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I only passed my test three years ago so my experience is reasonably modern. I was taught not to change down until I'd reached he appropriate speed for the gear.
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TU, if the Stralis is the same as the smaller Eurocargo, it's an exhaust brake, and can be switched to braking on overrun, braking with footbrake or off. The switch is on the dashboard on the Eurocargo. The old floor mounted button was a lot more controllable.
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Passed my test three and a bit years ago and was told to use the brakes to slow down and put it in the right gear for the speed. Exception was coming off motorways, have always gone 5-3-1, using the engine for braking in 3rd before dropping into 1st.
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Obviously. brakes until terminal fade, then radical gearchanges and creative fishtailing to a halt. Of course with an old fashioned slush pump auto you had a total transmission lock, called park I seem to remember, best not engaged at any speed over 4mph. Anyway if the worst came to the worst... but you could do awful damage with such a device, rip the whole transmission to pieces. At very best, wear huge canvas-and-steel flats om the rear tyres.
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I will generally brake down to the speed if reduced by limit and if traveling downhill stay in same gear just take my foot off the accelerator, the engine runs just over idle and maintains the speed.
The motor is very forgiving and can hold itself at 30mph in 5th gear.
If approaching a junction from any speed I aim to be doing 20mph by braking but will drop to 2nd gear at least 50yds away this gives enough time to stop if I can't go and enough torque to pull away if I can.
the only exception are Blind Junctions usually these have the stop signs and markings where I will be gradually braking for the last 50 yds to come to a halt at the stop markings then apply the handbrake find the bitting point check all clear and move off, or traffic lights where for the last 50yds I pray they change in my favour.
This to me gives the advantage that if someone should pull out without checking I can hit the brakes and avoid them.
I would also say that you would use your brakes more if it was a road you weren't use to
but going by the gear changing signs mentioned above, this is something I have seen you are traveling along a National speed limited single carridgeway at 60mph you approach a sharp bend with the word "SLOW" written on the road you correct your speed to say 40 or 50 ish to make the bend safely, but say you were travelling at 40 ish along the road would you slow down or since the road has national limits would you stay at that speed ?
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I discovered - in my late father's papers - a cutting from the Telegraph from, I imagine, the mid 1990s, which I reproduce here. Interesting to see that it refers to a driving style invented in 1936. Written by Paul Ripley, who was iirc a police instructor and had a regular column in the Telegraph:
When I learned to drive, motorists were taught to change down sequentially through the gearbox to lose speed on the approach to hazards. This meant that the driver had to change down through 2 or 3 gears to select the correct one, a technique still practised by millions around the world. Unfortunately it has some disadvantages, namely:
1. Unless you have a 4WD, it means you are effectively braking (via engine compression) with the two driven wheels only. (The foot-brake works on all four wheels.)
2. Changing down through the gears to lose speed can cause unnecessary mechanical wear on a number of engine and transmission components.
3. A following driver may not notice or realise that you are reducing speed, because he expects to see brake lights when a car slows. This means he has less time to react, which may in turn cause problems for vehicles travelling behind him.
4. Changing gear means you cannot keep both hands on the wheel, which is necessary for control and safety when braking firmly as the vehicle is unstable in this condition.
5. You must be able to correctly match engine speed to equivalent road speed before you select each gear. Clutch operation must be smooth, especially when letting up the clutch onto a 'dead' engine (i.e. at tickover).
These are just some of the reasons why changing down through the gears to slow down the car is no longer recommended (although as discussed last week, it is still useful in some slippery condititons, when braking may reduce tyre grip).
What is taught nowadays is to miss out the 'unnecessary' intermediate gears in most situations. The brakes are applied once, followed by a single gear chagne.
Having been taught the old way, this at first sounded strange to me, but through motivation and practice, I eventually got to grips with the new technique. In fact, it is not really new, having been used extensively by police drivers and other advanced dirving organisations for many, many years. Indeed it appeared in the Roadcraft Police Drivers Manual as early as 1936.
So how is it done? When using the Driving Plan on approach to hazards (for which the sequence is Mirror-Signal-Postion-Speed-Gear), speed should be lost by means of a single braking application or decelleration to achieve an appropriate road speed for entry to the hazard.
Only when the desired speed has been achieved is a single gear change made, selecting thegear to match the chosen road speed and to provide maximum control, balance and flexibility as you negotiate the hazard.
You will find that this requires greater levels of awareness and anticipation (no bad thing). A common error at first is failing to alow enough time and space to complete both the braking application and the gear change.
The secret is to start losing speed much earlier; this not only produces smoother, more controlled deceleration, but allows plenty of time to make an unhurried gear change before you enter the hazard.
It may well be better in certain situations to select a gear slightly earlier when approaching a doubtful traffic situation, such as a busy roundabout. In circumstances such as these, it is important to be flexible when applying the 'one gear change only' rule. As with other dirving 'rules' , sticking rigidly to the text book occasionally brings its own problems. A good driver must be flexible if safety is the prime objective.
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I've done the IAM stuff and found that using only the brakes to slow the car works well in a petrol engined car but is next to useless in diesel cars due to the lower revving engines combined with long gear ratios.
Reason being, in my Diesel car as I approach a set of lights (on Red) on a long 60mph road I will be in 5th or 6th gear, doing little more than 1,800rpm or less. Without changing gear, I'd be forced to de-clutch very early - thus losing the benfit of overrun on the fuel economy and breaking the other IAM rule - don't dip the clutch too early when slowing to a stop.
With my old petrol car, not so much of a problem - especially at lower speeds. I'd typically hold 4rd gear until nearly 60mph in my old 2.4 V70, so slowing again without changing down was not a problem. In my new 1.9 CDTI Vectra, at 60mph I'd usually be in 5th or 6th gear in the same conditions cruising at 750-1000 less RPM than the Volvo.
A combination of letting the car slow itself, gentle braking and block changing the gears (at higher speeds) seems to work best for me. As long as the engine revs don't jump up and the car continues smoothly on (no neck snapping!), I don't see the problem.
I has this same discussion with my IAM observer - a great guy but didn't really get turbo diesels - 100% petrolhead and expected you to drive diesels like the large engined petrol cars he was used to! :)
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For steep enough hills, definitely use engine braking, but to maintain speed, not slow down. I drive down Reigate Hill semi-regularly and the number of drivers (i.e. almost all) who sit on the brake pedal the whole way down amazes me.
By being on all the time, they forget they have effectively switched off their brake lights and you really need to leave a huge safety gap in front of you.
For me, engine braking seems easier in a petrol car. On the aforementioned hill, which has a 40 limit, my petrol MX-5 will happily sit in 4th with no throttle and not accelerate. My diesel Octavia still seems to want to speed up even when in 3rd. Both have 6-speed boxes.
James
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