Changing up a gear too soon?

tomreid10

Hi

Maybe one of the more technical on the forums can help me with this.

I have a Ford Focus Econetric diesel which does fantastic MPG.

One thing that bothers me though is that it's very difficult to get the gear changes right. There is a little green light that comes on on the dashboard when the car recommends that you should change up. But often I feel that this is too soon and the car sometimes vibrates a little when you push down on the accelerator.

My dad thinks it's bad for cars to accelerate when you have changed up too soon. i.e. if you hit third around 25 MPH.

Is this really the case?

Seems to get fantastic MPG (50MPG in town) when I adjust my driving style to change up earlier than I did before.

But am I harming the car?

cheers

LittleMissAspie

Yes it's bad to be in too high a gear, it "lugs" the engine and wears it out quicker. If the car lacks power just after you've changed up then it's too early.

atrixblue.-MFR-.

as my instructor used to say never let the engine struggle by changing up too soon or down too late it will cost him more money for extra wear.

regardless what the car tells you to do what you feel is right when its time to change up up and down.

vikingaero

Depends on the car and its gearing which varies from car to car. Also depends on the terrain. I suspect these change up lights were optimised with level ground. If there's a gradient the car will labour even more. If it's chugging a little then probably best to change gear a few hundred revs later albeit at the expense of economy.

daveyjp

My B class has one of those indicators - I ignore it, it's an indicator too far as it completely ignores the surroundings, the traffic levels, the terrain, your intentions etc etc. gears are for more than just achieving high mpgs.

3rd in 30 zones is often far more flexible than the 5th the car wants me to select.

Lum

The one in my Mondeo Econetic actually seems quite good, the gears you end up with are generally a case of dividing your speed by 10, e.g. 5th gear for 50mph. However it's worth noting that these lights aren't for your benefit.

When they do the official MPG testing, the gear change points are specified as part of the test and apply to all cars, unless the car has a shift light. So by fitting a shift light they can get much better official MPG figures without actually improving the car or engine in any way.

almillar

My sis' Mini has a similar system and she refuses to go above 3,000 rpm. Silly. It does sortof take into account engine load, how hard you want to accelerate and whether you're going up a hill or not, but just feels like you're making the engine strain too often. Driver still knows better IMO if you're not just gonna be cruising everywhere. Hope I don't get stuck behind you!
But hey, I'm not an automotive engineer!

Strider590

I've known a Focus 1.6 blow it's engine because the driver used to go around mini-islands in 4th gear.

MX5huggy

My Skoda one likes to tell me to change at 2000 approx normally this is alittle to early as it offers 6th at about 45 mph which then takes an age to get to 70.

It does work out when i am driving with gusto if I go to 5000 in 2nd then it does not offer 4 till past 3000 in 3rd.

Hammyman

tomreid10 wrote: »

Hi

Maybe one of the more technical on the forums can help me with this.

I have a Ford Focus Econetric diesel which does fantastic MPG.


Seems to get fantastic MPG (50MPG in town) when I adjust my driving style to change up earlier than I did before.

But am I harming the car?

cheers

Are you normally used to petrols? To get the best economy out of a diesel, you change up earlier than you would a petrol but not so low its rattling because of it.

Your dad is correct - for 1970.... :D

skiddlydiddly

You can feel it in the accelerator pedal if you're in the wrong gear as it will vibrate a little and generally the car will shudder too.