the key from ignition if it's not in park.

To be honest I really wouldn't worry about "crossing" reverse when heading for Park there is usually a slight delay before it engages the clutch anyway so when moving the selector you will be past it and into park before it does anything about selecting reverse.

"Park" is, as the name implies what it's designed to be put in when parking up so it's a safe bet that that's a good course of action.

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The simple answer is "No". There is no useful reason/benefit to using the transmission any other way than it was designed.

Use PARK (P).

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    This answer explains it well. For all intents and purposes, yes P is basically in neutral but has the added feature of preventing the car from moving. Therefore, it is much safer. – CharlieRB Nov 29 '17 at 16:49
  • Well, there IS a useful reason, when you park in places where there's so little space that people gently push other cars when parking and departing. It is likely not to be so gently when your car is on gear. However, this is not going to be nice for carroserie anyway, and this wil die out if people in such places would get more modern car... maybe in 20 years... – user21338 Dec 1 '17 at 9:29
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Can we use Neutral (N on the selector) instead of Park (P) when parking on a flat surface?

Possibly. Others have delved into the details already, read the other answers.

However there is one important point that I have not seen brought up yet.

Regardless of the type of transmission, you should have two mechanisms stopping your car from moving while unattended. With an automatic transmission, put the gear selector in Park, and engage the parking brake. With a manual transmission, put the gear selector in first gear (or reverse, whichever is recommended in the owner's manual) and engage the parking brake.

The goal here is to have a failsafe: systems can and do fail. Let us say you park in neutral and engage the parking brake. Now if someone cuts the physical cable (parking brake works like a bicycle brake with a steel cable to engage the brakes, and usually only the rear ones) they can roll your car away to a chop shop1, roll it into another car for "fun," whatever they want while you are not around.

What if you use only the parking gear but not the parking brake? While rare, transmissions do fail. What if the parts responsible for stopping the transmission from moving cracked and broke? Your car could roll away due to gravity or thieves. Note that even a "flat surface" does not mean "level" and what appears level might not be.

By using both mechanisms together, you mitigate the risk of your vehicle moving without you intending it to. Both systems have to fail, and at roughly the same time.

There is a third mechanism for use on hills, which is actually coded into law in some jurisdictions: curbing your car's wheels.

What is the mechanical difference between Park and Neutral?

Park engages a parking pawl inside the transmission which prevents the transmission output shaft or shafts from moving more than a tiny bit (the little bit of give is why a car might lurch a few inches after parking on an incline). Other than that, park might be equivalent to neutral, or there could be another locking mechanism. Any differences are specific to the manufacturer and model of transmission.

1 There are ways to steer cars even without the key, such as when the manufacturer does not put a steering lock in the car to begin with.

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    That's a good point. I had a manual once that had a failing ebrake cable. I was new to driving (and manuals), so I had parked on a hill using just the ebrake and without the transmission. I went back for my car later and found that my car had been "stolen." Momentary heart attack. Then I looked down the hill and found that my car had rolled about half a mile to the nearest tree in someone's yard. That was the last time I ever parked without being in first. Automatics could definitely roll away while you're not looking if you're not in Park. – phyrfox Nov 29 '17 at 21:14
  • @phyrfox I had a manual transmission where the rear brakes had worn out a bit, but I did not notice because the front ones worked fine and being drum brakes, there was no easy way to inspect them without pulling them apart. Anyway, I was stopped on a hill while I checked a map on my phone, so I put it in neutral and used the parking brake rather than holding it with the regular brake. It started sliding backwards. Luckily I was in the driver's seat with the engine running so it was an easy problem to solve, but still, I can definitely see how a car can roll with just the parking brake. – user4896 Nov 29 '17 at 22:11
  • @Snowman your "weak" parking brake was probably just not adjusted properly, driving in reverse & stopping hard should fix it (unless it was damaged or really dirty), or the cable needed adjustment. Most brakes should make horrible grinding sounds if they wear out too much. Inspecting drum brakes should be "pull off the drum" harder than inspecting front brakes (again unless damaged/filthy, and then you should really fix'em since it's good to have working brakes) – Xen2050 Nov 30 '17 at 3:11
  • @Xen2050 the weak parking brake was due to the rear drum brakes being worn all the way down, confirmed when replacing them for the first time after around 130,000 miles. Parking brake worked like a champ after that. Only reason I let it go that long is the brakes in general lasted a long time thanks to engine braking frequently, being manual transmission. – user4896 Nov 30 '17 at 3:30
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    Fun fact: in hilly San Francisco two systems are not enough, so you're obliged to engage yet another way of braking by turning wheels towards the curb. – Agent_L Nov 30 '17 at 10:17
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Because of the way an automatic transmission works, this really is a non-issue. You're probably thinking about how in a manual transmission, when you move the gear shifter, you are physically pushing and pulling different gears into place.

In an automatic transmission, it does the work for you using hydraulic pressure. When you move the gear selector, you're only opening certain fluid valves (or signaling the computer to do this), and it takes a (short) bit of time for the gears to actually move and change. If you move the selector quickly past reverse, the gears don't really have time to react. With an electronically controlled transmission, chances are nothing happens at all if you don't pause on reverse.

Also as motosubatsu mentioned, you can't remove the key unless the car is in park. This isn't something that manufactures just decided to do, it's actually a federal regulation covering vehicle safety that specifies that the key can only be removed in park to prevent rollaway and theft.

  • Well, I think mechanically you are right, but the parking pawl will hold the driven wheels in place and cannot be bypassed, whereas the emergency brake will hold the rear wheels and the cable is simple to find and quickly cut to put the car in motion (for theft or vandalism). And you can't remove the key in neutral. – JPhi1618 Nov 29 '17 at 16:44
  • Cutting the parking brake cable is a great way to get run over. Huge parts of the population never use the parking brake, particularly in the rustbelt where it rusts up in very short order. Why do an extra step when the automatic does it for you automatically? – Harper - Reinstate Monica Nov 30 '17 at 6:11
  • I don't even know where the lever for the parking brake is on my car and I haven't heard that sound for like 20y. – Mazura Dec 1 '17 at 2:59
  • Nearly all automatic transmission cars have a bypass to disengage the parking pawl without the key. Tow truck drivers, wreckers, and repossessors use this feature all the time. – cscracker Apr 23 '18 at 14:44
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Setting your car in Park does not cause wear of any kind, and most automatics I have driven will not start or let you remove the key in any other position than Park.

First of all, I'd like to point out that even if Reverse did fully engage, the wear on clutches and brake bands caused by it is about the same as each of the individual gear shifts your transmission made during your drive. You should not worry about how many times your transmission changes gears. Very heavy loads and aggressive driving are the real causes of increased wear on an automatic transmission.

Now, putting your vehicle in park will not cause any wear, because:

  • In a computer-controlled automatic transmission, the computer will only change gear if you stay in the gear for a while. Moving from Drive to Park, even relatively slowly, will not cause the transmission to even consider engaging Reverse.

  • On a fully hydraulic automatic transmission, Reverse will be engaged immediately, but this operation is so slow that if you move straight from Drive to Park in a direct motion, it simply won't have time to do anything, much less cause wear.

  • If the vehicle is turned off first, all gears will be stationary, so even if you fully engaged Reverse, there will be no wear on the clutches and brake bands of any kind.

  • The parking prawl and parking gear are quite massive chunks of steel, and their only wear is mild friction when engaging. Nothing short of intentional destructive behavior will cause noticeable wear on your parking prawl and gear.

I would also like to add that having a habit where you do not always engage park is probably a bad idea, as you risk forgetting to engage park when you really need to, instead of it being plain muscle memory. Even a well-serviced handbrake is much less capable than a parking gear, and handbrakes in automatics are usually far from well serviced (even if they're used, their reduced effectiveness is hidden by the parking gear).

Others add that engaging the handbrake prior to the parking gear may be a good idea in order to slightly reduce wear on parking gear and prawl, and ease parking gear disengagement (which can be hard when the parking gear is engaged in a vehicle on a slope). The parking gear does not engage unless the vehicle moves slightly after being put in park, so in this configuration, it will only engage if the handbrake slips. I do not do this myself, as I see no reason to worry about parking prawl/gear wear, and would rather have certainty that the vehicle cannot move.

  • in my car Reverse will be engaged immediately. – said h Dec 1 '17 at 15:34
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    Since the OP is interested in mitigating wear in parking scenarios, I'd like to add that when entering Park, I 100% always engage my parking brake before releasing the brake pedal, even on level ground. Then, when I start the vehicle, I depress the brake pedal before releasing the parking brake and shifting out of park and into gear. I'm fully convinced this prevents the vehicle from coming to rest on its transmission components and has helped extend the life of my automatic transmission. – elrobis Dec 1 '17 at 17:36
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    @elrobis I do that too, it also has the nice advantage of avoiding the lurch when releasing the brake in park. – Stephen Kitt Dec 1 '17 at 21:13
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    @elrobis I added it to the answer. It does mean that the parking gear never engages. However, the forces applied to the drive axles and output shaft when in park are much, much lower than those under even mild acceleration, and as the lock is placed on the output shaft to the transmission house, no other components see any load. The benefit here lies in reducing stress or avoiding engagement of the parking prawl, which allows easier disengagement and less risk of breakage of a hard-to-replace part, as well as reduced friction wear (which I believe is entirely negligible already). – Kenny Dec 2 '17 at 0:57
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    @saidh That seems to be a computerized automatic 4-speed transmission from the early 90's. Computerized transmissions usually wait to engage reverse, but I can't really say for sure about this one. However, as I said in the answer, it really doesn't matter. A swift Drive to Park change simply won't give it enough time to engage Reverse if it tried to (on hydraulic actuated autos, basically the lower the engine revs, the longer it takes), and even if you let it, it's just the wear of a single gear change. Don't worry about it. – Kenny Dec 4 '17 at 0:47
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Leaving car in neutral can be quite dangerous, if someone rest on your car and your car don't have hand brake engaged your car will start moving and can hit another car, get on the road or hit somebody. Gears and clutch wear when there is extreme force or heat caused by friction, which means putting car in park won't cause any damage, as long, as the car isn't moving and it's recommended to put it in park. A bit off-topic but also don't engage your car hand brake in winter because, it will freeze and can damage the hand brake cables or pads will stuck to the rotor.

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    The handbrake freezing in winter is something I see mentioned frequently - maybe it's something that happens in more extreme climates than the UK (we don't get much below -14C here) but I've literally never had it happen or heard of it happening to anyone I know. – motosubatsu Nov 29 '17 at 15:54
  • this is not matter, i want to use N just in my House Parking to reduce wear and tear of transmission, even 1% – said h Nov 29 '17 at 15:57
  • @motosubatsu this happens when u drive in rain/snow water gets between brake pads and rotor, and freeze. As you know water freeze at 0C so at -14C you have big chance to get your handbrake stuck! – AsenM Nov 29 '17 at 16:02
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    Leaving your car without the handbrake engaged is an offence in the UK. – Chenmunka Nov 29 '17 at 16:06
  • Oh no idea about the UK laws.I'm telling you about safety of your car. – AsenM Nov 29 '17 at 16:07
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The difference between neutral and park in your auto transmission is that the auto transmission has something called a parking prawl which basically physically locks your transmission gears.

https://estimate.myautomatictransmission.com/transmission-parking-pawl/

You need to put the transmission in park else the car will roll away. Even on a flat surface this is a concern because someone can just push your car out of the way.

While on the topic, you should take special care when parking on a steep hill. Do not just put it in park. This would result in high pressures on the parking prawl which will make it hard to take the tranny out of park -- because the force of the prawl holding the car on that hill. Instead, engage your parking brake and let the car rest on that, and then put it in park.

Aside from making it easier to take out of park, you also minimize the risk that using the parking prawl to support the weight of your car on a hill for extended period might physically brake the prawl.

UPDATED: In the part of the answer speaking of using the e-brake first when parking on a hill, with the regular brake applied you engage the e-brake and still in drive, then let your foot off the regular brake. This sets the weight of the car on the e-brake. Then you engage the transmission in park. You end up with both the e-brake and parking prawl together holding the car on the hill, but the majority of the force is on the e-brake.

  • is there any problem to use Natural in flat surfaces? i know using P will lock wheels, but i prefer to using handbrake. – said h Nov 29 '17 at 22:31
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    @saidh You can't possibly save enough on transmission wear and tear to cover the expenses you will incur if your car causes some damage because you parked negligently. – user3067860 Nov 30 '17 at 18:51
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Compared to non-automatic transmissions, the Neutral gear is like separating the transmission (no gear at all), whilst Park is connected transmission (usually you chose the first gear on non-automatic transmissions). With the transmission separated, the car will roll away if the ground is not perfectly flat (and be sure, there is hardly any perfectly flat ground).

Some cars have a security function that prevents the key from being pulled out if the Parking gear is not set - to prevent you from mistakenly letting your car roll away.

1

TLDR: won't make a difference. But other driving techniques will. Pursue those.

It won't reduce wear and tear. Automatic transmission wear does not work that way.

Wear in an automatic happens when clutches and bands are engaged whilst the surfaces are spinning in opposition, i.e. When shifting gears while underway. Wear and tear does not occur in the torque converter. What happens instead is heating of the hydraulic fluid, which is why there's an extra radiator inside or in front of your regular radiator to cool your transmission fluid.

If your engine is at idle, there is little wear engaging either R or D gears: at idle, the torque converter output shaft is barely moving with little force behind it, and the car is stopped, hence the engaging surfaces are barely moving against each other and they engage trivially.

In any case, the reverse gear takes a second or so to engage (and on computer controlled automatics, longer than that, as they seek to discourage people from trying to rock cars out of ruts). Simply passing through the gear briskly from D to P doesn't give the clutches/bands time to engage, and in a computer controlled transmission, the computer will decline to engage them regardless, since it sees the handle is actively in transition.

If you are keen on reducing wear, try reducing the power level at which the transmission shifts. For instance I got to know my transmission pretty well, and I knew when it was going to upshift at this throttle setting, so I'd lift off the throttle pretty much at that moment, - this input also caused the upshift, since it was defering upshift because I was on power. After the upshift, I'd reapply power, but not so much power as to make it downshift again. And of course good driving planning so I don't often have the heavy jab of power that causes a downshift, because that is the worst case scenario for clutch/band wear.

  • I found the last sentence of your post most interesting. Any idea which of these two is worse? (0) kicking the accelerator to get a down-shift (1) down-shifting by pulling the gar lever out of D, back to 3 or 2 (whichever is the highest for a particular model of car) – enhzflep Dec 1 '17 at 8:43
  • As a data point, my '06 F150 ECU automatically does this -- for an instant, it reduces engine power as the transmission upshifts. You hear an ever so slight blip in the engine when this happens but the shift is incredibly smooth as a result. Not sure if other newer vehicles may have also adopted this technique? – madscientist159 Dec 2 '17 at 7:51
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Question seems still not clearly replied. I found this topic while searching for something similar.

Question is clear. Let's sum it. Can we use N on a flat surface with hand brake?

So no rolling at all. Not asking about extreme cold can freeze handbrake. Not asking about how he should park. Not discussing over if somebody pushes the car etc. Nearly all replied just to reply.

So let's extend the worry of the question owner. What if another car will hit or push the parking car in P postion? Or a tow operator who will forcibly drag it?

Still no damage at all?

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It depends on the condition of stopping. If you are stopping while having the engine running (if you're heating the engine in the morning or when you stop at traffic light or waiting for someone), it's better to put it in Neutral with handbrake on to allow the Automatic Gear Oil to circulate properly. But if you are stopping for parking, it's better to put the gear on "Park", unless you are parking parallel on flat surface that someone might need to move your car while you're away (this is common in my country, indonesia). But again, for safety reason, i think we should avoid parking on Neutral Gear as much as possible as someone might push/move/hit our car while we park and cause the car to roll and hit someone/something (There's a lot of incidents of that in Indonesia). For several brand, you do need to put the gear into Park so you can turn off the engine properly/lock the door, but usually there's a mechanism you can park in "Neutral" (using the lock on gear or for example in my car, i have to put my carkey into a tiny lock hole next to the gear stick to shift the gear from Park to Neutral after the engine is turned off, otherwise it won't let me lock the car

0

Very bad idea for safety reasons. The best and safest method is to place the transmission in park and set the parking brake. When shifting into drive the transmission will not engage the clutches passing over reverse. Even manual transmission cars need to be left in gear with the parking brake applied when parked. You are putting yourself and others at risk if you rely only on a parking brake.

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