Gear changing in diesel car

[Helen46]

I have just started the advanced driving course. I have driven very little for many years and recently had my first ever accident when I went into the back of a car at a roundabout. I just wanted to get more confidence and also be able to manoeuvre the car better in tight spaces, eg multi-level car parks. However, the instructor is trying to make me alter my whole way of driving.

When approaching a junction or roundabout the instructor insists that I brake to about 15mph before changing gear but our diesel car doesn't like going so slowly in a high gear and judders so I have to depress the clutch. My other half says this is completely wrong and I should change gears progressively as the car slows. When I found an online forum discussing this 'block changing' which also mentioned changing up from say 2nd to 4th he said that if I ever do that in his car he's taking the keys off me and I won't be driving it again (we only have the one car). I'd hoped the course would stop these domestic arguments about my driving (he usually complains that I don't anticipate enough) but it's making it worse. My father also drives a Ford Focus diesel and agrees with my husband. Advice, please.

[GJD]

Hello Helen. Welcome to the forum. Which organisation are you doing the advanced training with? How many sessions have you had?

There's absolutely nothing wrong with block changing, up or down. I believe it's what learners are taught to do and has been for many years. It's certainly what I was taught to do as a learner and it was normal practice when I took up advanced driving. Personally, I regard the gearbox as a device put there for me to use, so if I was previously in 5th and the next gear I need is 2nd, I will change from 5th to 2nd.

However, there are more important things in driving than block vs sequential gear changing. You mentioned one of them - anticipation. Observation, anticipation and planning are essential skills for enjoyable, accident-free driving and very satisfying to develop. Perhaps you could ask your observer/tutor/instructor for their opinion on that area of your driving for now and leave details like block vs sequential gear changing until later?

[Helen46]

Thanks for your reply. I am learning with IAM.

The issue is: I have always changed gear depending on how the car feels/sounds, not the speed it is going. When accelerating, beyond a certain speed in 2nd gear I can hear the engine sound change so I change up to 3rd, 4th and so on. Likewise when slowing down the sound/feel of the car changes so I change gear. I don't often look at the speedometer except sometimes to make sure I'm not going over 30mph for instance. Previously we had petrol cars but the diesel doesn't like going slowly in high gear so by the sound it makes I want to change down to 2nd before finishing braking to 15mph, not after or I have to depress the clutch to stop it juddering. Surely then I'm not in control of the car if it isn't in gear?

Both observed sessions so far have consisted purely of practising this new brake, gear change, accelerate method.

Regarding block changing up (which I've never done, incidentally, recent threats from other half not withstanding) - surely for part of this you are in the wrong gear for your speed, eg too fast for 2nd and too slow for 4th or 5th?

[ExadiNigel]

Block changing is teh way to go, done correctly it is less wear and tear on the car, on you and will save fuel. Just because there are intermediate gears available doesn't mean you have to use them all. Different cars will need the clutch depressing at different speeds. I disagree with a particular speed being suggested as when to change down.

The speed range for the gears overlap quite a lot, they need to to suit different circumstances as you drive. Sometimes you may wish to accelerate quickly others not so. Block changing isn't something that MUST be done EVERY time. It would be your default method but not your only method.

Perhaps your father & other half should be updating their driving too? Or maybe trade the other half in for a more flexible model?

[Gareth]

For improving confidence and for help with practicing manoeuvring in tight spaces have you considered going to an ADI? I'm not sure advanced driving is really what you're looking for. One advantage of using an ADI is that you could talk to a few to find one that you get on with and who will agree to help in the areas that concern you without fundamentally changing your approach to driving, (as long as it's safe).

As GJD says, however, an advanced driving course might help more with your observation and anticipation skills than going to an ADI, (although that's not to say ADIs can't help in this area, just that most are geared up to train learners and perhaps are less interested in the finer points that advanced driving aspires to embrace).

Regarding block changing, it can be used in the way GJD mentions, as part of slowing down but it can also be used while accelerating. If you need to accelerate briskly to, say, 50 mph you might find you'd managed that in 2nd gear. At least you could in our diesel powered car, given sufficient need. At that point there would be little point in changing sequentially to the appropriate gear for maintaining that speed, (5th in our car), so block changing would make more sense. If you other half doesn't like that perhaps it is that they always drive quite slowly and only use a small amount of acceleration?

Finally a comment about your 'instructor'. If you are going to a local group affiliated with either the IAM or RoADAR then the 'instructor' will be a volunteer, well-meaning but possibly with limited experience of driving a variety of vehicles, so then it is likely they're not familiar with the constraints of your car. If your car is anything like ours, it violently objects to being in gear with the clutch engaged with the engine turning below a little over 1000 rpm. The pragmatic solution to this is an early change to a lower gear; I tend to change down to 3rd if there is a reasonable possibility I'll be needing to stop as this allows much nicer results.

[Gareth]

beyond a certain speed in 2nd gear I can hear the engine sound change so I change up to 3rd

I often tell people that changing up because the engine is loud is the least useful trigger

Regarding block changing up [...] surely for part of this you are in the wrong gear for your speed, eg too fast for 2nd and too slow for 4th or 5th?

For interests sake it might be worth finding out the maximum speed in each gear for your car. This information might be included in the handbook. If you are able to find this, you'll also find that there can be a considerable overlap between the capability of one gear and the next. This flexibility is to allow for a range of driving circumstances.

Some people use this to accelerate more briskly at times. Other times you will need it to climb a steep hill when your car is heavily laden -- I've recently been taking a learner out; they changed up to 3rd gear half way up a hill then found they needed to change back down to 2nd!


Added: on the way home this evening I noted how I use the gears ... typically I accelerate up to 3000 rpm in 1st gear before changing to 2nd at just under 20 mph. If I accelerate up to 3000 rpm in 3rd gear I can comfortably change to 5th gear.

[fungus]

Hi Helen, and welcome to the forum.

If you are doing the IAM Skills for Life, you will find quite an emphasis on block changing and separating braking and downward gear changes. A lot will depend on the observer, with some being very rigid on the matter, others less so. At the end of the day you will be taking their advanced test, and these techniques are what will be looked for.

As regards to block changing up, I personally only ever miss out one gear as I feel that the difference is too great to allow flexibility. When changing down, I found that in my last car, a 1.9 Seat Ibiza TDI the gearing was simply too high to go from fith to second, and it was often better to take third, missing out fourth, then block change to second, or change down to fourth and let the speed drop off, then take second. With my current car,a Ford Fiesta 1.4 petrol, there is considerable flexibility, and it will drop to just around 20mph in fith, which makes it easier to block change from fith to second.

My advice would be to play around and see what the car does, and at which speeds to block change. As Gareth said accelerate briskly in second, and then select fourth or fith as appropriate. Remember that the gear ratios will vary from car to car due to engine characteristics, power, where in the rev range the engine developes maximum power etc.

[Standard Dave]

Gear to go brakes to slow.

Using engine braking as it appears the OPs partner and father do is a rather old fashion technique used in large vehicles and old vehicles with ineffective brakes.

I use block changing down quite a bit at work travelling at high speed before braking hard and progressively selecting the correct gear to accelerate away from the hazard. All of our police vehicles are now diesel engines even the ARV and ANPR teams now have diesels.

I use block changing up when accelerating away from traffic lights and roundabouts after accelerating to clear other vehicles travelling up to the speed limit in say 2nd or 3rd gear I would then block change up to 5th or 6th gear.

[kfae8959]

Hello Helen, and welcome to the forum.

Sometimes I find "why?' is the most useful question! It certainly might help you understand the reasons your observer has for suggesting what he does, and the reasons your partner believes you shouldn't. At the moment it sounds as if you've got people insisting fairly firmly on different approaches, but they're not giving you information that might help you choose between them!

David

[daz6215]

Brakes to slow, Gears to go!

Advantages include:
Both hands are on the wheel for longer,
Less wear and tear on the car, remember, it's cheaper to change brake pads than a gear box and clutch,
Less wear on the driver, so therefore improving alertness,
Signalling of brake lamps to following drivers, earlier and more progressive braking providing more time to observe and plan ahead,
More fuel efficient,

It does take practice, try as Nigel says to get out of the frame of mind with regard to changing at certain speeds, you do what works for your vehicle, as soon as you feel transmission judder with a diesel, de-clutch! and then select the gear you need! Vision before Decision!

[waremark]

Given that your car is uncomfortable at low speed in a high gear, what your observer will be looking for will be for you to press the clutch down just before the speed at which the engine starts to struggle - it does not matter how fast you are still going when you press the clutch down. If you are braking at the time, the car is under good control, and there is no disadvantage of continuing to slow down with the clutch pressed down. You just don't bother about the gear until you have finished braking and are ready to start off again, when you go straight to the most suitable gear for the speed you are now at.

I am sorry your Observer will not deal with anything else until you have made this change to your driving, because as others have said there are other more important parts of advanced driving. However, it is true that an IAM Examiner will look for you to drive this way on an Advanced Test.

Perhaps it would help your marriage if your husband understands better what your Observer is trying to teach you. You might like to suggest that your Observer gives a demonstration drive with both you and your husband in the car.

[waremark]

Brakes to slow, Gears to go!

Advantages include:
Both hands are on the wheel for longer,
Less wear and tear on the car, remember, it's cheaper to change brake pads than a gear box and clutch,
Less wear on the driver, so therefore improving alertness,
Signalling of brake lamps to following drivers, earlier and more progressive braking providing more time to observe and plan ahead,
More fuel efficient,

A couple of points to add to this.

1. Rev-matching. When changing down, both for smoothness and for mechanical sympathy, you should have your right foot on the accelerator when you let the clutch out. This allows you to raise the revs to the correct engine speed to match the road speed in the new gear, and when you let the clutch out it will be smoother. You cannot do that if you change gear while you are still braking (unless you use a more advanced technique called Heel and Toe).

2. The brakes are the smoothest and safest way to slow, operating on all four wheels.

3. If you do one thing at once, you will probably do it better.

[Octy_Ross]

Perhaps it would help your marriage if your husband understands better what your Observer is trying to teach you. You might like to suggest that your Observer gives a demonstration drive with both you and your husband in the car.

I was going to suggest the same thing.

[jcochrane]

I would agree with the others in using the brakes to slow and not changing down through the gearbox when slowing.

I also drive a diesel and I expect your car will be similar to my own. With my car if you brake and the rpm drops below idle (1000rpm) the engine will react and try and push rpm back to idle. This will cause a lot of judder. So if in 4th gear when the rpm drops to about 1000rpm you will need to depress the clutch. The speed will be about 20 mph.

On block changing I would often do this both up and down the box. Like Gareth I would accelerate to about 3000/3500 rpm and then change up directly to the appropriate gear for that speed and so on until arriving at the cruising speed. So say from 2nd gear to 4th gear if cruising at 40mph

[IVORTHE DRIVER]

Hi Helen,

Further to the advice given in all the previous posts, also you need to bear in mind the road conditions if you are "block" changing.

In my minibus I can only skip 4th when going up the box if I am going downhill due to weight, speed etc, on level roads the engine would protest if I tried the same thing, going down the box is not a problem as the bus will go down to 30mph in 5th without hassle so then I can go for 3rd or even 2nd to pull away again, also I will often approach junctions in 4th or 5th, braking down to 20mph or less then skip to 2nd for the corner.

It does take practise to overcome your previous teaching and your partners attitude will not help!, get him out in the car with your instructor by all means but bear in mind he may never change his views, just dont let him bully you into not progressing, ultimately you will be the better driver.

Good luck

Ivor