Fuel Saving Advice - The Use Of Gears

A few months ago, I took some time out to go out on the road for an hour with an IAM Roadsmart, Masters level driver

For those unfamiliar, the IAM Roadsmart group runs two levels of advanced driving test. The standard advanced driving test that most members have passed, and the masters version, which assess skills over a longer period of time on the road, requires a constantly commentary, takes a more exacting look at habits and needs to be repeated every few years in order to remain valid

Something that immediately caught my eye was the use of the gears and engine rev range

The driver basically changed gear outside his house and didn’t change out of that gear for a very, very long time with speeds reaching 40mph at times without the car being placed into 3^rd

I asked about this and the responsive engine braking is the reason it’s done, allowing a driver more control over the speed with the gas pedal alone, minimising the use of the brakes and of course leading to less wear and tear on the braking system

But what about fuel consumption?

The driver pointed at his trip computer, which showed that he was currently doing 99.9mpg, as most cars do under engine braking, he went on to explain that his car achieved around 45mpg when driven like this, as it spends more time in the engine braking zone than people who need to use the brakes more

Reasonable logic, but completely against the advice of the DVSA, who advocate early changes and considerate block changes as a way of maximising fuel consumption

It's also against advice from the Energy Saving Trust, who advise short shifting and no block changing for fuel efficiency. Their course demonstrates these gains using trip computers

ALL three organisations are in agreement that drivers that look ahead and plan their driving will reduce fuel consumption by eliminating unnecessary acceleration and gear changes

So, over the following weeks I did some experimenting with my own car, in particular with regards to using more rev range and holding back on changing up the gears

What I’ve found is that you don’t use as much fuel as you expect when you drive like that, but I did use more. My car achieved around 50mpg, which is about what it does on an average day’s work with learner drivers at the wheel and 14% below the 57mpg that I expect when I'm driving it

Having said that, from watching the trip computer, I do believe that the driver was right when he said that the car spends more time utilising engine braking but it also seems that just holding a steady speed also gives decent fuel economy, regardless of what gear you’re in

In 4^th gear for example, on the motorway, my car is achieving around 55mpg, which is really close to the 57mpg I'd expect if it was in 6^th with cruise control being used at 70mph (best speed for fuel consumption is always around 50mph). Now I’d estimate that it’s revving a good 1,500 revs higher in 4^th and my expectation was to see fuel consumption drop a lot, lot more than it did

I tried putting them all together on a recent trip to Wales, looking and planning  as far ahead as possible, letting the engine sing when I felt I’d benefit from the extra control provided by the high revs, short changing in free flowing, but heavy traffic where we're just trundling along and then block changing when getting up to the speed limits and cruising… the trip yielded it’s usual 57mph, no different to when I use either of those methods on their own terms

So my advice is to plan your driving, it's the most important side of it. Utilise your gears based on what you can see ahead and how you think your driving plan looks. Plan to hold a steady speed, use engine braking as much as you can and try to eliminate unnecessary gear changes. Don't overly worry about revs, and definitely don't change gear so early that the engine labours - that definitely wasn't good for fuel consumption!

The group, Staffordshire Advanced Riders and Drivers meets at around 715pm on a Thursday evening at Sandyford’s community fire station and they offer a free driving assessment to anyone interested in exploring the world of advanced driving. No appointment is required but you can get more information by contacting their facebook page

Nick Heath Driver Training helps people of all levels and abilities with their driving. Established in 2005 and based on the South Cheshire / North Staffordshire border in the UK, I can help you to obtain a licence, become a driving instructor, regain your driving confidence or reduce your road risk for work purposes. I am a regular contributor to local and national radio when driving items come up in the news and am willing to contribute to the wider driver training conversation

Anyone wanting more information should call 0800 8 20 2038