Aprilia posted last year that the IAM advises selecting 3rd on an Autobox when in a 30 zone. I've been trying this, and owe Aprilia a virtual pint, as I would otherwise almost certainly have shot past a speed trap at more than this. I wondered why this is best practice.
1. To stop the 'box from searching? Or
2. To stop the 'box from changing into 4th, without the driver 'realising' and thus permitting his speed to creep up if he is paying more attention to the engine pitch than the speedo - as is likely in a town environment with lots to look out for?
The combination of these two factors means I now do this whenever I remember - most of the time. I am much more likely to be able to keep my speed down to 30 when in a 30 zone.
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I agree.
I drop my scooby into 3rd on the auto box frequently as it tends to 'freewheel' in Drive and the pickup is not as instantaneous as in 3rd. In 3rd, the drive always seems connected to the wheels, so one can get a better sense of speed and get better pickup.
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Espada III - well if you have a family and need a Lamborghini, what else do you drive?
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Ive been driving autos since 1987 and I always leave the selector in drive. Never had any freewheeling issues or hunting for gears.
Granted the last automatic I drove was of 1993 vintage so maybe technology has "progressed" to the point where automatics need to be shifted in order to be driven correctly. Maybe they should change the name to clutchless.
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Are we talking 5 speed boxes or 4 speed boxes. 30 mph in our C5 2.2 HDI is the very lower limit of 3rd gear and it is not really that happy at that speed.
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Would agree with using third gear in 30mph zones, I find the slightest down slope allows the speed to creep up,third gives more engine braking and prevents this and also you do not have to keep dabbing the brakes.
ndbw
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Won't do a lot for fuel economy though.
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Use it up : Wear it out : Make do : Do without
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>Won't do a lot for fuel economy though.
Won't make any difference.
My car (4-speed) will change up at about 31 when under virtually no load. As soon as you load it again, down it changes. If you don't load it, the speed creeps up - as my mind thinks it is still in 3rd and adjusts the revs accordingly.
So, this leads to wear on the 'box. Which changes up again when load is removed.
So far as fuel consumption is concerned, sticking in 3rd saves fuel as you don't change gear. Furthermore, it shouldn't ever be in top in a 30 zone, as that's speeding.
Agreed?
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I think I have another one of my invisible posts!
My point was that our C5 is really labouring in 3rd gear at 30 mph. If the car was left in auto then, as in Mapmaker's case, it will change down to 2nd gear, if there is any load put on it. The car has to be travelling at 35 mph, at least, for it to stay happily in 3rd gear. With a 5 speed box, 3rd gear would no doubt be a practical selection for speeds just below 30 mph.
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Machika,
I saw your post! As with a manual (where the lower gear advice is equally relevant) it depends on the engine/box combination. In my manual Xantia HDi 110 second is ideal in a thirty, the older BX really needs third and a keener ear.
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My Astra auto has a 'sport' button which keeps the box in gear longer for some 'enthusiastic' driving.
I rarely use it, BUT find that it is an ideal for these situations, where it is easier to engae the button (top of gearshift) than to actually change down.
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Some people want a Sonata! On the V6 at least, the four speed box drops to 3rd at 35mph indicated whatever you do, even with the "manual" mode selected. (I do not know any reason, the manual Magentis with virtually the same engine could happily come down to 20 in fifth.)
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Machika, I saw your post! As with a manual (where the lower gear advice is equally relevant) it depends on the engine/box combination. In my manual Xantia HDi 110 second is ideal in a thirty, the older BX really needs third and a keener ear.
I am surprised, as I would have thought it would be fine in 3rd gear, with having a 5 speed box. Our 90 bhp Xantia TD is fine in 3rd at 30 mph (right down to 20 mph actually). It is also ok in 4th at 30 mph (unless going up a gradient). Low down torque should be one of the strengths of a diesel engine.
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I am surprised, as I would have thought it would be fine in 3rd gear, with having a 5 speed box. Our 90 bhp Xantia TD is fine in 3rd at 30 mph (right down to 20 mph actually). It is also ok in 4th at 30 mph (unless going up a gradient). Low down torque should be one of the strengths of a diesel engine.
Sorry, we're in danger of mixing issues. Xantia HDi pulls OK at 30 in third, albeit at the lower end of rev range. Won't hack it in fourth though - revs well under 1500.
Use of second in 30 zone gives a marked change in engine note from 25 to 30, ears as well as eyes do their bit to keep under the limit. I think the OP's point was that you could acheive the same effect with an autobox by selecting 3 to lock out higher gears.
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It's a long time since I drove auto (or even a petrol), so since getting the Omega, I've taken easily todropping it down a gear.
Seems to work well, too, but it does make you double check, when stopping at lights, that you've not just moved the lever back to drive, rather than neutral.
& Mrs V, since doing her Police style, Ride Drive day, is also running the Mx5 in 3rd, around town.
VB
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