Manual versus automatic car?

John R

Tails142 wrote:

You can hear the engine straining when you're sitting in lights in Drive with the foot brake on, surely this is bad for the clutch disk and causes excess wear??

Except that auto transmissions do not have a clutch.


Unless someone can give a reasonable explanation why leaving the box in drive with the brakes on is bad I will remain unconvinced. Yes obviously there is more stress put on a number of components in drive but as the engine is at idle the level of force remains low, all of the components recieve many times the force levels in everyday acceleration and braking. Obviously wear on parts is cumulative so any extra wear has some effect. The same could be said for the gearbox internals wearing out quicker from all the extra gear changes going in and out of neutral at every traffic light.

R.O.R

Mercedes, on any of their recent auto's I've driven have a very good system for sitting in traffic. If you press the brake pedal all the way down to the floor it engages a "handbrake" to hold the car still until you accelerate away, allowing you to take your foot off the brake pedal.

Only discovered that while bored and sitting in traffic in an E320, but even the A150 I had as a hire car a few weeks back had it too - solves the breaklight issue and must be OK to hold the car like that in D if they've engineered it in to the car.

Tails142

Except that auto transmissions do not have a clutch.

Well surely there is some sort of a clutch like mechanism in an autobox that connects the gears to the wheels.

Opinion on this seems to me to be varied, with no argument really convincing me.

I drive a BMW 528i - when I brake I see the mpg needle go down as I brake, which to me would suggest that the engine is trying to work against the brakes.

When sitting at lights in drive, if I release pressure on the foot brake the car begins to creep forward even when they're still apllied - this to me would suggest that while in drive, the clutch disk (for want of a better word) is constantly engaged and while stopped at lights is still spinning against the pad that drives the axle which to me would constitute unncessary wear when I can just click it into neutral.

Perhaps some autobox's are designed differently but it seems to me less wear occurs if you take it out of drive and into neutral when stopped at lights for anything more than 30 seconds.

Wishbone Ash

R.O.R wrote:

Mercedes, on any of their recent auto's I've driven have a very good system for sitting in traffic. If you press the brake pedal all the way down to the floor it engages a "handbrake" to hold the car still until you accelerate away, allowing you to take your foot off the brake pedal

Mercedes buses also have a frequent halt button on the dash which can be pressed when stopped in traffic. It engages the brakes without the brakelights and releases them automatically when the accelerator pedal is pressed.

oscarBravo

Tails142 wrote:

Well surely there is some sort of a clutch like mechanism in an autobox that connects the gears to the wheels.

It's called a "torque converter". In simple terms, it's a pump that drives a turbine. There's no mechanical connection between the engine and the gearbox, so it can "slip" to its heart's content without wearing anything.

Tails142 wrote:

Perhaps some autobox's are designed differently but it seems to me less wear occurs if you take it out of drive and into neutral when stopped at lights for anything more than 30 seconds.

Changing gears involves mechanical wear. An idling torque converter doesn't.

whippet

I am no mechanic, actually far from it but I have to say that alot of the stuff posted here is rubbish !!!

- Automatic gearboxes do have clutches, some have two clutches (DSG type in VAG cars).
- As far as I know a Torque convertor will stop any strain on the engine while the car is stopped and in Drive with the foot brake engaged. The Torque convertor is what stops the engine from stalling everytime the wheels stop.

As for what to do at lights, I am sure that every owners manual I have read for an Auto car says to stop the car using the foot brake with the gear selector in Drive.

I am only recently full time driving a car with an Auto box and have driven plenty of others. Every car is different and every gearbox is different, reacts differently ... every driver drives differently.

For instance, I fell in love with the DSG auto box in the golf GTi and bought one, it is a pure auto when sitting in traffic, option of the triptronic with the almost instant gear change and even when parked on a fairly steep hill it will crawl up at idol. Also the DSG is more fuel efficient than the 6 speed manual.

As for the flip side, as part of a track day I drive a Porsche 911 with the triptronic gears and since I was used to the responsivness of the DGS change the porsche gear changes felt slow sluggish and generally terrible.

Auto boxes never really took off in europe and especially the UK and Ireland as traditionally they were much much heavier on juice and very sluggish, things are changing and with newer technology you will find an increasing amount of cars on our roads with Auto boxes.

the boss of me

worded wrote:

The obvious difference is the control on a car in bad weather.I hear.

As a kid I over heard the stick was better mechanically – is this still true.

Im thinking of an Octavia circa 2004 for city use - is it unwise to go automatic or would it be silly not to?

Never driven one.

Going back to the OP , I recommend the MK2 Octavia with a DSG box. I drive a 05 model with the 1.9 TDI and it's perfect for both the city and long distance driving.
There is no loss of control because you have tiptronic if you need it ( I rarely if ever use it). There is also the option of sports mode if you need to get away from the lights fast !!
There is also a form of traction control fitted , which you can disable if you want to( never felt the need myself).
As for being reliable, I have 150,000 km on mine and and the gearbox hasn't given an ounce of trouble. Neither has the rest of the car. You need to change gearbox oil every 60,000 km and to do that you have to bring it to a main dealer. It costs about €220.For normal use that's about every four years so not really worth worrying about.
Fuel consumption and acceleration are comparable to the manual version, little on no difference really.
All things considered I reckon auto is the way to go and you will never catch me in a stick shift again....

John R

whippet wrote:

I am no mechanic, actually far from it but I have to say that alot of the stuff posted here is rubbish !!!

You are correct, except that you are adding to the rubbish.

whippet wrote:

- Automatic gearboxes do have clutches, some have two clutches (DSG type in VAG cars).

Yes, the DSG box has two clutches but it is a completely different type of transmission than a regular auto. It is basically an advancement on a manual transmission that is automatically operated. A standard automatic uses a torque convertor to "slip" the drive from the engine and a planetary gearset rather than the friction clutch and cog box of a manual (or your DSG box).

jawlie

I remember when I got my first ever automatic car my garage mechanic asked why I wouldn't get a normal car and drive it properly.

Nowadays I have a stonkmobile, a 3.0l V6 Audi convertible with a tiptronic 6 speed gearbox. Why anyone would choose to use a clutch in traffic ( 1, 2. stop. 1, stop. 1,2,3 stop. etc etc between traffic lights etc) is a mystery, although I am sure the attitude still exists that automatic gearboxes in cars are, in some way, not for a proper driver.

tc20

Recent auto convert here too..

I've been driving for 20years, and nearly all in manuals, bar the odd hire car with auto box.
I can see the attraction for some of the 'involvement' of manually changing gears, especially when you're on the twisties, or having a back road blat. But to say that modern autos cannot compare is utter twaddle.

We have two cars, the recent addition being a 2.0l auto Accord, with Tiptronic. TBH i tried out the tiptronic for a bit of fun, but im more than happy to leave the car in D and go with the flow. For city driving, nothing beats an auto, i dont see why there is such a bias against them here. I have the Accord about 2months and love it. Apart from being slightly more thirsty than its manual equivalent, ive not a bad word to say for autos.

whippet

John R wrote:

You are correct, except that you are adding to the rubbish.

JohnR .. I think you should check that out again;

http://auto.howstuffworks.com/automatic-transmission4.htm

Anan1

Alun wrote:

It's not really a problem in daylight, but since the widespread introduction of high-level brake lights it has become a problem at night. I mean, if you're looking forward, you can't really help but stare into them, can you?

Well yes, actually. It's not like driving behind a car with foglights, where you have to look at them. You're at a standstill, you can look around.

Alun wrote:

Anyway, I'd dispute your suggestion that keeping your foot on the footbrake is going to make any significant difference to any whiplash injury you might suffer if rear-ended. Is this just supposition, or do you have anything to back it up?

The footbrake operates on all four wheels, whereas the handbrake only brakes the rear wheels. You can guess the rest.:)

ninty9er

Deleted User wrote:

Changing gears is hardly a chore now is it? I dont find it stressfull in the least. Barely notice myself going through the gears anymore. Holding a car on a hill with a manual isn't hard either! I will never buy one.

You obviously haven't been in South Tipp recently. For anyone bypasssing Clonmel on a daily basis, do yourself a favour and get an automatic. My hips, my arse and knee were killing me after all the f**king roundabouts from Limerick to Waterford, coupled with all the damn tractors and other SMVs.

An auto would have made my journey a whole lot nicer

galwaytt

whippet wrote:

I am no mechanic, actually far from it but I have to say that alot of the stuff posted here is rubbish !!!

...you said it.......on the other hand, I am.......

Automatic gearboxes do have clutches

,No, they don't.

some have two clutches (DSG type in VAG cars).

DSG is not an automatic. It's a dual-select manual with computer control and two clutch packs, to operate it automatically.There is a difference.

For instance, I fell in love with the DSG auto box in the golf GTi and bought one, it is a pure auto when sitting in traffic, option of the triptronic with the almost instant gear change and even when parked on a fairly steep hill it will crawl up at idol. Also the DSG is more fuel efficient than the 6 speed manual.

As for the flip side, as part of a track day I drive a Porsche 911 with the triptronic gears and since I was used to the responsivness of the DGS change the porsche gear changes felt slow sluggish and generally terrible.

.........damn, I was thinking of looking at a 968 Tiptronic....mmmm

Auto boxes never really took off in europe and especially the UK and Ireland as traditionally they were much much heavier on juice and very sluggish, things are changing and with newer technology you will find an increasing amount of cars on our roads with Auto boxes.

The other big reason is cost. +2k + extra VRT more or less kills it..........

ninty9er

whippet wrote:

automatic cars do have clutches

galwaytt wrote:

No, they don't.

Yes they do, just not the traditional friction pedal operated type

Wishbone Ash

Anan1 wrote:

The footbrake operates on all four wheels, whereas the handbrake only brakes the rear wheels

It could be argued that, although the park brake is applied to rear wheels only, it is unlikely to be released in a collision whereas the driver's foot may be moved involuntarily from the brake pedal by the initial force of the impact thereby releasing all four wheels.

SouperComputer

galwaytt im guessing you have never worked on an auto box?

To clear a few things up:

* Holding a car on a parking brake creates negligable brake wear on the friction surfaces as the car is stationary, its a clamping force thats in effect, holding the car in position rather than converting kinetic energy (movement) into heat. When stopped, effectively the brake calipers are bolted to the disks if you will.

* Autos are generally designed to be kept in D while at traffic lights. If you put it in N you can cause accelerated wear on the clutch packs, especially if you rev it! The torque converter and transmission are built to withstand the extra heat generated from being stopped at lights for a reasonably long period of time. At idle that is! Of course the constant shifting from N to D and back again also puts extra wear in the valve body AKA hydraulics.

* When you engage D and keep the car stationary, a drop in revs is completely normal. The engine is not being "strained" in any way. The torque converter is doing its job of applying the initial torque to get the car moving. The drop in revs is completely normal and within acceptable tolerances.


Back on topic, we have one manual car and one auto. I prefer to drive manual, even in traffic. Its not a case of better or worse, I just prefer to drive manual. They are harder to get over here though, even the E36 M3's are mostly auto.

/pukes

Anan1

Wishbone Ash wrote:

It could be argued that, although the park brake is applied to rear wheels only, it is unlikely to be released in a collision whereas the driver's foot may be moved involuntarily from the brake pedal by the initial force of the impact thereby releasing all four wheels.

This is, I suppose, possible in principle. I've only ever been rear-ended once, but I did see it coming. Anyone I know who's been rear-ended at lights has seen it coming too. Perhaps the trick at lights is not to gaze too intently into the brake lights of the car in front?;)

whippet

galwaytt wrote:

.........damn, I was thinking of looking at a 968 Tiptronic....mmmm

seriously, take one for a test drive .. but my initial reaction was that it was a pig of a gear box.

Of all the cars we drove that day the Porkie was the most dissappointing.

this is the track day we did http://www.palmersport.com

edited to change URL

BostonB

Anan1 wrote:

This is, I suppose, possible in principle. I've only ever been rear-ended once, but I did see it coming. Anyone I know who's been rear-ended at lights has seen it coming too. Perhaps the trick at lights is not to gaze too intently into the brake lights of the car in front?;)

Or use the handbrake?

Anan1

BostonB wrote:

Or use the handbrake?

If you'd taken the trouble to read before posting, you'd know why I use the footbrake.

BostonB

Anan1 wrote:

If you'd taken the trouble to read before posting, you'd know why I use the footbrake.

If you'd bothered to consider I had. Maybe you would have understood the point I was making. If you have the handbrake on you don't have to stare backwards at approaching traffic behind, or have your foot clamped on the brake pedal. You put the handbrake on, to rest your leg, and to stop yourself from being pushed forward if your foot comes off the pedal, or you get a shove from behind. Perhaps from someone behind, who's foot has slipped of the brake reaching for the last Malteser that rolled off the dash.

I was taught sitting on the foot pedal excessively was a bad habit. But over time whats bad and good driving behaviour seems to change. Like engine breaking etc.

Anan1

How come you haven't yet understood that the footbrake will lessen the amount by which the car is thrown forward if hit from behind, compared to the handbrake?

BostonB

Anan1 wrote:

How come you haven't yet understood that the footbrake will lessen the amount by which the car is thrown forward if hit from behind, compared to the handbrake?

Your failure in thinking is that best practise and safe driving works on the principle of worst case scenario not best case. Re: You can't keep your foot on the pedal, and thus no braking at all. You'll be shunted into the path of oncoming traffic. Not that everyone from 17 to 90 yrs of age, will be 100% alert, perfect reaction time, and keep the foot pedal full force, on the pedal time every time its needed. Even if thats once in 50yrs of driving.

ninty9er

BostonB, a little growing up is in order. I don't think Anan would recommend not using the handbrake at lights, just using the footbrake in addition as any decent instructor will teach!!

Anan1

BostonB wrote:

Your failure in thinking is that best practise and safe driving works on the principle of worst case scenario not best case. Re: You can't keep your foot on the pedal, and thus no braking at all. You'll be shunted into the path of oncoming traffic. Not that everyone from 17 to 90 yrs of age, will be 100% alert, perfect reaction time, and keep the foot pedal full force, on the pedal time every time its needed. Even if thats once in 50yrs of driving.

Nobody is asking you to use the footbrake - if you feel safer with just the handbrake than so be it.

BostonB

ninty9er wrote:

BostonB, a little growing up is in order. I don't think Anan would recommend not using the handbrake at lights, just using the
footbrake in addition as any decent instructor will teach!!

Whats with the jibe? Anan1 never clarified (till now) that he meant using it in addition to the handbrake. I've never heard the suggestion to use both before. However its oft remarked why you use the handbrake instead of a footbrake, for the reasons listed previously.

Anan1 wrote:

...I have already outlined why the footbrake is safer at traffic lights than the handbrake. ...

I would take "than" to mean use one or the other. If he meant both he should have made that clear.

Anan1 wrote:

... if you feel safer with just the handbrake than so be it.

I note that he has now clarified that he means both. Personally I think thats backtracking. But I'll give him the benefit of the doubt. I wonder if you asked a 100 people, how many would say they use the handbrake and the brake at the same time ever. Maybe 100 would say they do? :cool:

Anan1 wrote:

Nobody is asking you to use the footbrake ...

My bad I thought you did.

Anan1 wrote:

Your foot should be on the brake anyway.

Esel

Imo, keeping the brakes on while stopped in case you might be rear-ended is way over the top. (not talking particularly about automatics here). If you see the shunt coming, why not just apply maximum brake pressure at that point?

BostonB

I think the logic is. If you've good habits, you're less likely to forget to do something in a crisis. They'll be instinctual.

R.O.R

Personally, when coming to a stop in traffic or at traffic lights I will come to a halt using the foot brake and keep that depressed until the car behind has come safely to a stop - especially important at night on unlit roads.

If it looks like we'll be there for over a minute I'll engage the handbrake and release the footbrake - this saves the poor fecker behind staring into my high-level breaklight. If the guy behind is unlucky enough to be rear-ended then most of the energy would be dissapated by his car and the shunt he gives me wouldn't be enough to shift me forward with the handbrake on.

Above is how I was taught to drive a manual by my instructor and Dad. Auto's I'll generally leave in D with foot on the break unless you know you won't be moving for ages and I'll shift to P and put on handbrake (unless Merc as previously posted).