Disagreement with advanced driving instructor :biglaugh:

[7mike]

Op, if you didn't agree with the instructor's recommendations why not discuss it with him (or her)? I've been a fleet trainer for fifteen years & would much rather nip in the local Starbucks to discuss rather than sit there dictating technique changes that will be forgotten tomorrow
Unless someone is specifically interested in doing a Roadcraft based advanced test or wants to improve fuel efficiency I don't particularly care how they use the gears as long as the end result is safe and works for them.

[tight fart]

The block changing I referred to was going up through the gears, we did have a good chat about
the methods discussed, and some friendly banter over a cuppa.

My view was that it takes a lot of energy to get a 3.5 tonne van going, overcoming drag, rolling resistance, drive train losses etc, why not use some of that to your advantage when trying to slow.
My brakes tend to last a long time, I’ve never had to replace a clutch (except a dmf failure) in 43 years of driving.

[Teddy Lop]

I think these kind of people "have" to find something "wrong" to justify their existence.

I remember being told by a such type lassie that indicating L3→L2 on a busy north circ was "unnecesary" as "others should anticipate it"

Yeh whatevs luv.

[hyphen]

tight fart said:

....
Second was the coasting,
Approaching lights, clear road and they change to red, we are 300m away, I would be off the throttle
Slowing gently no need to brake yet, down through the gears and anticipating the change to green.
This instructor wanted me to keep going longer, then brake whilst in gear, only dipping the clutch when the engine was starting to shudder as it was going below tick over revs.

tight fart said:

My brakes tend to last a long time, I’ve never had to replace a clutch (except a dmf failure) in 43 years of driving.

If someone else is paying for pads and disc changes, I would be using my brakes a lot more!

[Falconer]

Bigends said:

ElectricSoup said:

Bigends said:

ElectricSoup said:

Bigends said:

ecsrobin said:

tight fart said:

Approaching lights, clear road and they change to red, we are 300m away, I would be off the throttle
Slowing gently no need to brake yet, down through the gears and anticipating the change to green.
This instructor wanted me to keep going longer, then brake whilst in gear, only dipping the clutch when the engine was starting to shudder as it was going below tick over revs.

My 1 minor in my driving test was for doing exactly this.

Exactly what I was Police trained to do, though dip just prior to shudder.

Why? What's the supposed benefit?

Why change down on the approach if you know youre going to have to stop?

If lights do change on the approach, select the correct gear gear and carry on.

Thanks for answering and I'm really not trying to start an argument, I genuinely don't think that answers the question though, of what's the benefit? I'm open minded to change, so interested to know. Is it less wear and tear on gears/clutch? Is that it? Or is there a safety angle? Why is it "better" or more "advanced" technique?

Not sure, just how we were taught. I seem to recall tbe fact that brakes were cheaper than clutches was mentioned. Also 'dont select a gear unless you need it' therefore why waste effort changing down prior to stopping ?

Edited by Bigends on Wednesday 28th October 14:37

Edited by Bigends on Wednesday 28th October 16:42

I was taught “brakes are cheaper than clutches” too. In 40 years of driving , I’ve only had one clutch changed @ 170 000 miles (£500) but have spent several thousands in new brake pads and discs.

[Nurburgsingh]

OP are you actually changing down on the approach To the lights as in clutch out actively using engine braking or are you clutch in and just moving the gear lever Down through the gate?

If it’s the latter then yes, that’s coasting and no you shouldn’t do it because there is no purpose to stirring the gear lever.

[DocSteve]

Bigends said:

ElectricSoup said:

Bigends said:

ecsrobin said:

tight fart said:

Approaching lights, clear road and they change to red, we are 300m away, I would be off the throttle
Slowing gently no need to brake yet, down through the gears and anticipating the change to green.
This instructor wanted me to keep going longer, then brake whilst in gear, only dipping the clutch when the engine was starting to shudder as it was going below tick over revs.

My 1 minor in my driving test was for doing exactly this.

Exactly what I was Police trained to do, though dip just prior to shudder.

Why? What's the supposed benefit?

Why change down on the approach if you know youre going to have to stop?

If lights do change on the approach, select the correct gear gear and carry on.

I agree with this to an extent but, as with everything, it's not as clear as that. You should be in the right gear for the situation and if the situation is dynamic enough such that you may need to make use of your vehicle's correct gear to drive out of the situation. Another point I think is relevant is why brake, using pads/discs etc when a good rev-matched downshift will be mechanically better for your car. Lastly, in the alternative, if you need to show vehicles approaching behind you are slowing in good time then braking may be the better thing to do.

This is this issue with some AD instructions, they are too dogmatic

[underwhelmist]

I was always taught brakes to slow, gears to go. Brakes are cheap and transmissions are expensive. For a while I was training to be an IAM observer (motorbikes) and the guy I was observing had been told not to brake when entering a lower speed limit. Consequently he used to stuff it into a lower gear and drop the clutch to slow down without showing a brake light. I could see how it upset the bike and can imagine the effect on his clutch, chain and the rest of the drivetrain wasn't positive.

Coasting (i.e. in neutral or with the clutch held in) is pointless/daft and stirring the gears while you're doing it even more so I reckon.

tight fart said:

Approaching lights, clear road and they change to red, we are 300m away, I would be off the throttle
Slowing gently no need to brake yet, down through the gears and anticipating the change to green.
This instructor wanted me to keep going longer, then brake whilst in gear, only dipping the clutch when the engine was starting to shudder as it was going below tick over revs.

I would have used acceleration sense to slow down approaching the lights as you did, but I wouldn't have bothered changing gear until the light had changed and it was time to accelerate again. When the light changes you'll know what gear is appropriate so you can just go from 5 to 2 or whatever.

Edited by underwhelmist on Friday 30th October 01:11

[anonymous-user]

Modern engines cut the fuel injection when you go off throttle until you reach a low enough engine speed that the fuel delivety restarts to prevent it stalling.

If you want to save fuel when slowing for the lights, leave it in gear, the vehicles momentum keeps the engine turning but no fuel is going in and no torque is produced as a result.

As soon as you reach the fuel cut lower rpm point and fuel starts to flow again, selecting a lower gear will restart the fuel cut.

In practice there is very little difference between rowing down the gears and just dipping the clutch as you get to tickover speed in a higher gear, unless you are slowing from a high speed.

[Dr Jekyll]

DocSteve said:

I agree with this to an extent but, as with everything, it's not as clear as that. You should be in the right gear for the situation and if the situation is dynamic enough such that you may need to make use of your vehicle's correct gear to drive out of the situation. Another point I think is relevant is why brake, using pads/discs etc when a good rev-matched downshift will be mechanically better for your car. Lastly, in the alternative, if you need to show vehicles approaching behind you are slowing in good time then braking may be the better thing to do.

This is this issue with some AD instructions, they are too dogmatic

Some are indeed dogmatic, but another issue with instructor/student relationships generally is that instructors will often give advice relating to the specific situation in such a way that the student takes it to be a general principle. This can give a false impression of dogmatism.

[deeps]

ScoobyChris said:

ElectricSoup said:

Thanks for answering and I'm really not trying to start an argument, I genuinely don't think that answers the question though, of what's the benefit? I'm open minded to change, so interested to know. Is it less wear and tear on gears/clutch? Is that it? Or is there a safety angle? Why is it "better" or more "advanced" technique?

I guess to turn that question around what’s the benefit of dropping down through the gears on approach to the hazard

To answer your question a bit more seriously, it’s about minimising your workload dealing with hazards and so the goal is to scrub off the speed on approach (brakes) and then once the speed is right to deal with the hazard, you pick the gear for that speed and drive through and out. If you want to read up about it in more detail check out Roadcraft or The Police System Of Car Control.

Chris

The benefit of dropping down through the gears could come into play depending on what you're driving, although there maybe no benefit in a 3 ton van unless you're on snow or ice?

My GT-R has a titanium exhaust system and sounds glorious dropping down through the gears - that's reason enough sometimes

[anonymous-user]

This is my fuel cut strategy.

RPM is the value when fuel restarts on the over run, so for example above 1500rpm and 55 degrees water temp in 6th, off throttle no fuel is injected.

[Nampahc Niloc]

jsf said:

This is my fuel cut strategy.

RPM is the value when fuel restarts on the over run, so for example above 1500rpm and 55 degrees water temp in 6th, off throttle no fuel is injected.

That’s a really interesting table (to me anyway). Are these freely available for all cars?

[TheConverted]

Bigends said:

ElectricSoup said:

Bigends said:

ElectricSoup said:

Bigends said:

ecsrobin said:

tight fart said:

Approaching lights, clear road and they change to red, we are 300m away, I would be off the throttle
Slowing gently no need to brake yet, down through the gears and anticipating the change to green.
This instructor wanted me to keep going longer, then brake whilst in gear, only dipping the clutch when the engine was starting to shudder as it was going below tick over revs.

My 1 minor in my driving test was for doing exactly this.

Exactly what I was Police trained to do, though dip just prior to shudder.

Why? What's the supposed benefit?

Why change down on the approach if you know youre going to have to stop?

If lights do change on the approach, select the correct gear gear and carry on.

Thanks for answering and I'm really not trying to start an argument, I genuinely don't think that answers the question though, of what's the benefit? I'm open minded to change, so interested to know. Is it less wear and tear on gears/clutch? Is that it? Or is there a safety angle? Why is it "better" or more "advanced" technique?

Not sure, just how we were taught. I seem to recall tbe fact that brakes were cheaper than clutches was mentioned. Also 'dont select a gear unless you need it' therefore why waste effort changing down prior to stopping ?

Edited by Bigends on Wednesday 28th October 14:37

Edited by Bigends on Wednesday 28th October 16:42

im not a fleet instructor, however my understanding was that. coasting uses more fuel than keeping it in gear. modern injection systems, use less fuel on over run than they do keeping and engine running at idel.

[waremark]

TheConverted said:

im not a fleet instructor, however my understanding was that. coasting uses more fuel than keeping it in gear. modern injection systems, use less fuel on over run than they do keeping and engine running at idel.

Modern automatic gearboxes in eco mode have a coasting function where the engine idles and the drive is disconnected. In this mode there is less engine braking than with the drive connected but the foot off the throttle. If the driver takes advantage by taking his foot off the throttle earlier the fuel used to keep the engine idling is more than offset by ceasing to use fuel earlier.

[anonymous-user]

Nampahc Niloc said:

jsf said:

This is my fuel cut strategy.

RPM is the value when fuel restarts on the over run, so for example above 1500rpm and 55 degrees water temp in 6th, off throttle no fuel is injected.

That’s a really interesting table (to me anyway). Are these freely available for all cars?

That's the table from my Syvecs ECU which is a fully mapable Motorsport spec item i mapped myself, modern OEM ECU's have similar tables.

Those figures work nicely on my car, you can't feel it. By working on the cruise and overrun fuel control I reduced my fuel consumption by a huge amount, added about 100 miles to a 60 litre tank of fuel on a run.

[A1VDY]

The instructor isn't living in the real world.
My old Volvo FH 460 remapped to 500hp at 44t could not keep on the limiter on gradients on the AR's & AP'S, instead I was changing down through the I shift box, sometimes four gears.
Malaga to Calais return wasn't possible within the weekly driving hours, instead I was changing cards to my missus' card 200km South of Madrid.
In comes the Volvo FH 16 (16litre 700hp 4x2) this has enough torque to turn the world on its axis (Well, not quite) but would pull relentlessly and would hold top gear on long gradients at 100kph at 44tonne ++. I once pulled a Krone tilt loaded with 41tonnes of cast Street furniture back to Malaga grossing 56 tonnes (12t overweight) again on the limiter on the gradients in top gear.
I was back well within my own driving hours.
Fuel consumption was a little more than the 13litre 460hp version but...the time saved more than made up for 50 litres of extra fuel.
Piss about trying to save fuel is literally a waste of valuable time..

[RacerMike]

Unfortunately, most of the info that the Police and IAM training is based on is 50 plus years old. We had IAM style training at work as part of our advanced driver assessment (we're test and development drivers) for road driving. The guys are ex-Police and absolutely everything they said about road positioning, overtaking and use of speed etc was bang on. But none of us have ever agreed with them about the gear shifting.

When challenged, they can only quote what it says in the training guides, and you find that's the case for most people who do IAM or Police training. The comments of 'you'll wear the gearbox out' have no basis in reality at all. Modern cars are heavily abuse tested, and changing down gears is not considered an abuse case. It's normal. As hinted by a few others, you won't 'wear' your gearbox out by changing down, and unless you're heavily slipping the clutch on down changes, you won't be wearing that out any time soon either.

Fundamentally, what the OP is doing is absolutely fine. It's not 'bad' technique at all.....it just disagrees with what's written in a training manual based on driving a Ford Anglia with drum brakes and a gearbox that would struggle to last 30,000 miles of normal driving.There is absolutely no difference in changing at the last minute to the 'correct' gear and down changing sequentially to that point unless it genuinely takes 500% of your concentration to operate your left arm and left foot simultaneously.....in which case you shouldn't be driving a car. I'd strongly argue that down changing through the gears means you're always in the correct gear for that speed, and hence will be able to react far more quickly to unexpected situations. I find leaving shifting until the last possible moment results in far more hesitation and a much less smooth driving style than just doing what comes naturally.

I don't think the IAM and Police techniques are wrong....I just think their inability to understand how other techniques can also be as right as their techniques means that ultimately you can make someones driving worse by forcing a technique that isn't providing any real benefit just to satisfy the words on a page.But then given the fact that a Police officers job relies on them trusting the words on a page and not questioning them, is it any surprise they would do the same when doing driver training?!

[standards]

RacerMike said:

Unfortunately, most of the info that the Police and IAM training is based on is 50 plus years old. We had IAM style training at work as part of our advanced driver assessment (we're test and development drivers) for road driving. The guys are ex-Police and absolutely everything they said about road positioning, overtaking and use of speed etc was bang on. But none of us have ever agreed with them about the gear shifting.

When challenged, they can only quote what it says in the training guides, and you find that's the case for most people who do IAM or Police training. The comments of 'you'll wear the gearbox out' have no basis in reality at all. Modern cars are heavily abuse tested, and changing down gears is not considered an abuse case. It's normal. As hinted by a few others, you won't 'wear' your gearbox out by changing down, and unless you're heavily slipping the clutch on down changes, you won't be wearing that out any time soon either.

Fundamentally, what the OP is doing is absolutely fine. It's not 'bad' technique at all.....it just disagrees with what's written in a training manual based on driving a Ford Anglia with drum brakes and a gearbox that would struggle to last 30,000 miles of normal driving.There is absolutely no difference in changing at the last minute to the 'correct' gear and down changing sequentially to that point unless it genuinely takes 500% of your concentration to operate your left arm and left foot simultaneously.....in which case you shouldn't be driving a car. I'd strongly argue that down changing through the gears means you're always in the correct gear for that speed, and hence will be able to react far more quickly to unexpected situations. I find leaving shifting until the last possible moment results in far more hesitation and a much less smooth driving style than just doing what comes naturally.

I don't think the IAM and Police techniques are wrong....I just think their inability to understand how other techniques can also be as right as their techniques means that ultimately you can make someones driving worse by forcing a technique that isn't providing any real benefit just to satisfy the words on a page.But then given the fact that a Police officers job relies on them trusting the words on a page and not questioning them, is it any surprise they would do the same when doing driver training?!

I think there are bound to be situations when having to block change might cost seconds and the changing down sequentially would then pay dividends.

Those situations probably don’t, in police driving policy, justify the drawbacks in their view. As others have pointed out it’s probably more to do with minimising tasks and allow focus on the road-for police drivers at speed in modern traffic, without the high level skills of a proven track driver. Even in my day manual cars were rare in my force-both hands on the wheel more of the time. Safety would be prioritised above speed etc.

TBF the system started in the 1930s but has evolved in many respects since. Most recent Roadcraft has only just come out-haven’t got it myself though.

Take issue with your final sentence. I did 10 years in plod and that is a ridiculous remark. Maybe it was tongue in cheek in which case I deserve a parrot.

[RacerMike]

standards said:

Take issue with your final sentence. I did 10 years in plod and that is a ridiculous remark. Maybe it was tongue in cheek in which case I deserve a parrot.

Largely tongue in cheek yes, but I do think there’s some truth in it with the older boys who we had. They actually used the phrase ‘it’s in the book so it’s not for us to question’ which I think takes a certain mindset.

I agree with what you have said. The methods taught are meant to mean that someone without any existing experience or any implied ‘talent’ can safely drive at speed. It’s somewhat frustrating at times that some instructors can’t use common sense when dealing with drivers who show a higher level of proficiency. I’d say you’re better to allow someone to do whatever is the most natural thing, providing that isn’t flying in the face of safety or vehicle handling!

Edited by RacerMike on Wednesday 20th January 22:01