Results 1 to 10 of 10

Thread: Changing Gear - when to do it?

  1. #1
    Join Date
    Mar 2014
    Posts
    6

    Default Changing Gear - when to do it?

    I ran a search in the forum, as well as looking at the first page manually and couldn't find anything, so being new to the forum I'm sorry if this topic is already under discussion elsewhere.

    When it comes to changing gear there are a number of opinions and we all know that it does depend on the car, the conditions, the driver's ability etc. That said there are generally considered to be some basic rules you can follow and I wondered what other people think they are? Let's assume, for the sake of discussion that you're driving on flat, good quality roads.

    When I was learning to drive in the early 2000s I was told by my instructor that 1st gear is basically for manoeuvring (with clutch control) and very slow speeds of 0 - 10 mph. 2nd gear was then for speeds of 10 - 20 (most often used on the busy and cramped residential roads around where I lived), 3rd for 20 - 30, 4th for 30 - 40 and 5th for 40+. Obviously this was approximate and you still had to listen to the car. When it comes to shifting down gears, you should slow the car to the appropriate speed and then select the appropriate gear.

    My Dad, on the other hand, has a very different view and believes that you should go up the gears quickly and get into 5th as soon as you can, often doing so between 20 and 30 mph. This gives a better fuel economy and allows you to basically sit back and relax, only shifting down a gear if you really have to - usually because you've been forced to slow down to the point where the car is really complaining about the higher gear. He still uses 1st gear for manoeuvres of course but he always applies power when doing so; I don't think I've ever seen him use clutch control.

    The third point of view I've come across is that of an older gentleman I worked with once who felt that you should be shifting gears constantly, moving up each in turn as you go faster and moving down each in turn as you go more slowly. He said it was safer. He also tended to use power when manoeuvring - a lot of it and heavy use of the break!

    Obviously people from different generations were taught differently but my thoughts at the moment are that 'my way' is the modern way of safe driving and that 'my Dad's way' is the way of economical driving (which would very much appeal to him ). In other words it's driving the best way you can vs driving the best way for your car/bank balance. When it comes to the older gentleman I mentioned, I think that the difference has more to do with the change in technology over the years - we just don't need to shift so much any more. I'd like to hear other people's views though.

  2. #2
    Join Date
    Apr 2012
    Posts
    2,895

    Default

    Driving in the highest gear possible has always been a way of achieving the best fuel consumption, albeit to the detriment of the engine and transmission. When I attended a course on driving a heavy lorry economically, I was told to keep the revs within a fairly narrow band, which did entail a fair amount of gear changing (bearing in mind that there were sixteen to choose from).

    A good driver uses his 'feel' for the car. They will know when to change gear because it 'feels' right. If you are accelerating hard, possibly on a slip road to a motorway, you will 'wind' the revs up more in each gear. If you are pulling away from traffic lights, in a 30mph limit, with a fair expectation that you will soon be stopped again, you will change up as soon as the car allows.

    It is very difficult to describe in words how to make these decisions. The only way to learn, is to do it with a good instructor, who will tell you when it is correct.

  3. #3
    Join Date
    Apr 2007
    Posts
    8,529

    Default

    Broadly speaking, I would agree with Santa. To be more definitive, from my own perspective, there are a few situations which apply as common sense.
    1. If the car does not respond immediately to a slight increase on the accelerator, the gear is too high and the engine labouring unnecessarily.
    2. I always select a lower gear for descents, aiming for the engine to act as a brake rather than continually using the brakes themselves - being a diesel, the high compression ratio is ideal for this.
    3. I always set off in first gear from stationary - the longer the clutch is slipping, the more rapid is the wear on the friction discs. The exception to this would be when facing down hill, in which case 2nd gear would be selected, and the clutch engaged as the car begins to roll forward.
    4. Moving up through the gears is quicker, and at a lower speeds, on down gradients than upward gradients.
    5. Up hill, the gear will not be high enough to make the car labour. Down hill - see comment #3.
    6. When crawling in slow-moving traffic, a low enough gear is selected to allow the car to move forward with the clutch fully engaged. Fortunately, my first gear allows a crawl considerably less than walking speed.
    These are basic gear selection techniques but there are others dependent on variable circumstances - difficult, as Santa says, to describe in detail.

  4. #4
    Join Date
    Apr 2012
    Posts
    2,895

    Default

    Another point worth mentioning is 'block' changing. With most cars having 5, or even 6, gears these days, block changing, or skipping gears, is normal practice and is a good driving skill to acquire.

    In essence you do not always need to use all the gears in sequence when changing up or down. For example (with a 5 speed box), If you are facing downhill, you may start off in 2nd, change to 4th and then 5th. When decelerating off a motorway you may change down to 4th on the slip road, and then to 2nd as you approach the roundabout at the end. There are many other scenarios.

    When it comes to block changing you can choose any gear you like, as long as it will be suitable for the circumstances.

    3rd to 5th is a very common block change, especially after an overtake. In fact it will likely have been 5th to 3rd to overtake and then 3rd to 5th to cruise again once completing the overtake. Incidentally it might not be an overtake, just increased acceleration to any suitable speeds for 5th.

    On a driving test, you would be expected to block change whenever circumstances allow.

  5. #5
    Join Date
    Oct 2009
    Posts
    706

    Default

    Drive as many seem to do now. You put your foot down hard and screw the engine to the point of explosion before changing up. Ignore all speed limits as they are there only to annoy you and impede your travel in a dangerous manner. Life would not be fun without a few thrills and car wrecking can be just as exciting as golf or fishing. Another method is to use the car as an extension of you, driving carefully and with sympathy for the cars mechanics and road conditions. There is no point going into too high a gear too soon as you will achieve nothing and make the car unresponsive. Your approximations are about right but my car does not like 5th under 50 mph. You will find this kind of driving more relaxing and economical. (smiley big grin) {usually shown as a smiley but this website continues to fire on 2 cylinders out of 8 since it's last service in a back street garage approved by the RAC}

  6. #6
    Join Date
    Apr 2007
    Posts
    8,529

    Default

    Agree, Santa. My car is 6-speed and my most common change is from 4th straight to 6th gear. The difference in ratio between the two gears is so small that, on near-flat or slight downward gradient, fifth gear is quite unnecessary.

  7. #7
    Join Date
    Mar 2014
    Posts
    6

    Default

    Some interesting replies, thank you. With particular regards to my point about changing technology having an effect on when we change gear, is that something any of you have experienced over the years? I haven't personally but then I only have the last decade to go on, experience wise. I take the point that block changing is much more common now; any other changes you've noticed?

    @Trainman: Please be mindful of your blood pressure.

  8. #8
    Join Date
    Sep 2007
    Location
    Scotland
    Posts
    8,689

    Default

    I've been jumping gears for years, for example, going down hill, and using the cars momentum going uphill, then change into the gear required when I get to the top.It's the same as, using all the road, if nobody else is using that bit of the road, then I use it. Some drivers think that is dangerous, but hey! Driving is a dangerous thing, there's nothing wrong with what I do, if it's safe to do so.

  9. #9
    Join Date
    Apr 2007
    Posts
    8,529

    Default

    Quote Originally Posted by justsomeguy View Post
    Some interesting replies, thank you. With particular regards to my point about changing technology having an effect on when we change gear, is that something any of you have experienced over the years? I haven't personally but then I only have the last decade to go on, experience wise. I take the point that block changing is much more common now; any other changes you've noticed?

    @Trainman: Please be mindful of your blood pressure.
    Having been driving for over 60 years now, I find that general handling of cars has changed significantly over that time. My early cars had smaller diameter pistons and a long stroke, so available power wasn't produced as happened when the "over square" arrangement came into being. Power-to-C.C. ratios went through the roof, compared to my first Standard 9 (rated at 9 horse power with a capacity of about 1,100 c.c.). Gear changes were more frequent then for the smallest of increases in up ward gradient. Added to that, the modern diesel engine is very tolerant of being made to climb up in speed from a higher-tan-normal gear (although I don't do that). And mpg has also increased by a considerable amount since those days.
    Gear changing is only one aspect of the improvements over the years - today's 'Joe Public' car is more comfortable and easier to drive than many of the luxury up-market models of yesteryear.
    I think the saddest thing about modern drivers is that, if they drove according to the rules and prevailing conditions, and maintained their cars properly, the modern motorcar could be one of the safest forms of transport.

  10. #10
    Join Date
    Oct 2009
    Posts
    706

    Default

    Quote Originally Posted by justsomeguy View Post
    Some interesting replies, thank you. With particular regards to my point about changing technology having an effect on when we change gear, is that something any of you have experienced over the years? I haven't personally but then I only have the last decade to go on, experience wise. I take the point that block changing is much more common now; any other changes you've noticed?

    @Trainman: Please be mindful of your blood pressure.
    No trouble with BP just oil pressure and cylinder heads !

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •