Definition of Automatic Transmission

[Roger Mills]

Since this seems to be a contentious issue - as witnessed by one recent
thread - I decided to try to find out what definition the DVLA uses for
driving licence purposes. Since I couldn't find a definition on their
website, I emailed them - and this is what they said in reply:

"A vehicle with automatic transmission means a class of vehicle in which
either-

(a) the driver is not provided with any means whereby he may vary the gear
ratio between the engine and the road wheels independently of the
accelerator and the brakes, or
(b) he is provided with such means but they do not include a clutch pedal or
lever which he may operate manually."

The wording doesn't seem to me to be as watertight as it might be, but I
think it means essentially that anything with a manually (foot or hand)
operated clutch is a manual and anything without is an automatic even if the
driver has to tell it (or has the option of telling it) when to change gear.
I take "clutch pedal or lever" to means "clutch pedal or clutch lever" as
opposed to "clutch pedal or (any other sort of) lever".

Definition (a) leaves open the possibility of having a manual clutch as a
starting device but not allowing the driver to take any part in gear
selection thereafter but - as far as I am aware - there ain't any cars like
that, anyway. [There may, of course, be cars with automatic (e.g.
centrifugal) friction clutches - which would still be automatics under
definition (b) since there is no pedal or lever to control them.]

To me - as an ex-engineer(!) - all the discussion about whether the design
includes a torque converter and planetary gears, etc. is irrelevant - what
matters is the *functionality* regardless of the technology used to achieve
it.

[David Taylor]

Post by Roger Mills
Since this seems to be a contentious issue - as witnessed by one recent
thread - I decided to try to find out what definition the DVLA uses for
driving licence purposes. Since I couldn't find a definition on their
"A vehicle with automatic transmission means a class of vehicle in which
either-
(a) the driver is not provided with any means whereby he may vary the gear
ratio between the engine and the road wheels independently of the
accelerator and the brakes, or
(b) he is provided with such means but they do not include a clutch pedal or
lever which he may operate manually."
The wording doesn't seem to me to be as watertight as it might be, but I
think it means essentially that anything with a manually (foot or hand)
operated clutch is a manual and anything without is an automatic even if the
driver has to tell it (or has the option of telling it) when to change gear.
I take "clutch pedal or lever" to means "clutch pedal or clutch lever" as
opposed to "clutch pedal or (any other sort of) lever".

But the DVLA have a very good reason for specifying it as "any car
without a manually opeated clutch": they don't want to let someone
who sits a test in a car without a clutch drive a car with a clutch.

[Gordon Hudson]

Post by David Taylor
But the DVLA have a very good reason for specifying it as "any car
without a manually opeated clutch": they don't want to let someone
who sits a test in a car without a clutch drive a car with a clutch.

That is a very precise and accurate explantion of the issue.

I have never driven a Smart but I don't think they have a clutch pedal so
they are classed as automatics.
There are lots more cars that have semi automatic type gearboxes and no
clutch although you have to change gear manually.

[Roger Mills]

In an earlier contribution to this discussion,

Post by David Taylor

Post by Roger Mills
Since this seems to be a contentious issue - as witnessed by one
recent thread - I decided to try to find out what definition the
DVLA uses for driving licence purposes. Since I couldn't find a
definition on their website, I emailed them
etc.

But the DVLA have a very good reason for specifying it as "any car
without a manually opeated clutch": they don't want to let someone
who sits a test in a car without a clutch drive a car with a clutch.

Agreed. But presumably, someone who takes a test in a "fully" automatic -
where you just stuff it in 'D' and let it get on with it - would then be
able to drive a "semi"- automatic - which has no clutch but still requires
the driver to select the gears manually?

I assume that you are saying in effect that the DVLA's definition of
automatic may be wider than other definitions in order to include
*everything* which doesn't have a manual clutch - such that it incorporates
both fully-automatics and semi-automatics? That sounds entirely reasonable.

But I hope that you agree that whatever definition you use needs to be based
on what it *does* - as experienced from the driver's seat - not on the nitty
gritty of *how* it does it.

[David Taylor]

Post by Roger Mills
In an earlier contribution to this discussion,

Post by David Taylor

Post by Roger Mills
Since this seems to be a contentious issue - as witnessed by one
recent thread - I decided to try to find out what definition the
DVLA uses for driving licence purposes. Since I couldn't find a
definition on their website, I emailed them
etc.

But the DVLA have a very good reason for specifying it as "any car
without a manually opeated clutch": they don't want to let someone
who sits a test in a car without a clutch drive a car with a clutch.

Agreed. But presumably, someone who takes a test in a "fully" automatic -
where you just stuff it in 'D' and let it get on with it - would then be
able to drive a "semi"- automatic - which has no clutch but still requires
the driver to select the gears manually?

I believe so. As far as I'm aware, most (but probably not all)
semi-automatics are capable of behaving as fully automatics. Or indeed,
refuse to allow you to select a "wrong" gear.

Post by Roger Mills
I assume that you are saying in effect that the DVLA's definition of
automatic may be wider than other definitions in order to include
*everything* which doesn't have a manual clutch - such that it incorporates
both fully-automatics and semi-automatics? That sounds entirely reasonable.

Yes.

Post by Roger Mills
But I hope that you agree that whatever definition you use needs to be based
on what it *does* - as experienced from the driver's seat - not on the nitty
gritty of *how* it does it.

Yes, I agree, the technology used doesn't really affect whether it's
automatic or not. If the car is capable of selecting the correct
gear without assistance from the driver it is an automatic.

The difference between semi-auto and manual is a bit more artificial,
but still quite simple if you just base it on whether a clutch needs
to be used.

[Tommy]

Post by David Taylor
Yes.

Post by Roger Mills
But I hope that you agree that whatever definition you use needs to
be based on what it *does* - as experienced from the driver's seat -
not on the nitty gritty of *how* it does it.

Yes, I agree, the technology used doesn't really affect whether it's
automatic or not. If the car is capable of selecting the correct
gear without assistance from the driver it is an automatic.
The difference between semi-auto and manual is a bit more artificial,
but still quite simple if you just base it on whether a clutch needs
to be used.

personally I can see no upside of an automated clutch system apart from the
fact that CO2 emmssions are lower than a proper auto - which effects your
"car tax"

The big downside (i.e impossible) I understand is trying to park in a spot
where the ground is not level

[Silk]

Post by Tommy
personally I can see no upside of an automated clutch system apart from the
fact that CO2 emmssions are lower than a proper auto - which effects your
"car tax"

I can't think of any area where the DSG is not superior to a
conventional auto.

Post by Tommy
The big downside (i.e impossible) I understand is trying to park in a spot
where the ground is not level

I don't understand that. On the DSG you can just release the foot-brake
and the ECU will allow the car to creep without having to touch the
accelerator and a light touch on the brake will disengage the drive - a
bit like slipping a clutch. You effectively just control the speed with
the brake pedal. As long as the hill is not excessively steep the ECU
will compensate. Parking is often given as one of the areas where
automatics struggle but, just like everything else, you can do it with
practice.

[Douglas Hall]

Parking is often given as one of the areas where automatics struggle but,
just like everything else, you can do it with practice.

I'd actually say I find my auto easier when parking, than a manual.

[Dave Plowman (News)]

Post by Douglas Hall

Parking is often given as one of the areas where automatics struggle
but, just like everything else, you can do it with practice.

I'd actually say I find my auto easier when parking, than a manual.

SMG transmissions are a pain as there is no creep. The clutch is fully
disengaged at rest to prevent wear which of course isn't the case with a
torque convertor.

[Chris Bartram]

Post by Douglas Hall

Parking is often given as one of the areas where automatics struggle but,
just like everything else, you can do it with practice.

I'd actually say I find my auto easier when parking, than a manual.

Well, I'd agree, for a conventional, torque-converter auto. Having never
driven a semi auto, a DSG, or SMG variant (i.e: I've driven manual and
conventional, TC + Epicyclic autos) I can't comment, but i'd imagine
that depending on how well the clutch control is implemented would have
a great effect on how hard it would be to park, and how long the
clutch(es) will last.

I'll probably buy a DSG one day though, when a car equipped with it
meets my needs and budget- unless anyone wants to give me an A3 TDI DSG?

[Silk]

Post by David Taylor
Yes, I agree, the technology used doesn't really affect whether it's
automatic or not. If the car is capable of selecting the correct
gear without assistance from the driver it is an automatic.

Indeed. I'm still surprised that some have tried to argue otherwise.

Post by David Taylor
The difference between semi-auto and manual is a bit more artificial,
but still quite simple if you just base it on whether a clutch needs
to be used.

I would tend to use the term semi-automatic in the context of
transmissions to describe a box that has manual selection of gears but
the physical movement of cogs and clutches is performed by
electro-mechanical servos. I've only ever seen them on buses. I can't
think of any current mainstream cars that use them.

[Roger Mills]

In an earlier contribution to this discussion,

Post by Silk
I would tend to use the term semi-automatic in the context of
transmissions to describe a box that has manual selection of gears but
the physical movement of cogs and clutches is performed by
electro-mechanical servos. I've only ever seen them on buses. I can't
think of any current mainstream cars that use them.

I once (7 or 8 years ago) had a test drive in a Merc A-Class which had some
sort of transmission which I would describe as semi-automatic.

As far as I can remember, it had some sort of automatic clutch - probably
centrifugal - to get you going but you changed gear with a fairly
conventional looking gear lever which had a sensor which detected movement
and operated a servo to disengage the clutch.

Assuming I have described it correctly (it was a long time ago!), I presume
that it would have been an "automatic" for driving licence purposes.

[Derek Geldard]

Post by Silk

Post by David Taylor
Yes, I agree, the technology used doesn't really affect whether it's
automatic or not. If the car is capable of selecting the correct
gear without assistance from the driver it is an automatic.

Indeed. I'm still surprised that some have tried to argue otherwise.

Post by David Taylor
The difference between semi-auto and manual is a bit more artificial,
but still quite simple if you just base it on whether a clutch needs
to be used.

I would tend to use the term semi-automatic in the context of
transmissions to describe a box that has manual selection of gears but
the physical movement of cogs and clutches is performed by
electro-mechanical servos. I've only ever seen them on buses.

That was a preselector gearbox. The selection being made by putting a
stubby gearstick into the appropriate slot in the gate at any time.
The cogs were moved electrically initiated the next time the driver
disengaged the clutch (with his foot) and re -engaged it.

Post by Silk
I can't think of any current mainstream cars that use them.

There have been some recent American ones that use the system below.

I recall a friends Ca 1961 Austin Westminster that had "manumatic"
transmission. IIRC it had both an electric clutch operated by a button
on the column change lever, and a centifugal one. Gears had still to
be selected in the traditional column change manner.

ICBW. ;-)

DG

[Dave Plowman (News)]

Post by Derek Geldard

Post by Silk
I would tend to use the term semi-automatic in the context of
transmissions to describe a box that has manual selection of gears but
the physical movement of cogs and clutches is performed by
electro-mechanical servos. I've only ever seen them on buses.

That was a preselector gearbox. The selection being made by putting a
stubby gearstick into the appropriate slot in the gate at any time.
The cogs were moved electrically initiated the next time the driver
disengaged the clutch (with his foot) and re -engaged it.

A genuine pre-select box didn't involve any electrics or electronics. Or
gear swopping either in the true sense. Pushing the 'clutch' pedal
operated brake bands on the ring of epicyclic gear trains which remained
in constant mesh. The London Routemasters had an electric selector
mechanism, but I'm not sure about the actual workings of the box itself.

[Roger Mills]

In an earlier contribution to this discussion,

Post by Dave Plowman (News)
A genuine pre-select box didn't involve any electrics or electronics.
Or gear swopping either in the true sense. Pushing the 'clutch' pedal
operated brake bands on the ring of epicyclic gear trains which
remained in constant mesh. The London Routemasters had an electric
selector mechanism, but I'm not sure about the actual workings of the
box itself.

There is some information about the pre-selector gearbox patented by Wilson
at http://en.wikipedia.org/wiki/Wilson_gearbox

This was used in pre-war and early post-war Daimler and Lanchester cars
among others, and a bigger version manufactured by Self-Changing Gears was
used in a lot of buses. These usually had a fluid coupling (similar to a
torque converter but providing no torque multiplication) as a starting
device, and the left pedal (which wasn't actually a clutch) was pressed to
cause a gearchange to occur.

[Many of the buses on which I travelled to school in the 1950's had this
type of transmission].

[Derek Geldard]

On Sun, 17 Jun 2007 21:12:39 +0100, "Roger Mills"

Post by Roger Mills
There is some information about the pre-selector gearbox patented by Wilson
at http://en.wikipedia.org/wiki/Wilson_gearbox
This was used in pre-war and early post-war Daimler and Lanchester cars
among others, and a bigger version manufactured by Self-Changing Gears was
used in a lot of buses. These usually had a fluid coupling (similar to a
torque converter but providing no torque multiplication) as a starting
device, and the left pedal (which wasn't actually a clutch) was pressed to
cause a gearchange to occur.

Thanks for that. It begins to make some sense now. My posting was
based on eager chit chat between schoolboys in the early '60s none of
whose parents had cars but several were bus drivers.

That setup would more/less equate to the manumatic setup with a
centrifugal clutch for setting-off, and an electric clutch to change
cogs.

Clearly with a "Fluid Flywheel" for setting-off and an epicyclic
gearbox it would be only necessary to select the right set of brake
bands at the right time. This would be easily accomplished with the
small mimic "gear lever" used to set the next gear change in advance
and a "manual" foot control to initiate the change at the right time.

Post by Roger Mills
[Many of the buses on which I travelled to school in the 1950's had this
type of transmission].

*Luxury*.

We went school on Leyland PD2's, with straight cut gears which
*Ground* their way up the t' 'ills.

DG

[Dave Plowman (News)]

Post by Derek Geldard
Clearly with a "Fluid Flywheel" for setting-off and an epicyclic
gearbox it would be only necessary to select the right set of brake
bands at the right time. This would be easily accomplished with the
small mimic "gear lever" used to set the next gear change in advance
and a "manual" foot control to initiate the change at the right time.

The small selector on a Routemaster wouldn't provide enough leverage to
set the brake band valves and would have had a very tortuous linkage. It
was an electrical selector controlling servos. A traditional pre-selector
had a chunky lever similar to a column change except that it moved in a
straight line. I once owned a BSA car with a pre-selector box. ;-)

[unknown]

Roger Mills <***@googlemail.com> wrote:

[Pre-selector box with fluid flywheel]

Post by Roger Mills
[Many of the buses on which I travelled to school in the 1950's had this
type of transmission].

So did my dad's car, an Armstrong Siddeley Star Saphire. I always like
hte fact that the column shift had a position marked "Emergency" put it
to that and poke the shift pedal and it would accelerate like a scalded
cat.

[Dave Plowman (News)]

Post by unknown
So did my dad's car, an Armstrong Siddeley Star Saphire. I always like
hte fact that the column shift had a position marked "Emergency" put it
to that and poke the shift pedal and it would accelerate like a scalded
cat.

Memory certainly plays tricks. ;-)

[unknown]

Post by Dave Plowman (News)

Post by unknown
So did my dad's car, an Armstrong Siddeley Star Saphire. I always like
hte fact that the column shift had a position marked "Emergency" put it
to that and poke the shift pedal and it would accelerate like a scalded
cat.

Memory certainly plays tricks. ;-)

Hell for the time it was fast, a saloon car that could hit 100mph.
Remember that at that time most people were driving cars that caouldn't
even make 70mph, if given a week to do so.

[Dave Plowman (News)]

Post by unknown

Post by Dave Plowman (News)

Post by unknown
So did my dad's car, an Armstrong Siddeley Star Saphire. I always
like hte fact that the column shift had a position marked
"Emergency" put it to that and poke the shift pedal and it would
accelerate like a scalded cat.

Memory certainly plays tricks. ;-)

Hell for the time it was fast, a saloon car that could hit 100mph.
Remember that at that time most people were driving cars that caouldn't
even make 70mph, if given a week to do so.

I do remember them quite well as a pal of my father had one. But I don't
remember it taking off like a scalded cat - they were pretty heavy. I do
remember being very impressed with the low speed acceleration of a
contemporary Series II Ford Zephyr, though.

[Elder]

Post by Silk
I've only ever seen them on buses. I can't
think of any current mainstream cars that use them.

Sensonic and Selespeed I think are two car semi auto systems.
I think on old original Beetle 1500 had the option of a semi-auto,
clutchless manual shift too.

[TripleS]

Post by Silk

Post by David Taylor
Yes, I agree, the technology used doesn't really affect whether it's
automatic or not. If the car is capable of selecting the correct
gear without assistance from the driver it is an automatic.

Indeed. I'm still surprised that some have tried to argue otherwise.

Post by David Taylor
The difference between semi-auto and manual is a bit more artificial,
but still quite simple if you just base it on whether a clutch needs
to be used.

I would tend to use the term semi-automatic in the context of
transmissions to describe a box that has manual selection of gears but
the physical movement of cogs and clutches is performed by
electro-mechanical servos. I've only ever seen them on buses. I can't
think of any current mainstream cars that use them.

Just as a matter of interest, where does the Wilson pre-selector system
rank in all this? This is a system that was used on many Daimler and
Lanchester cars of the 1950s.

It by no means amounted to automatic transmission, but it wasn't a
manual transmission in the normal sense.

Does anybody else remember these?

Best wishes all,
Dave.

[Adrian]

Post by TripleS
Just as a matter of interest, where does the Wilson pre-selector system
rank in all this? This is a system that was used on many Daimler and
Lanchester cars of the 1950s.
It by no means amounted to automatic transmission, but it wasn't a
manual transmission in the normal sense.
Does anybody else remember these?

Remember 'em? I seem to recall *mentioning* 'em earlier in this thread...

The DSG is very similar in that it preselects the next gear (in the
"other" gearbox), only changing when it deems it necessary (vs the
preselector's "when you hit the change pedal")

[TripleS]

Post by Adrian

Post by TripleS
Just as a matter of interest, where does the Wilson pre-selector system
rank in all this? This is a system that was used on many Daimler and
Lanchester cars of the 1950s.
It by no means amounted to automatic transmission, but it wasn't a
manual transmission in the normal sense.
Does anybody else remember these?

Remember 'em? I seem to recall *mentioning* 'em earlier in this thread...
The DSG is very similar in that it preselects the next gear (in the
"other" gearbox), only changing when it deems it necessary (vs the
preselector's "when you hit the change pedal")

I don't know anything about the DSG transmission, but if it is a system
that requires the driver to operate a gear change pedal to engaged a
previously selected gear, that doesn't amount to automatic functioning -
but maybe that's not what you're saying.

The Wilson pre-selector system was fitted to a 1953 Lanchester (an
offshoot of Daimler at that time) that we had in the family. That had a
steering column selector quadrant marked: 4 3 2 1 N R and instead
of a clutch pedal it had a gear change pedal. The procedure with that
car was to select the gear you wanted, but nothing happened until you
pressed and released the gear change pedal, at which point the gear was
engaged. This was not automatic transmission by any stretch of the
imagination. I suppose the nearest you could get to it would be to
select and engage 4th gear while at rest, and make a leisurely start,
letting the fluid flywheel take care of things.

Best wishes all,
Dave.

[Dr Zoidberg]

Post by TripleS

Post by Adrian

Post by TripleS
Just as a matter of interest, where does the Wilson pre-selector
system rank in all this? This is a system that was used on many
Daimler and Lanchester cars of the 1950s.
It by no means amounted to automatic transmission, but it wasn't a
manual transmission in the normal sense.
Does anybody else remember these?

Remember 'em? I seem to recall *mentioning* 'em earlier in this
thread... The DSG is very similar in that it preselects the next gear (in
the
"other" gearbox), only changing when it deems it necessary (vs the
preselector's "when you hit the change pedal")

I don't know anything about the DSG transmission, but if it is a
system that requires the driver to operate a gear change pedal to
engaged a previously selected gear, that doesn't amount to automatic
functioning - but maybe that's not what you're saying.

The DSG has two modes
In fully automatic mode it will change gear for you at a suitable point
based on speed and what you are doing with the accellerator or brake. There
is no clutch and you don't need to touch the gear level from setting off up
to motorway speeds and beyond. As far as the user experience is concerned
this is identical to a "normal" automatic.
In semi automatic mode you can tap the gear lever forwards or back (and use
steering wheel mounted paddles on some cars) to change gears as you see fit.
The electronics do retain some control and if you hit the redline it will
change up for you anyway and won't let you go from 6th to 1st without
slowing down to a sutable speed first.


--
Alex

"I laugh in the face of danger. Then I hide until it goes away"

www.drzoidberg.co.uk www.ebayfaq.co.uk

[TripleS]

Post by Dr Zoidberg

Post by TripleS

Post by Adrian

Post by TripleS
Just as a matter of interest, where does the Wilson pre-selector
system rank in all this? This is a system that was used on many
Daimler and Lanchester cars of the 1950s.
It by no means amounted to automatic transmission, but it wasn't a
manual transmission in the normal sense.
Does anybody else remember these?

Remember 'em? I seem to recall *mentioning* 'em earlier in this
thread... The DSG is very similar in that it preselects the next gear (in
the
"other" gearbox), only changing when it deems it necessary (vs the
preselector's "when you hit the change pedal")

I don't know anything about the DSG transmission, but if it is a
system that requires the driver to operate a gear change pedal to
engaged a previously selected gear, that doesn't amount to automatic
functioning - but maybe that's not what you're saying.

The DSG has two modes
In fully automatic mode it will change gear for you at a suitable point
based on speed and what you are doing with the accellerator or brake. There
is no clutch and you don't need to touch the gear level from setting off up
to motorway speeds and beyond. As far as the user experience is concerned
this is identical to a "normal" automatic.
In semi automatic mode you can tap the gear lever forwards or back (and use
steering wheel mounted paddles on some cars) to change gears as you see fit.
The electronics do retain some control and if you hit the redline it will
change up for you anyway and won't let you go from 6th to 1st without
slowing down to a sutable speed first.

It sounds as if it can handle all progress between zero mph and maximum
speed without the driver doing any gear changes, in which case that
sounds like fully automatic to me, and the fact that a driver can choose
to override gear selections doesn't detract from that, surely.

Best wishes all,
Dave.

[Dr Zoidberg]

Post by TripleS

Post by Dr Zoidberg

Post by TripleS

Post by Adrian

Post by TripleS
Just as a matter of interest, where does the Wilson pre-selector
system rank in all this? This is a system that was used on many
Daimler and Lanchester cars of the 1950s.
It by no means amounted to automatic transmission, but it wasn't a
manual transmission in the normal sense.
Does anybody else remember these?

Remember 'em? I seem to recall *mentioning* 'em earlier in this
thread... The DSG is very similar in that it preselects the next
gear (in the
"other" gearbox), only changing when it deems it necessary (vs the
preselector's "when you hit the change pedal")

I don't know anything about the DSG transmission, but if it is a
system that requires the driver to operate a gear change pedal to
engaged a previously selected gear, that doesn't amount to automatic
functioning - but maybe that's not what you're saying.

The DSG has two modes
In fully automatic mode it will change gear for you at a suitable
point based on speed and what you are doing with the accellerator or
brake. There is no clutch and you don't need to touch the gear level
from setting off up to motorway speeds and beyond. As far as the
user experience is concerned this is identical to a "normal"
automatic. In semi automatic mode you can tap the gear lever forwards or
back
(and use steering wheel mounted paddles on some cars) to change
gears as you see fit. The electronics do retain some control and if
you hit the redline it will change up for you anyway and won't let
you go from 6th to 1st without slowing down to a sutable speed first.

It sounds as if it can handle all progress between zero mph and
maximum speed without the driver doing any gear changes, in which
case that sounds like fully automatic to me, and the fact that a
driver can choose to override gear selections doesn't detract from
that, surely.

Yep , that's how most people would see it.

[Adrian]

Post by Dr Zoidberg

Post by TripleS
It sounds as if it can handle all progress between zero mph and
maximum speed without the driver doing any gear changes, in which
case that sounds like fully automatic to me, and the fact that a
driver can choose to override gear selections doesn't detract from
that, surely.

Yep , that's how most people would see it.

"Most people" would refer to the contents of the transmission, whatever
flavour it may be, as "cogs"...

[Silk]

Post by Adrian
"Most people" would refer to the contents of the transmission, whatever
flavour it may be, as "cogs"...

You must know some strange "most people".

[Silk]

Post by Dr Zoidberg
Yep , that's how most people would see it.

Those of us who are not worthy, certainly. ;-)

[Dave Plowman (News)]

Post by TripleS
It sounds as if it can handle all progress between zero mph and maximum
speed without the driver doing any gear changes, in which case that
sounds like fully automatic to me, and the fact that a driver can choose
to override gear selections doesn't detract from that, surely.

The Steptronic slush box on my BMW gives near enough the same choices. But
with smooth gearchanges at all times. ;-)

[Silk]

Post by Dave Plowman (News)
The Steptronic slush box on my BMW gives near enough the same choices. But
with smooth gearchanges at all times. ;-)

Yesterday's technology.

[Douglas Hall]

Post by Silk

Post by Dave Plowman (News)
The Steptronic slush box on my BMW gives near enough the same choices. But
with smooth gearchanges at all times. ;-)

Yesterday's technology.

Personally, I'd rather trust a good, conventional auto at the moment.

Report back when your DSG has over 200k miles on the clock, 'cos as well as
everything else (performance, responsiveness, smoothness) I want something
that will last as long as I keep the car, not let me down, not cause me to
have to spend time and money fixing it or servicing it.

Now I'm not accusing DSG boxes of being unreliable, or all these things -
but I'd want some established proven servicability history, before opting
for one.

[Dave Plowman (News)]

Post by Douglas Hall

Post by Silk

Post by Dave Plowman (News)
The Steptronic slush box on my BMW gives near enough the same
choices. But with smooth gearchanges at all times. ;-)

Yesterday's technology.

I've not yet got the original of this so will comment here.

The advantage of a DSG box was said to be less power loss. But modern
multi-speed epicyclic transmissions lock out the TC after every change -
in other words it is just used for starting off and cushioning the
changes. They are certainly not yesterday's technology. Gears which still
'slide' could be considered to be though.

Post by Douglas Hall
Personally, I'd rather trust a good, conventional auto at the moment.
Report back when your DSG has over 200k miles on the clock, 'cos as well
as everything else (performance, responsiveness, smoothness) I want
something that will last as long as I keep the car, not let me down,
not cause me to have to spend time and money fixing it or servicing it.
Now I'm not accusing DSG boxes of being unreliable, or all these things
- but I'd want some established proven servicability history, before
opting for one.

And you need to ask the cost of a clutch change. It's frightening.

[Douglas Hall]

Post by Dave Plowman (News)

Post by Douglas Hall

Post by Silk

Post by Dave Plowman (News)
The Steptronic slush box on my BMW gives near enough the same
choices. But with smooth gearchanges at all times. ;-)

Yesterday's technology.

I've not yet got the original of this so will comment here.
The advantage of a DSG box was said to be less power loss.

Yup - and spookily fast upshifts, and in fairness, pretty quick downshifts.
Not that I've driven one, but I do wonder how smooth they do all of that,
when not pressing on.

Post by Dave Plowman (News)
But modern
multi-speed epicyclic transmissions lock out the TC after every change -
in other words it is just used for starting off and cushioning the
changes.

Mine does it in every gear 'cept 1st. For some of the lower gears, it does
wait for coolant to get to a certain temp.

Post by Dave Plowman (News)
They are certainly not yesterday's technology. Gears which still
'slide' could be considered to be though.

Post by Douglas Hall
Personally, I'd rather trust a good, conventional auto at the moment.
Report back when your DSG has over 200k miles on the clock, 'cos as well
as everything else (performance, responsiveness, smoothness) I want
something that will last as long as I keep the car, not let me down,
not cause me to have to spend time and money fixing it or servicing it.
Now I'm not accusing DSG boxes of being unreliable, or all these things
- but I'd want some established proven servicability history, before
opting for one.

And you need to ask the cost of a clutch change. It's frightening.

It's that I had in mind, really. But I'm wondering if it could create an new
era of being an uneconomic repair after a certain amount of depreciation has
occurred.

[Manual Man]

Post by David Taylor
But the DVLA have a very good reason for specifying it as "any car
without a manually opeated clutch": they don't want to let someone
who sits a test in a car without a clutch drive a car with a clutch.
--
David Taylor

Out of interest, how many people each year book/pass an automatic
test? Anyone on here have any experience of it actually being any
easier to pass? (How many people have ever failed a manual test on
gear changes alone? - even with with a juddery Vauxhall clutch) Do the
DSA supply the pass rate statistics? Seems totally daft unless someone
doesn't have 2 legs! ADIs want a couple of quid more per hour usually,
you'll never be able to hire lots of things/drive company pool
vehicles/have the pick of the entire model ranges etc etc.

[Adrian]

Anyone on here have any experience of it actually being any easier to
pass?

I know a few people who have auto-only licences.

Seems totally daft unless someone doesn't have 2 legs!

Or just lack basic clutch control.

[Dave Plowman (News)]

Post by Manual Man
Out of interest, how many people each year book/pass an automatic
test? Anyone on here have any experience of it actually being any
easier to pass? (How many people have ever failed a manual test on
gear changes alone? - even with with a juddery Vauxhall clutch) Do the
DSA supply the pass rate statistics? Seems totally daft unless someone
doesn't have 2 legs!

Given the number of times you see a learner stall a manual I can imagine
many wanting to learn on an auto.

[Dave Plowman (News)]

Post by Roger Mills
Since this seems to be a contentious issue - as witnessed by one recent
thread - I decided to try to find out what definition the DVLA uses for
driving licence purposes. Since I couldn't find a definition on their
"A vehicle with automatic transmission means a class of vehicle in which
either-
(a) the driver is not provided with any means whereby he may vary the
gear ratio between the engine and the road wheels independently of the
accelerator and the brakes, or (b) he is provided with such means but
they do not include a clutch pedal or lever which he may operate
manually."
The wording doesn't seem to me to be as watertight as it might be, but I
think it means essentially that anything with a manually (foot or hand)
operated clutch is a manual and anything without is an automatic even
if the driver has to tell it (or has the option of telling it) when to
change gear. I take "clutch pedal or lever" to means "clutch pedal or
clutch lever" as opposed to "clutch pedal or (any other sort of) lever".
Definition (a) leaves open the possibility of having a manual clutch as
a starting device but not allowing the driver to take any part in gear
selection thereafter but - as far as I am aware - there ain't any cars
like that, anyway. [There may, of course, be cars with automatic (e.g.
centrifugal) friction clutches - which would still be automatics under
definition (b) since there is no pedal or lever to control them.]
To me - as an ex-engineer(!) - all the discussion about whether the
design includes a torque converter and planetary gears, etc. is
irrelevant - what matters is the *functionality* regardless of the
technology used to achieve it.

I've been told the BMW SMG transmission is classed as a manual for licence
terms even although it has no clutch pedal and a fully auto mode. Seems to
me 'they' only read the 'manual' part in the name and went by that as it's
an auto by any true meaning of the word.

I'd define an auto as a transmission which allows the car to attain from
rest any speed it is capable of with no more input from the driver than
selecting 'drive' and pushing the accelerator.

The above SMG transmission won't allow the vehicle to stall or exceed the
maximum safe engine speed regardless of the selector position so little
different in practice to a slush pump BMW steptronic as regards driving
the thing.

[Silk]

Post by Dave Plowman (News)

Post by Roger Mills
Since this seems to be a contentious issue - as witnessed by one recent
thread - I decided to try to find out what definition the DVLA uses for
driving licence purposes. Since I couldn't find a definition on their
"A vehicle with automatic transmission means a class of vehicle in which
either-
(a) the driver is not provided with any means whereby he may vary the
gear ratio between the engine and the road wheels independently of the
accelerator and the brakes, or (b) he is provided with such means but
they do not include a clutch pedal or lever which he may operate
manually."
The wording doesn't seem to me to be as watertight as it might be, but I
think it means essentially that anything with a manually (foot or hand)
operated clutch is a manual and anything without is an automatic even
if the driver has to tell it (or has the option of telling it) when to
change gear. I take "clutch pedal or lever" to means "clutch pedal or
clutch lever" as opposed to "clutch pedal or (any other sort of) lever".
Definition (a) leaves open the possibility of having a manual clutch as
a starting device but not allowing the driver to take any part in gear
selection thereafter but - as far as I am aware - there ain't any cars
like that, anyway. [There may, of course, be cars with automatic (e.g.
centrifugal) friction clutches - which would still be automatics under
definition (b) since there is no pedal or lever to control them.]
To me - as an ex-engineer(!) - all the discussion about whether the
design includes a torque converter and planetary gears, etc. is
irrelevant - what matters is the *functionality* regardless of the
technology used to achieve it.

I've been told the BMW SMG transmission is classed as a manual for licence
terms even although it has no clutch pedal and a fully auto mode. Seems to
me 'they' only read the 'manual' part in the name and went by that as it's
an auto by any true meaning of the word.

I think someone may have been pulling your plonker. I notice the
"Automotive Engineers" are suspicious by their absence on this thread. :-)

Post by Dave Plowman (News)
I'd define an auto as a transmission which allows the car to attain from
rest any speed it is capable of with no more input from the driver than
selecting 'drive' and pushing the accelerator.
The above SMG transmission won't allow the vehicle to stall or exceed the
maximum safe engine speed regardless of the selector position so little
different in practice to a slush pump BMW steptronic as regards driving
the thing.

DSG is exactly the same in this respect - it can't be stalled or over
revved in normal driving.

[Roger Mills]

In an earlier contribution to this discussion,

Post by Dave Plowman (News)
I've been told the BMW SMG transmission is classed as a manual for
licence terms even although it has no clutch pedal and a fully auto
mode. Seems to me 'they' only read the 'manual' part in the name and
went by that as it's an auto by any true meaning of the word.

Does that mean that if you pass your test in one of those, you're then
allowed to drive a *proper* manual car?

[Dave Plowman (News)]

Post by Roger Mills

Post by Dave Plowman (News)
I've been told the BMW SMG transmission is classed as a manual for
licence terms even although it has no clutch pedal and a fully auto
mode. Seems to me 'they' only read the 'manual' part in the name and
went by that as it's an auto by any true meaning of the word.

Does that mean that if you pass your test in one of those, you're then
allowed to drive a *proper* manual car?

I'd guess so, but you'd have to be a *very* rich learner to afford the
insurance on any BMW that offers this transmission, which is only the very
high performance models. It's basically crap, using a single clutch. So
extremely rough changing. BMW have at long last realised this and will be
fitting twin clutch types in a year or so.

[Chris Bartram]

Post by Dave Plowman (News)
It's basically crap

Really? That's quite a surprise. After all, BMWs are usually well
engineered, whatever else you might think about them.

[Justin Cole]

Post by Chris Bartram

Post by Dave Plowman (News)
It's basically crap

Really? That's quite a surprise. After all, BMWs are usually well
engineered, whatever else you might think about them.

The M5 seems to cope quite well...

Justin.

[Dave Plowman (News)]

Post by Justin Cole

Post by Chris Bartram

Post by Dave Plowman (News)
It's basically crap

Really? That's quite a surprise. After all, BMWs are usually well
engineered, whatever else you might think about them.

The M5 seems to cope quite well...

Oh, when pressing on playing boy racer thumpy gearchanges don't matter -
you'd do the same with a manual. But when trickling along in heavy traffic
they become a real PITA. Of course some don't notice. Which says a lot for
their normal gear changing skills.