Thursday, Apr 03, 2008 at 18:13
I'm driving a 2644 actross Mercedes Benz Truck for work and It has the fuel economy computer showing on the dash and found that in traffic lower revs = better economy.
By short shifting (change up sooner) I used 3-4 L/ 100 less, still driving at full throttle, This is of course a modern, Euro spec heavy truck Diesel, but has changed the way I drive my Toyota.
I used to think that it would be better for the fuel economy to change down sooner and utilise more horsepower in the lower gear, but try and maintain the same throttle position, if you know what I mean, (my mate who has a 4.5l petrol swears by this theory).
I get the best fuel economy around 85ks when the roof rack is loaded, the harder you push the more it uses.
I general stick to the limit, cos the cruiser has 4.3:1 diffs and the revs start getting up there, as well as the wind resistance and can be felt especially on freeways where there is a long constant gradual
hill.
With my 96KW/285NM torque, it pretty much takes up most of the power, just to move the air, less air I have to push, the more power I get for the
hill, for instance, If hit a
hill at 110, It will start to die off and then settle as the speed washes off,
Point I'm making is that by increasing speed, I need more power, thus needing more fuel, regardless of what gear I'm in.
Shane
PS IMHO, If you have a "slippery" vehicle, lower revs will be better, If you drive something that isn't, IE tall, big
tyres, racks, I think speed (wind resistance) will be the overiding factor.
AnswerID:
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