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 ...


27

Bear with me, I'm going to clear up a myth, then answer your question. You will see that they are related. Higher throttle doesn't mean higher RPM. Higher throttle just means more fuel entering the combustion chamber. This will tend to accelerate your engine, but if it's under an accelerating load (increasing incline) at a constant gear, the engine will ...


23

Is it ok to give gas while releasing the clutch? Yes, but your goal is to give exactly the right amount of gas. The thing to remember is that the clutch is a consumable part (it's really a whole system of parts that can be consumed but let's pretend that it's a single unique piece for the sake of discussion). As such, it has a finite supply of work that ...


22

You can do this if your engine RPM, the speed of the vehicle, and the gear you are shifting to/from is just right. The reason you can do this is because you have synchros in the transmission which allows the two gears to match rotational speeds as they come in contact (basically, there is more to it than this, but hopefully you get the drift). The synchros ...


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 ...


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 ...


15

Heel-Toe shifting and clutchless shifting are 2 different things. I guess they can be done together.... The one thing both of these techniques have in common is rev matching. There is the RPM you are at when you come out of a gear, and the RPM you will be at when you go into the next (or previous) gear. When you rev match, you try and have the engine RPM ...


15

Reverse is pretty equivalent to first gear, for a ratio of around 3.2ish. If it were any lower, it would be difficult to get started from a stop since the torque just won't be there. If you've ever driven a stick-shift, try starting from a stop in 2nd or 3rd gear and you'll see what I mean. For example - ratios for my manual 5-speed 2007 Mazda6: 1st: 3....


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

My Volvo V70 (model year 2006) has the digital dashboard fuel consumption meter. I also have a nice, fairly long uphill climb on my way to work, so I've had opportunities to try various methods. This is a manual transmission car. According to the car, the fuel consumption is nearly the same whether I downshift from fifth to fourth gear and let off the gas ...


14

You can put your car into neutral by moving the gear selector into the position marked "N".


13

It all depends on your definition of high. In my car, the red line is at 7500 rpm, and that indicates that driving with the revs over this line for anything other than brief periods is expected to cause damage, either through overheating, increased wear, increased loading on bearings, lack of sufficient oil/fluid flow etc. When driving I have to keep my ...


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 ...


12

A lot of newer cars are smart about shifting (they have electronic solenoids to control the hydraulics). I can put my 2001 Nissan Pathfinder in reverse at 50 MPH, and it's smart enough to not engage, it goes into neutral. However, at speeds below its cutoff point (I've done it at about 15 MPH and regretted it), you can put a lot of stress on the drivetrain ...


11

I think you need to define your terms. Efficiency could mean at least four things in this context: Least fuel consumed per hour. Most mileage covered per unit of fuel. Most kinetic energy created per unit of fuel consumed. Most acceleration created per second. These four choices often destructively interfere with each other. Hitting some of the high ...


11

If your car is slowing down, and you are at a "safe" speed for 2nd gear, then its perfectly normal to skip gears. If you're going the wrong speed and the engine RPMs aren't even close to what they need to be, the syncros might have a hard time lining everything up and you could hear a little grinding, and cause a little wear, but it still shouldn't cause ...


11

Did you ever wonder why an open ended wrench is angled at exactly 15° ? That's so you can turn a nut a little bit, flip the wrench over, turn it a little bit more, and get the job done! You mentioned that you can turn the wrench 1/8th of a turn. That's plenty! In fact, I wouldn't be surprised if the mount was designed to accommodate the 15° wrench flip ...


11

The transmission has a lock up torque converter. The torque converter sits between the engine and transmission. It is kind of like a clutch on a manual transmission car. When the engine is idle, it is barely engaged, so the engine will not stall. It will engage harder and until a certain RPM. Torque converters will always have some slip in them until ...


10

It sounds like they're trying to take you for a ride to me. I can't see how driving style could cause the slave cylinder to fail - they're separated by a mechanical linkage. I would also dispute that anyone could destroy a clutch with 32k of normal driving - I'd expect it to last at least twice that long. However, a leaking cylinder might cause ...


10

This is a bad idea for several reasons. First, you run the risk of a runaway car. Second, you risk damaging your transmission, which could cause the runaway car in the first place. Thirdly, in newer fuel injected cars, you can actually get worse gas mileage. Let me explain. As stated before, by not having it in gear, you run the risk of your car getting ...


10

Background The Ducati transmission type is a constant mesh sequential. There is a ride by wire system that controls the the throttle butterfly's. Ride by wire is necessary in order for the ECU to regulate power based upon various maps the rider can select. Process The clutchless downshift is similar to the clutchless upshift in that it is essentially ...


10

It causes more wear on the clutch as you have to ride it a little more, but overall its fine. The syncros will likely wear a little faster also as the output shaft will be spinning in the opposite direction. The bigger the speed difference, the more it wears parts.


10

There are physical limits to sychronizers. When you upshift the synchronizer slows the clutch down which is relatively easy. When you down shift the synchronizer has to speed the clutch up which is much harder. Going down just a single gear is not that bad. When you're on the highway, shifting into first is not possible because you're asking the clutch to ...


9

You'll find the following will all affect your speed and acceleration: wind speed - a head wind will slow you down more than you would think your clothing - this directly impacts drag bike configuration - you'll go slower with panniers on than with them off weight - a full tank will mean you accelerate more slowly temperature - cooler air can give you a ...


9

Think of it this way. If you need to brake so incredibly hard that you're worried the automatic transmission is getting in the way, you're better off worrying about things besides whether or not you're in neutral. You're probably about to crash or lose control, so train yourself to concentrate on steering, or making sure you're arms are out of the way of ...


9

I'm going to expand on rpmerf's answer, where he has disambiguated between Heel and toe and clutchless shifting. I'l briefly explain the driving technique only to better illustrate what it hopes to mechanically achieve. And so, please excuse me if get the nuance of the technique wrong. Here's an image of a gearbox. I couldn't find a one with synchromesh, ...


9

I'm assuming you have a manual transmission. Stop doing that, you will damage your transmission. Your powertrain can be broke down into three sections. The engine, including the fly wheels. The clutch and input to the transmission. Finally the transmission output. When you push the clutch the engine is disconnected from the transmission input. When you ...


8

It depends on how you do the skipping If, when you do it, you hear loud clunks, that means you are not matching the RPM's to the road speed, to the transmission. Motorcycles have a synchronous transmission with with relatively fragile shift forks operated by a shift drum. The forks move the gears side to side to engage. if you are hearing a loud 'clack' ...


8

First, let's start by listing some facts that we know about the brakes and the engine: The brakes in a car are designed to stop the vehicle, both in emergency situations as well as under normal driving conditions. The automatic transmission in modern automobiles is optimized to keep the engine running at speeds that balance fuel economy with engine output. ...


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