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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"...


44

This is one of those things which are easier said than done. To start with, let me show you a picture of a four speed transmission which has been blown apart: All of those hundreds of parts go through the front end of the transmission. If a single part is bad (which it usually is not the case), you have to pull all of this apart in order to diagnose and ...


38

It depends on the specific vehicle. Many modern standard transmission cars in the US have a clutch pedal sensor that will not allow you to start the vehicle if the pedal isn't fully depressed. You'll turn the key and nothing will happen. I've had older vehicles that preceded this sensor that could move the vehicle if the clutch was engaged and the ...


34

This is something that used to be quite common - in the '60s and '70s, people would add an electronic (or manual) overdrive to the back of the 4-speed gearbox to give an extra gear (usually two, as it would operate in both 3rd and 4th, although on many cars the difference between overdrive-3rd and direct-4th was very little). It's unlikely to be possible on ...


30

Two of the useful features of this setup (I have no evidence to prove they were the design reasons) are: when braking in a hurry stamping down until you reach the bottom will leave you in first, NOT neutral. This is much safer in many respects than being left with no power in an emergency situation. when starting from neutral, there is no risk of ending up ...


29

Most of the time you won't need heavy braking in traffic. You can avoid stopping and starting by: Driving more calmly Leaving plenty of distance between you and the vehicle in front (even at low speed) Simply taking your foot of the accelerator early If you let the car slow down, and use the gear until it is no longer appropriate (too slow that the engine ...


28

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).


26

Answer The technical reason that manufacturers have chosen to use a sequential shift pattern with their gearbox configurations is that a standard shift plate that allows the selection of any gear desired is too bulky to fit into modern motorcycles. The REAL REASON this configuration is used is that it's defined in the US Code of Federal regulations under ...


25

Being from Canada, I feel compelled to mention that if you do not depress the clutch while starting when it is at all cold out (let's say < 0 Celsius) you will notice the starter motor labouring significantly as it spins both the cold engine and the cold transmission. If it is really cold, your battery may not have enough power to start the car at all in ...


22

tl;dr: different gear ratios are a feature, not a bug. Some cars use more gears for acceleration, some use them for better gas mileage. You can't do both. At 3300-3500 RPMs, shouldn't the WRX be able to achieve better gas mileage by keeping the same 5-speed gear ratios, while adding an additional gear to lower RPMs to 2800-3000? You've exposed the ...


22

First of all you're not smelling CO (carbon monoxide) as that is an odorless and colorless gas. What you are likely smelling are combustion byproducts and that is not at all uncommon in the engine oil. The transmission oil is another story and I suspect you are just smelling the oil itself. The thing I'd be concerned about is a sharp "burnt" smell that ...


19

For general driving, you can leave the car in drive. It doesn't damage the transmission leaving it in drive while stationary at the lights - although you don't want to be doing silly things like revving the engine while holding the brakes on. In an automatic car, you don't really use neutral. It is a step on the way to selecting Park, which means that the ...


16

To my understanding, no. I've never seen this behavior before in any auto I've ever driven or read about. I think it would be a safety issue if it did. If you needed to move suddenly (for whatever reason), pulled your foot off the brake pedal expecting the car to move, and it does nothing but rev the engine at you. This could be extremely dangerous on an ...


16

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'...


16

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 ...


15

First, everyone who said that the braking effect comes from the compression stroke is wrong...the air in the cylinder is compressed which takes energy, yet after top dead center acts as a spring and helps force the piston back down, returning the exact same force as was put into it in the first place. Probably more, actually, since the compression heats the ...


14

The main purpose of neutral on an automatic is for towing or pushing the car. Obviously you can't push it with the transmission in park, and if you tow it with the transmission in gear or in park and the drive wheels are in contact with the ground, you'll ruin your transmission or your tires or both. I'm sure there are some other uses too, but they're ...


14

They will probably work out to be the same. An automatic transmission is inherently more complicated which means more can go wrong and usually does (more so than manuals). The increased complexity also makes them more expensive, heavier, less fuel efficient etc. A manual transmission is less complicated which means there is less that can go wrong. Through ...


14

The torque converter picks up the slack In essence, this device connects the engine crankshaft to the transmission's input shaft through a fluid-type coupling. Once the turbine spins fast enough relative to the pump, the pump will start turning as well. Since the turbine and pump are not mechanically coupled the gear ratio between the engine and ...


14

The main reason slack is needed is the rear suspension of the bike. In a "perfect" setup, the axis of the rear swing-arm and the final drive of the engine would be one and the same. This is not normally possible so a compromise must be made. In this diagram, you can see the two different axis. Because of this, on a typical street bike, the chain has more ...


13

It's not something I've ever attempted, but I know people who have... The innards involve a lot of small springs, shims, etc (mainly in the synchros), and these can often have a habit of flying off when released! It is something that should only be attempted in a decent, clean workshop/garage so you can keep track of all the bits as you take it apart, and ...


13

When the car is in D and you start the engine the hydraulic pump in the automatic transmission is not providing fluid pressure until the engine starts. This fluid pressure is used to engage clutches in the transmission to engage first gear or reverse. An automatic transmission does not have gears like a manual transmission which are physically meshed into ...


13

It's not too clear which part you're referring to, so I've annotated your image with the most likely items.


13

The answer is no because you mention being limited by your redline. Regardless of power, a certain RPM will result in a certain speed for a given gearing. Chances are the gear ratios were chosen based on the factory output of the engine. However, for other cars this may not be the case. Because of wind resistance (in many cases) a vehicle may not have ...


13

Putting the transmission into "Park" engages the "parking pawl" - essentially a metal pin that locks the output shaft of transmission (and thus the driven wheels) in place. As to why it exists - it is intended as additional roll-away protection that complements (rather than replaces) the handbrake (which, as the name implies applies actual brakes - usually ...


12

Newtons Third Law For every action, there is an equal and opposite reaction. The statement means that in every interaction, there is a pair of forces acting on the two interacting objects. The size of the forces on the first object equals the size of the force on the second object. The lateral center of gravity (CG) is above the axle as well. So you have ...


12

The somewhat longer answer is that the device that makes what you're asking possible is the torque converter. This device is a pair of curved blades setup as an impeller, and a turbine. The following cutaway pictures illustrate this setup: Here is a torque converter split in half for a better view: The way this works is explained really well by a You-Tube ...


12

The difference comes down to the driver. While automatic racing gearboxes can beat a driver when it comes to performance, for the type of vehicle you describe, a manual can perform significantly higher than an automatic if the driver knows how to use it. But then if you really wanted high acceleration you would choose a different car. Maintenance is much ...


11

It is straightforward to do this without any wear to your synchromesh, but it takes a lot of practice, especially when downshifting as you need to match revs accurately. Learning to heel and toe correctly will help you a lot here! You should never need to race the engine, as you should be using the same rev range as you would normally driving the car!


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