Chapter 7: CHANGING GEARS
It is often under hard acceleration and fast gear changes when a driver grabs the wrong gear or misses a gear, making an awful noise, creating a lot of embarrassment and potentially damaging the car.
CHANGING GEARS IN A MANUAL ("Stick Shift")
Putting your hand on top of the gear selector and stirring the pot is a technique that will surely result in many missed gear changes.
Likewise changing gears with only a finger or two just doesn't cut it as good driving.
Sometimes when down-changing from fifth in many cars a driver may inadvertently try and select reverse instead of fourth gear.
Thankfully with some cars the shift pattern will not allow reverse to be selected accidentally without returning to neutral first.
A better gear changing technique drivers can use which is applicable to daily driving is to cup the hand when changing gears, so that gears are directed into the right position.
To up-change from Neutral, turn your left hand over, cup the gear knob gently and smoothly push across and up to select first, to change to second reach across with your hand turned over, cup the gear knob using your fingers to push down, to change up again keep your hand right-way up and cup the gear knob gently and smoothly push to third using your palm, to select fourth cup your hand around and use your fingers to direct from behind as you pull down, to go from fourth to fifth gear, use the same technique as from second to third.
Using this method to up or down change gears is smooth and reliable.
CHANGING GEARS IN AN AUTO
In many smaller cars the automatic transmission has 4 forward gears and one reverse gear. The driver uses the gear selector lever to set the transmission for parking, reversing, neutral or forward gears.
This selector is equipped with a lock button on the side to avoid inadvertently selecting the wrong gear.
When parked and stationary, P for Park is selected. In this setting the transmission locks to prevent the vehicle from moving. This setting compliments the use of the park brake. The engine only be started from this position or neutral, it cannot be started in a gear.
To move from Park to select another setting, the button must be used. This safety feature helps prevent unwanted or accidental vehicle movement.
Using the button R for Reverse can be selected, though this should only be done when the vehicle is completely stopped. The driver can without using the button then select N for Neutral. Neutral disengages the transmission allowing the vehicle to be pushed or roll freely. It is not recommended to select Neutral when driving, especially not when going down hill nor under heavy braking.
Again without using the button the selector can move from Neutral to D for Drive. This position allows the forward gears to change up or down depending on the speed of the vehicle and the position of the accelerator. For example under heavy acceleration the transmission will hold the lower gear until the optimum up-shift point is reached or the driver eases off the accelerator. Under light acceleration gears will change earlier to improve economy.
In some situations the driver can without depressing the selector button change to the 2 setting. This is not just second gear but rather will allow the gears to change between first and second gear only.
This position is used for extra power when driving up steep gradients for lower speed overtaking or to provide engine braking when descending prolonged steep gradients.
The 2 setting should not be used for braking, like before entering a corner.
To prevent inadvertently selecting first gear at high speeds to change into L for Low the selector button must be used. Selecting Low holds the transmission into low gear for driving up or down very steep slopes.
When moving up from Low the selector button is not required when moving to 2, Drive or the Neutral position. The instrument panel of many cars also indicates which setting has been selected.
Some vehicles will also have a power and economy switch on the centre console. Use economy whenever possible for normal driving.
Use Power only for sporty driving or when you need more engine power, such as driving in mountainous areas, towing or to overtake another vehicle in higher speed zones.
In many modern automatics the 4th gear is often an overdrive gear, used for highway driving and/or good fuel economy.
In some vehicles there is an overdrive control switch beneath the selector lock button. During normal driving the overdrive switch should be left in the pressed-in position.
This will allow automatic gear shifting from 1st to 4th gear with the selector lever in Drive.
When quick acceleration or when going up or down long steep gradients, the overdrive button can be pressed to cancel the overdrive function.
The overdrive off indicator lamp on the instrument panel will illuminate and automatic shifting will only be performed from 1st to 3rd gear.
FREQUENTLY ASKED QUESTIONS
1. Can you go from 2nd/3rd/4th/5th gear and straight into neutral or do you have to go through them all? Can I go from 5th to 2nd/1st?
Yes it is recommended that in a modern manual transmission you can skip gears when going up or down. For example; when accelerating you can if required change-up from 1st to 3rd, though 3rd gear may labour due to low engine revs. Alternatively when approaching a corner you may change from 4th or 5th down to 2nd without using the gears in between. Care needs to be exhibited to ensure you have the right speed for the gear. Many untrained drivers have a phobia about using the brakes (thinking the brake lights are a sign of weakness) and persist in the bad habit of using the gears to slow the car down. Gears are for going, brakes for slowing. As such under brakes you can skip down gears to get the most appropriate gear for the situation, but don't use the gear selection itself to slow the car. Also be careful not to gear down from 5th to 2nd at high speed or with any lateral load on the vehicle and step off the clutch in 2nd, as the car could enter into a skid.
2. If your car is rolling down a hill in neutral and it picks up speed to say 20mph, can you skip a gear? Go directly into 2nd?
Yes you can, but why would you roll down a hill in neutral? If you must roll down a hill do so in a gear with your foot depressing the clutch. This way if the car gets up to much speed (with cold brakes) you can let off the clutch to get some retardation from the gears. Going downhill is the only time gears can be used to help retard the car as brakes used too much can overheat.
3. I heard some cars can get up to 50mph on 1st gear before needing to shift to 2nd. Does this mean that you rarely have to shift gears while driving to stay within speed limits? 50mph is more than fast enough for the city. Wouldn't you be in 1st gear most of the time and have no need to go into 2nd except maybe on the freeway.
Yes some gears can get to high speed in first gear. But you would not drive around all the time in first as the engine would be carrying high revs allot, leading to poor fuel consumption, high engine temperature, increased fluid usage and increased engine component wear. The noise in the vehicle cabin would also be tiring. If you were driving at high speed in first and stepped quickly of the accelerator the effect would unsettle the car potentially leading to a skid. If for example you were cornering with high revs in 1st gear there would be weight transfer to the rear of the vehicle (due to acceleration) and by quickly letting off the pedal, the revs would drop rapidly and the weight would transfer to the front of the vehicle leaving the rear un-weighted. In a corner this can produce a tail-slide even in a front-wheel drive car. This effect is known as Lift-Off Oversteer Skidding.
4. Does it matter if it's a 4/5/6-speed gearbox? The Corvettes have a 6-speed gearbox and the new Porsche Carrera GT has a 4-speed. What does the amount of gears have in relation to speed and acceleration. Is it better to have more?
The gearbox ratios in family cars are alot different to performance cars and racing cars. In a family car 1st gear is for driving up steep hills, driveways, towing boats up a boat ramp. 2nd/3rd/4th are for suburban driving. 5th gear is usually an overdrive gear that allows for economical motoring at freeway speeds but no greater acceleration. Therefore overtaking in 5th gear is not recommended as it takes longer and increases the risk of a head on collision. In a Porsche or similar performance cars the gear ratios are slightly different. In a performance car with a 6 speed gearbox, 5th gear is also used for acceleration. In many forms of motorsport the gear ratios and diff ratios are set for each track depending on its layout. The aim is to keep the race car in the meaty part of the torque curve to allow better performance. With most family cars a driver redlining each gear to achieve maximum acceleration is a fool. Best acceleration would be achieved by changing gears at the engine revs just past the maximum torque is achieved, depending on the next gear ratio. Drivers over-revving simply make more noise, wear more components and waste more fuel without achieving a performance gain.
5. When making sudden stops, should you be concerned about putting it into neutral so the car doesn't stall? Like if you're driving and someone jumps in front of you out of no where, should you worry about slamming on the brakes and stalling? I would think in those cases, you wouldn't have enough time to hit the clutch, brake and put it in to neutral.
In a modern car with an electronic fuel injected engine and equipped with a catalytic converter in the exhaust system, when you take your foot off the accelerator does the engine revs on the tachometer drop slowly or instantly to idle? They drop slowly due to unburnt fuel being burnt and the process of the catalytic converter. Therefore in a emergency stop if you brake with no clutch depressed the engine revs and driving wheels are still connected resulting in the brakes trying to slow the car while the wheels still drive the car. Independent tests have found that braking and depressing the clutch as soon as possible can improve stopping distance by up to 10 yards at 55 mph. Don't worry about the gears, don't select neutral. But do depress the clutch.
6. If you roll down a hill in 1st gear but don't push the gas pedal or brake do you pick up speed? Say max mph for 1st gear is 15mph, will your speed accelerate pass 15mph?
How do you roll down a hill in first gear. If you park in first gear and use the park/hand brake. By letting off the park/hand brake the car will not move forward if it is in gear. Try parking your car on flat ground with it in 1st and pushing the car. It won't move.
7. When going down a hill and I don't want to go too fast, should I go down in 1st gear or neutral?
The general rule of thumb for going downhill is to use whatever gear your car needs to climb that hill. You will follow many untrained drivers down hills that have their brake lights always on. Chances are they are either driving a auto in D from dream (drive) or in too higher gear in a manual. The car wants to race away and they ride the brakes excessively. Select a lower gear so the gears help retard the car, if you need to slow, brake firmly and then come off the brakes to let them cool. Don't ride the brakes!
(Written by Joel Neilsen, Managing Director, Safe Drive Training)