Automatic gearbox driving?

[Bleedin Thumb]

You have got me worrying again:eek:

Can I check if my box has a gate to stop that happening to me? Or should I see what happens on my gear box?

You don't have to worry unless I'm on the same bit of road as yourself.

I dont know if you can do that with modern cars now. I was driving an old Holden with column shift.

Your probably the best person to find out for us though. After all its only a hire car!
You know what they say Live Fast, Die Young, Stay Pretty.

[DJ’s Timber]

You have got me worrying again:eek:

Can I check if my box has a gate to stop that happening to me? Or should I see what happens on my gear box?

If you can bypass the builtin safety gate:eek: , go for it . The autobox would probably come out the side of the car:eek:

[Stuart]

Most automatic shifters require you to hold in a button or a lever to be able to go into reverse, or into 1st (again, in an older car) so you can't bump the lever out of drive into anything but neutral. Get into the habit of going from neutral into drive and back to neutral without pushing the button, and you won't then surprise yourself one day selecting reverse or park (or 1st) by mistake as you are driving along at 100 clicks an hour.

[johnc]

Not all experiences have the same excitement factor as bleedin'thumbs. I clearly remember going to change the radio setting on a column shift auto and bumping the shift to R, gave me a hell of a shock when the car started to slow down in a hurry with thoughts of gearbox all over the road. A quick bump back to D and it was off and away, nobody startled, no drama. I remember someone's story of managing to accidently shift a manual into reverse at about 100kph, went in as smooth as silk, let out the clutch and then everything went pear shape with a bit of mechanical damage done. Pity no one was there to share the experience with him, but listening to the story held plenty of amusement.

I guess it doesn't matter what you drive you can stuff up anything, just keep your concentration and don't obsess about what is a pretty minor possibility. For most of us it will either never happen, or if it does is unlikely to cause much excitement.

John

[Iain]

Some of the new ones will allow the gear to be selected but nothing happens until the electronics says it's OK.

[Schtoo]

Define 'new'.

The Honda we have won't shift into lower cogs unless it's happy with the situation. Also won't shift into higher cogs until everything is warmed up. Does not have a button on the shifter, but is gated and you push down to get the 'dangerous' gears, has 4 forward cogs plus lockup converter in top.

And the car is now ten years old.

I guess it depends on what the car is supposed to be more than the age of it.

I'd think the Lancer Jow has isn't going to be sporting the latest and greatest slushbox, even of ten years ago. Prolly just a regular unit that changes gears and thats it.

Now, how about a Fordomatic? There's a technological marvel right there folks. About the size of a freaking house, and 2 forward cogs that work when they want to.

[Iain]

Honda 15 years
Toyota 10+ years
Holden/Ford How do they do that???
BMW way ahead of the rest of the field and couldn't give a toss
Mercedes almost up there with BMW (and Honda)
Jaguar Just another Ford really

[Doughboy]

I had an uncle that raced throughout NSW in an old EH and only ever had an automatic gearbox. He used to swear that he had it 'nicely' tweaked so that he could use it like a manual without the clutch. So does this make him the inventor of the clutchless manual?

Perhaps not since I can't remember if he was overly successful or not.

Pete

[Chris Parks]

There is a theory going around that the only reason that gearboxes have cases around them is to catch all the bits when things go slightly wrong.

[barnsey]

Driving auto's and manuals is a hazard particularly when you decide to change gear on an auto as if you were in a manual!!! Can be quite stoppy at times!!

Love the comfort of an auto and don't bother shifting to neutral - waste of time money and energy. Never ever put it in park unless you are in fact in that position and only when totally stationary.

Also do NOT fall for the trap of using the left foot for braking in an auto.
The number of cars I see with their brake lights on travelling up the motorway is scary - k after k.

Right foot only - Stop or go!!!

Jamie

[Landseka]

I still vividly remember my first drive in an automatic car, a 1963 EJ holden it was.

After I drove it around for 15 minutes or so getting more & more confident in it I approached a set of traffic lights which started to change , forcing me to stop from the fair clip that I was travelling at.:mad:

No time for thinking automatic box procedures, reflexes take over........

Right foot on the brake firmly......

Left foot on the clutch for a downshift......

Oh bugga, thats not a clutch, :eek: its a 8 inch wide brake pedal with now 2 size 10 feet pushing hard on it.

Result? Came to a screeching halt some 30 feet short of the intersection....how embarrassment

42 years ago & it seems like yesterday.

Regards

Neil

[Driver]

Also do NOT fall for the trap of using the left foot for braking in an auto.
The number of cars I see with their brake lights on travelling up the motorway is scary - k after k.

Right foot only - Stop or go!!!

I was a passenger in a car when the driver was doing this - driving with left foot resting on the brake pedal. After a while, I casually asked why he did it. He told me that his ankle got sore if he didn't have something to rest his foot on! :eek:

The same bloke used to indicate as he actually turned the wheel to take a corner.:confused:

[jow104]

Here is someone elses view from Europe.


The answer depends upon how mechanically sympathetic you are and on whose car it is!

In "Drive," if you release the brake, the car will gently move forward on level ground on tick-over. This means, obviously, that with the brake applied, you are "holding it back" - which, in turn, means that the transmission is then under tension, or "wind-up." It also means that the engine is under load, which may cause some modern engine-management systems to alter the fuel mixture slightly. Purists may say that this would lead to a loss in fuel economy, compared to an "in neutral" tickover, but I wouldn't like to have to survive on the difference.

The transmission will be robust enough to deal with this, but if it's unnecessary and you didn't do it, then there would be less strain, overall, on the transmission. This, theoretically, would tend to lead to less transmission problems, or longer transmission life, or both.

In my car (I drive a DSG 6-speed auto), I knock it into neutral on delays of more than, say, 20 seconds, simply because I don't like to think about the unnecessary strains and stresses (I'm mechanically sympathetic!). If it were a hire car, then sod it (I'm realistic, I'm not going to benefit, long-term).

It should also mean that the brake sevo should have a longer life?

[Schtoo]

I dunno about a DSG 6 speed auto, but the 4 speed (5?) in the Honda doesn't do any such thing.

If it's in neutral, the engine idles at about 1,000rpm. If in drive, it idles at about 800rpm. No change in throttle (engine throttle, not foot) position. In fact, most cars won't change what they are doing whether in neutral or drive, simply because that's not how the engine works, and if anything, the engine will use slightly less fuel since it's turning over slower.

Some cars may be able to add some more throttle, but they would use a 'fly by wire' throttle, and most cars with this technology don't have automatic gearboxes and fuel economy is not their primary concern.

As for the gearbox itself, it consists of a flexplate bolted to the engine flywheel. To this is bolted a torque converter, which is in essence a large hydraulic pump. In neutral or any gear, this pump is working to pump fluid around the gearbox for lubrication and cooling. As such, it is using up power.

(Hold it, that doesn't read right. But I am going to leave it until someone who is better versed in slushboxes corrects me. I only helped rebuild one of these monsters about 25 years ago so I don't know too much about them, other than from the pilot's seat.)

Possibly, the only benefit of being in neutral is that the gearbox is not under continuous strain when stopped. However, if you accelerate a little, then engage gear, you will shock the gearbox, occasionally quite badly, completely negating the 'advantage' of keeping it in neutral and possibly/probably causing damage rather than wear. This is very easy to do and I wouldn't recommend leaving it out of gear for a traffic light or train crossing. Stopped for longer might be sensible if you wish.

Brakes? No difference. Once they are stopped, they are stopped, no further wear will occur wether they are on or not, and they will be on anyway to keep the car from rolling.


But do be careful since the engine braking is reduced with an auto. That means downshifting when going down steep hills is a great idea since the engine can help take some of the braking duty, you won't use up so much worth of brakes (autos do use up more brakes, no question there) and you should, in a modern car with electronic fuel injection, gety a free ride down the hill since the engine will not burn any fuel when at speed but with no throttle applied. The injectors shut off until a set rpm point. In the Honda, that's about 1,500 rpm.

Also cools down the engine very quickly, and you can add braking by turning on the air conditioning while going down a large hill.


So there. (Thumbs nose at European know-it-all. )

[chrisp]

Leaving the auto trans in gear at stop lights causes far less wear to the internal clutches than shifting into neutral at lights.

I concur with rrich - leave it in Drive. Less changes = less wear.

Chris