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It seem to me there is some logic in several of the replies here. When approaching a jucntion if visibility is good and the way looks clear I might well approach in 3rd/4th, slow down a little and then accelerate if the way is clear. If not, it's on the clutch then down into 2nd/1st as appropriate. If it's busy and I'm likely to have to give way, I tend to approach, brake gently and slip down a gear to maintain the revs. I hardly ever go from say 4th to 2nd unless I've been forced to brake fairly sharply first - it just doesn't feel right to me. Likewise, coasting just feels wrong to me and Doc's very good answer illustrates why.
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I found this to be worrying when I took my daughter out to practice. The current way of stopping at lights in whatever gear you're in doesn't seem right. It's a case of pressing the clutch early (too early) to prevent juddering if in 4th or 5th. Then if the lights change there's a scramble (for a learner) to select the correct gear for setting off. It also seems to encourage them to approach lights too fast. I found it very difficult to advise my daughter for fear of confusing her. Anyway, she passed using the new system so it must be right.
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I passed my test slightly less than a year ago and was taught not to change down through the gears. This still feels unnatural to me for the reasons outlined by terrier: you have to depress the clutch slightly early to prevent the judder or even stalling. Hence the risk of coasting slightly. The trick seems to be judging the exact moment to avoid both the judder and coasting. This is probably easier to achieve in the diesel engined cars that most driving schools now use than in the petrol cars that most people end up owning.
My best guess as to the reason for not moving down through the gears is that modern cars are better at braking than used to be the case. There's therefore less need to slow down gradually or use engine braking. Braking seems like a waste of energy to me but maybe that's because I'm still thinking like a cyclist.
I had rather a long gap between driving lessons (my earliest ones were in 1987) so quite a few of these practices, as well as the length and difficulty of the test, had changed in the intervening period.
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Tell me if i'm wrong on this one or not :
I would think that slowing down via the gears i.e. 4th into 2nd would have saved fuel as your energy is being transfered from the cars motion to the engine. By depressing the clutch early and using the brakes a lot more you are wasting energy.
Right or wrong ?
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The problem with using the gearbox to decelerate is most people use the clutch to match engine/road speed so shortening it's life.
I heard current methods of instruction had changed and the aide memoire being used was "gear up, brake down" in relation to speed changes.
Might have even read that here in a previous post.
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Yep, "gears are for going, brakes are for slowing", as the IAM and, I believe, the police say.
And anyway, brake pads come cheaper than gearboxes.
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'Brake pads come cheaper than gearboxes' Why on earth does everybody say this. I am a firm believer in engine braking providing it is used sensibly. I really cannot see that using engine braking reasonably will hasten gearbox wear. OK there will be torque reversals in the gearbox but this need not in anyway be a problem. Also the torque required to turn a 'lagging' engine is probably far lower than that which the engine can develop. Obviously heavy downchanging should be avoided along with shock loads by dropping the clutch when changing down. I think there are a lot of advanced motorists who are certainly not advanced mechanics.
My last vehicle was sold on at 171K miles having been engine braked throughout its life and I can honestly say the gearbox gave no obvious signs of wear whatsoever.
Peter Bowman (amateur mechanic and professional engineer)
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Hit nail on head Terrier - that's exactly what she does and what she now says she's been told to do. I agree with you totally, what we seem to get (even though she's now quite confident behind the wheel) is driving up to the lights/junction, quite heavy braking to slow down, coasting for a few yards and then a panic to get in the right gear if the way is clear. I just can't see how that can be right. As you say it seems to encourage several undesireable traits. I take the point about 'brakes for slowing and gears for going' but don't really think the extra wear/tear on the gearbox by adopting our method is significant and what about the extra strain on the engine by slowing down and labouring in the wrong gear. Anyway, the technical aspect aside, I don't think approaching junctions in this manner is sound since it seems to remove the need to think ahead, anticipate road conditions and select the appropriate gearing to give optimum control.
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Tested 1990. Definitely taught not to change down when coming to a stop. See the block changes thread from last week for a similar discussion.
I really struggle to see what benefit there is in whacking the engine into 2nd at 30mph putting wear on the clutch and whine on the passengers ears. I'm sure you careful Backroomers drive beautifully and would use your third (sic) foot to give the engine a few revs before engaging 2nd so as to minimise wear on the clutch/gearbox, but I don't believe that this is a realistic option for the average driver - and certainly not for a learner.
Modern brakes are efficient enough to stop the car on their own!
Posters have noted 'a panic to get in the right gear if the way is clear'. At least you only get this panic if the way is clear. Provided the lights stay red, then there is no need to panic to find the right gear to change down into.
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Just to summarise the official method circa 1990 - and I believe still current. See red light, put foot on brakes. Depress clutch at appropriate point to avoid labouring. Come to standstill with TWO hands still on wheel to maximise control. Engage handbrake, select neutral. If lights change/hazard disappears, remove left hand from wheel and change down to appropriate gear.
Personally, to avoid excess thrust bearing wear, I am inclined to select neutral at the point when I depress the clutch, and then return left hand to steering wheel. Reasoning be that if you're going to coast with the clutch depressed - as per official instructions - then you might as well coast in neutral.
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IMHO - Coasting in itself isn't a problem. The problem is knowing where it's safe to do so and where it isn't, appropriate use of gears is a huge problem for learner drivers.
To try and get this knowledge across to someone trying to pass their test is futile, therefore we get the present system which although it isn't perfect is perfectly safe if adhered to.
Personally, I coast in neutral and select the appropriate gear when I need it, cannot think of any valid reason not to.
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I think the arguement about changing down gears wears out the gearbox which is a more expensive thing to fix than replacing the brakes is a bit iffy. How many people does anyone know have ever worn out a gearbox by changing down gears? I certainly have never done so myself or know anyone who has. I see a lot of drivers who adopt the braking using only the 'brakes and no gearing' method labour their engines a lot, often resulting in big-end noises. They also struggle to find the right gear too, so often are crunching and juddering away which probably causes more wear than smooth transitions on the gears.
Do modern autoboxes follow the gears down as the speed drops under braking?
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I can see your point mapmaker (cartographer?) but driving around town how often would you be approaching a junction at or above 30mph and then be faced with slamming down into 2nd at that speed? I'd say doing that was almost as bad a practice as coasting. I tend to slow down from 30mph in, say, 3rd then its no great problem dropping down to 2nd at say 15-20mph if it looks like I'm going to need to stop. No whining, no juddering, no undue clutch wear and no problem with gearing whatever comes next, whether that is stopping in the normal manner or carrying on and picking up speed because the way is clear.
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I was taught to goes down through the gears. But this is no longer considered good form.
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Could this be the reason why very few people on the roads in the snow last week appeared able to stop without sliding about all over the place? If they were able to match engine speed to the correct gear and the road speed then they would have found it much easier to have taken the road speed off gently before finally applying brakes for the final stopping. If they are used to coasting to a halt under the control of braking alone then I can see why the conditions caused so many problems as it would have required a complete change of driving technique.
I was taught in the mid 70's and was always told that I should be in the correct gear for my road speed and that coasting was a 'no-no'. Showing how set you can get in your ways, I think I would probably have a real problem with changing to a method where I just depressed the clutch and coasted up to a red light. Therefore I can understand why to change the other way at the drop of a hat would be a bit of a challenge.
Cockle
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Volvoman. As I said, I'm sure you drive beautifully and always match your revs to your car-speed before changing gear. Most of the rest of the world cannot manage it!
I'm not certain what benefit you think you're getting through changing into second at that point, if you're going to stop? IMHO the only benefit is to Ferrodo/whoever makes and fits your clutch. As beautiful as your gear changes are, if your typical gearchange cycle is 123454321N, you are doing almost twice as many gearchanges (certainly lots more before people get too pedantic) than if you do 12345N. On the basis that (even!) your clutch WILL wear out eventually, you are making it happen sooner.
I think the issue must be one of clutch rather than 'box, but gearboxes can wear out too.
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I generally don't change down from gear to gear... it's a bit of a PITA to me and it seems pointless wearing the clutch out early. I took my test in Feb 2003 and changing down was never mentioned.
When approaching a roundabout or junction where I'll have a snap "stop or go" decision to make, I'll be in 3rd gear. That way I still have low end power to accelerate (1.9TD) but am not going to fast to stop. When braking, I'll leave the clutch out until the engine revs drop to about 1200RPM and then stick the clutch in.
When coming off a motorway, I'll change from 5th -> 3rd -> 1st, using engine braking to slow me down, except in 1st, which I don't select until the car is stationary, as it's a really low ratio and gives a helluva jolt when bringing the clutch back up, even at about 10MPH.
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Learnt in the 1970's and always downshift when slowing - then if you need to speed up (lights change, for example) then you are in the correct gear and not struggling to find the right gear.
Downshift is done smoothly by matching engine revs to transmission speed.
I must have driven a million or more miles in that time and taken several cars to 100k+ miles on original clutch and transmission - so it can't be that bad! Only clutches I've ever had to change were on a '70's Spitfire (pressure plate cracked!) and a '80 Alfasud Sprint (oil contamination).
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Well I've never actually managed to wear out a clutch on any car I've owned and my current one has 145k on the clock with it's original clutch. In any event aside from what may or may not wear out prematurely, I think being in the correct gear for your road speed means you have better control - a point well made by Cockle and Aprilia. It seems to me evident that whilst there are two schools of thought here it is NOT difficult to do this and more people than you seem to think can and do drive this way. It actually demands no special skills - it's just the way we were taught to do it. As for why I might drop down into 2nd at slow speeds, I think I've already explained that I do it because it gives an axtra feeling of control and responsiveness which seems to me safer and far more relevant to driving than worrying about which component I'm likely to be wearing out first and driving according to that.
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I still don't understand what benefit there is in changing down into lower gears as you come to a stop, I concentrated on how I do it today and noticed that the engine does not labour at all as I depress the clutch at around 1,500ish revs.
I hear what people are saying about being in the right gear if conditions change, but honestly, if the lights miraculously change back to green as I approach them then it's no problem to shift into the correct gear, that's what the amber light phase is for. Besides, often a good driver would be able to anticipate if they were about to change to green anyway, the times when I'm not able, for whatever reason, to anticipate a change *and* the lights do actually change to green are few and far between, sadly. ;-)
In my (admitedly limited) experience, the lights change so rarely that I would rather keep both hands on the wheel and maintain full control of the car whilst preventing any unecessary clutch and gearbox wear than I would faff around taking my hand off the wheel to change gears and make the stop less smooth for my passengers.
Blue
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I think it all comes down to anticipation.
Coming up to lights that have only just changed to red, I slip into neutral and coast up to them. That doesn't need the clutch, so neither clutch nor brake pad wear.
On the other hand, approaching a roundabout where it either needs rapid stop or quick getaway, it makes sense to have changed down.
It is impossible to teach this kind of thing in the short time that learners have, hence the rather arbitrary rules about 'no coasting' or 'always 54321'.
With experience, all rules are meant for breaking on ocasions - that's what experience means.
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In the scenario you portray BO there may be little or no great benefit to changing down and there are occasions when I'm approaching lights which which change to amber when I'm quite close and then I may well have to stop quickly and not have time to change down from 3rd or 4th. Surely what happens more often though is that you are required to slow down due to traffic, cars pulling out etc. and then find the way perfectly clear enough to carry on in which case being in the correct gear for your speed makes life easier.
Sure, if you've never been taught to do this it will feel strange but I'd suggest you keep trying and once you've mastered it then decide for yourself which is the best option. As I've said before I think you'll find there are some circumstances in which one method will be preferable to the other and since you'll be capable of both you'll have the best of both worlds.
Incidentally, if we're not too worried about what gear we're in when slowing down, does that apply when accelerating? Are new learners taught not to worry too much about changing up but wait until the engines's screaming it's head off before doing so ? If we're talking about wear and tear, surely that's not doing the car any good either.
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Volvoman. There appear to be three separate scenarios in your above post - and I really don't think we're disagreeing.
1. 'Are they taught not to worry when changing up' Oh yes they are! Managing the gears on the way up is the crucial skill.
2. Approaching traffic lights that are on red. 'there may be little or no great benefit to changing down'. Glad we all agree!
3. 'slow down due to traffic, cars pulling out etc. and then find the way perfectly clear enough to carry on'. This is a completely different scenario. There's no point in coasting to a stop, because you're not anticipating stopping! I absolutely agree with you - and I'm fairly sure Blue Oval will too. But I probably wouldn't choose the gear I choose until I decide what gear I'm going to need.
But in case 3, you're not using your gears to slow, you're merely dropping into the correct gear for the cirumstances/speed at that time.
We're not worried what gear we're in when we're coming to a stop, but we ARE when we're not coming to a stop. We're merely arguing that engine breaking in general driving conditions is too much like hard work and, as you say, 'there may be little or no great benefit to changing down'.
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Surely there will be times when, for example, coming to a junction or lights on a hill when it will be impossible just to slow down to a virtual stop in say 4th. In such circumstances the driver would have been taught and expected to change down through the gears to avoid stalling so I don't see how this technique can be so difficult or unusual.
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