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Low speed, High gear watch

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    is it bad for the gears to be driving in fourth gear or even fifth gear at speeds of around 20mph?
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    If the engine is labouring it can use more fuel but it shouldn't really be much of a problem.
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    If the engine's struggling it's less economical (and pretty noisy :p:)
    It depends on the car though, for example my boss' car is fine in 5th gear at 30mph, but mine would struggle and needs to be going at at least 40pmh :dontknow:
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    yes but will it be doing ANY damage to the gears whatsoever
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    may i throw this in....

    so why do taxi drivers do it?
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    (Original post by alexsheppard11)
    may i throw this in....

    so why do taxi drivers do it?
    Economy. When you drive as many miles as they do, you'd want to scrimp and save on as much fuel use as possible.

    Higher gears produce lower engine revs, therefore less fuel consumption for a given speed. As previous posters have mentioned, however, this shouldn't be taken to the extreme of labouring the engine as you will waste fuel which attempting to accelerate unsuccessfully as well as causing engine damage which would cost over time.
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    Not if you drive a V8. :cool:
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    its generally more economical to drive in high gears at low speeds
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    (Original post by butthead7)
    its generally more economical to drive in high gears at low speeds
    Erm, not if the engine's struggling it's not.
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    (Original post by xmarilynx)
    Erm, not if the engine's struggling it's not.
    Depends on how much torque the engine makes I can drive my car in 5th gear at 35mph. It won't do any harm to the engine but if your car has no torque whatsoever say a honda or a mazda then you will get bad gas mileage and the engine will have to work harder.
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    i thought it wasn't the revs that determine how much gas is used but how much pressure is placed on the gas pedal?
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    (Original post by Pheonixx)
    i thought it wasn't the revs that determine how much gas is used but how much pressure is placed on the gas pedal?
    At lower revvs you will have to apply more pressure to keep the same speed.
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    (Original post by Texan88)
    At lower revvs you will have to apply more pressure to keep the same speed.
    exactly, some of the posts seem to state the opposite in this thread, confusing!. So we should all drive around with nice high revs.
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    If the engine is labouring more throttle will be required to maintain a particular speed. With the throttle open more the engine management unit with make the mixture richer and hence use more fuel despite the lower revs. You should try and keep the engine in the power band. On modern cars the EMU determines the amount of fuel injected into the cylinder so in certain situations the amount of revs doesn't matter. For instance if you change down gear to keep your speed under control while going down hill the emu injects only the minimum amount of fuel into the cylinder and the energy of the car descending is used to keep the engine from stalling.
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    Is that even possible? I was doing 25 in 4th gear once and my foot was to the floor on the accelerator but it wasn't doing anything so...!
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    Generally the principle is the higher the gear the more fuel saved. Though driving in high gears at low speed strains the gearbox and will cause it to stop working. That can be an expensive job, and in some cases it's not even worth salvaging it; some people just buy a cheap car.
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    A lot of it also depends on your driving style. You have to remember that down low in the rev band (especially for petrol cars and more performance orientated diesels) that you have to relax because you've lost a lot of your potential acceleration. If you're doing 35mph in 4th (lowest I can realistically go in my car as far as revs go) then it'll pull all the way up to 50 (my engine doesn't rev much) without using much fuel if I give it the time to do so. If I put my foot down then it will guzzle a lot trying to accelerate faster than it's capable of though.
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    (Original post by lilangel890)
    Is that even possible? I was doing 25 in 4th gear once and my foot was to the floor on the accelerator but it wasn't doing anything so...!
    What car ?
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    Taxi drivers never use 5th gear xD

    I was in a 1.9TDi Galaxy last night, the computer was showing an average of 27.9mpg that's piss poor for a VAG 1.9TDi! I know it's a bigger car but mines never been less than 43mpg :/

    It did say service due, have the engine light and airbag lights on and was on 177,000miles even though it was 07 reg.

    Suppose the MAF had gone or something...

    Bummer.
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    There's no problem with this, I drive my dads 2.0 litre diesel around at 25mph in 6th gear haha. Im not entirely sure why because we get free fuel so fuel efficiency isn't exactly a worry but hey ho
 
 
 
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