Automatic gearbox thread!

mike65

This for auto-heads and those who might be yet!

I've had my auto for 10 days now and after a few days to get used to its "adaptive" behaviour I'm beginning to use it to best effect and am getting nearly 32 mpg over the last 140 miles odd.

There's a few things I'm curious about, one is do all auto boxes rev higher when in neutral? Mine goes from 850 to 1000. Do all boxes require pressing the brake pedal before engaging a gear does anyone find they have look to move from say D to R?

Also whats with 1-2-3 gears, can these be selected 'manually' while keeping the power on?

Does your auto "hold" a gear longer when accelerating with cold fluid?

Mike.

_Kaiser_

mike65 wrote:

This for auto-heads and those who might be yet!

I've had my auto for 10 days now and after a few days to get used to its "adaptive" behaviour I'm beginning to use it to best effect and am getting nearly 32 mpg over the last 140 miles odd.

There's a few things I'm curious about, one is do all auto boxes rev higher when in neutral? Mine goes from 850 to 1000. Do all boxes require pressing the brake pedal before engaging a gear does anyone find they have look to move from say D to R?

Also whats with 1-2-3 gears, can these be selected 'manually' while keeping the power on?

Does your auto "hold" a gear longer when accelerating with cold fluid?

Mike.

Firstly.. I love my Auto Mitsubishi Mirage (Big Nelly will probably be on later to say it requires starting it with a rubber band and it's slow etc but howandever )

Can't give you a figure on what the revs are in Neutral (no rev counter) but it does seem to rumble a bit more than manual equivalents. You have to push the brake in to take it out of Park and hold the button in on the selector to move into/through Reverse alright. It won't move through it unless the button is pressed at the time - prevents you acidentially knocking it into Reverse while going for Neutral.

I'm not sure about downshifting from Drive to 1/2/3 - never tried it to be honest as Drive works for me, and I'd be a bit afraid of a rather violent jerky stop or whatever, but you can definitely shift up without problems while keeping the power on.

Don't know about the cold start. Mine is definitely nippy enough off the line and through the gears anyway in the mornings.
Incidentially a full tank in mine is about €35 at the moment and gets me through a week of daily commuting to and from Navan with room to spare.

Hope that's of some use, and welcome to the club

Guy:Incognito

Mine revs in around the 800-900 iirc. On my box I have P-R-N-D-3 and L I think (must check that)
I've never been told exactly how to drive an auto so just made it up. The way I do it is start in P(wont start in any other gear), put my foot on the brake, drop the handbrake, move to D and come off the brake.


Whats the deal with sitting at lights? Are you supposed to leave it in D with your foot on the brake or put it in Neutral?

As for what revs it changes at. Mine depends on how hard you accelerate. If you plant the accelerator it'll change at around 4500-5000, or in sports mode it changes just before the redline (65000 iirc). If your in say 3rd and you plant it, it drops to 2nd then works up. If you tap it in a certain way you can pretty much change gear when you like.

_Kaiser_

Stekelly wrote:

Mine revs in around the 800-900 irrc. On my box I have P-R-N-D-3 and L I think (must check that)
I've never been told exactly how to drive an auto so just made it up. The way I do it is start in P(wont start in any other gear), put my foot on the brake, drop the handbrake, move to D and come off the brake.


Whats the deal with sitting at lights? Are you supposed to leave it in D with your foot on the brake or put it in Neutral?

I do both depending on how long I think I'll be there. Just make sure to have your foot on the brake before you take it out of Neutral tho

Oh and that's how I start mine up as well so I guess we're doing something right. Like you I was never really told any formal procedure.

Guy:Incognito

Yeah, it's kind of a common sense thing I suppose.

_Kaiser_

Well come to think of it generally I reflexively put it in Neutral (with my foot on the brake or the handbrake on) so as to prevent it creeping forward in Drive if I lift off (side note: that does come in handy on hills though).

One question though. Do yours beep when you put them in Reverse. Mine sounds like a truck backing up

dubtom

Mine usually ticks over at about 850, I have noticed a slight increase when selecting N from D, but I think it's normal, when I say slight probably about 50.
Mine has a low, 2,3 and drive. I've used them once or twice with no ill effects, just to see what happens. You may find while driving in D that a slight let up of the pedal will engage the next gear, rather than waiting for it to reach a rev limit. I mean by that that it's not nessary to say speed up untill you reach 60 or 2000 revs to get it into fifth, you can tiddle a long at 30 by using the let up thingy, although you probably knew that already.I find mine takes a nano second in the morning to engage at start up, figure it's just the oil taking it's time circulating.If in doubt about yours a change wouldn't do no harm, my mechanic insists because it's red or green or whatever it's ok, I dont agree, I was told to change it every 5000 miles by the guy I bought it from ( mines a taxi) and it would stand to me, I've had no problems so far (crosses legs, fingers and eyes just to be safe)
PS, I would never go back to manual.

Whats the deal with sitting at lights? Are you supposed to leave it in D with your foot on the brake or put it in Neutral?

just read that, always always put it in N when stopped, leaving it in gear is like a manual in first half clutched, it will eventually do damage.

mike65

I am going to have the fluid and filter changed as I have no record of a recent change. On the D or N at idle, the Royal Society of the Prevention of Accidents (yes such a thing exists!) says leave car in D, neutral actually causes more wear.

Mike.

colm_mcm

Here's how it works (bear in mind I'm more used to Jap stuff)

P: Park mode, this locks up the transmission and is used when the car is parked, it usually allows the car to roll under 12" backwards or forwards, so handbrake should also be used when the car is stopped. Engaging "P" is usually made more difficult (usually by a button, and/or a brake pedal switch) to prevent accidental application

R: Reverse: Reverse mode, this one is pretty obvious. again accidental selection is prevented by a button, and/or a brake pedal switch

N: Neutral: Neutral is usually used when the car is temporarilly stopped, eg. at traffic lights, it prevents the car from creeping (crawling forward when the car is in Drive) If you are in very slow moving traffic going downhill, Neutral can be used. There usually isn't any safety device preventing shifting between "N" and "D"

Drive: This allows the gearbox to select any of the forward gears

3: 3 Position: This allows the gearbox to select any of the gears up to and including third gear, and locks out 4th gear and overdrive, handy if you're planning some overtaking and saves you the amount of time it takes the box to change down from top gear.

2: 2 Position: This allows the gearbox to select any of the gears up to and including second gear, This can be useful if you're doing a lot of low speed urban driving eg. mini roundabouts everywhere! and don't want the car to keep changing between 2nd and 3rd.

L: Lockout: This locks the gearbox in first gear, this is handy if you're doing low speed manouvering, or are on a very sharp incline and need to keep your speed very low without cooking the brakes

O/D: Overdrive Switch: This changes the top gear ratio, handy if you're doing high speed overtaking, the slight increase in engine revs make acceleration better. These switches are being phased out, and are usually fitted to 4 speed automatics. switch is usually on the side of the selector lever.

S: Sport Mode: This automatic mode changes up the gears later and lets the engine rev more. this makes the car more sporty but uses more fuel and can be a bit annoying!

That's my understanding of Auto boxes anyway,

_Kaiser_

colm_mcm wrote:

3: 3 Position: This allows the gearbox to select any of the gears up to and including third gear, and locks out 4th gear and overdrive, handy if you're planning some overtaking and saves you the amount of time it takes the box to change down from top gear.

So how would you ideally downshift to this while moving? Foot down on the brakes and drop it into 3? As I mentioned, I only ever really use D

dubtom

O/D: Overdrive Switch: This changes the top gear ratio, handy if you're doing high speed overtaking, the slight increase in engine revs make acceleration better. These switches are being phased out, and are usually fitted to 4 speed automatics. switch is usually on the side of the selector lever.

I've left mine in over drive since I got the car. I find without it the car revs out too soon, rather like screaming for a fifth gear.

So how would you ideally downshift to this while moving? Foot down on the brakes and drop it into 3? As I mentioned, I only ever really use D

Dont need the brake, just put in 3.

colm_mcm

Drive to 3 position isn't protected by a switch, 3 to 2 usually isn't either.

2 to L is protected, because accidental selection of L at high speed will result in you bringing your engine home in a Hoover bag.

You just have to pull the lever back

Note: in newer cars, there isn't a button on the side of the selector
Instead as in this picture, the gear lever has to be moved to the side in order to get the lever to the desired position

Rovi

mike65 wrote:

There's a few things I'm curious about, one is do all auto boxes rev higher when in neutral? Mine goes from 850 to 1000.

Normal. The revs drop when you select a gear because there's a load on the engine.

mike65 wrote:

On the D or N at idle, the Royal Society of the Prevention of Accidents (yes such a thing exists!) says leave car in D, neutral actually causes more wear.

With the ZF HP-22 boxes we use in the off-roaders, we've been warned not to leave them running indefinitely in P. Something to do with the fluid pressure having nowhere to go if it's not engaging a clutch pack somewhere. Leaving them in N is a bit better, but leaving a gear engaged (1, 2, 3, D, or R) is best.
If I'm going to be stationary longer for than I feel like standing on the brakes, I'll either select N or shut the whole thing down.

colm_mcm wrote:

Drive to 3 position isn't protected by a switch, 3 to 2 usually isn't either.

On the ZF boxes, you can shift between D and 3 without using the button, but not originally to any of the other gears. We've removed the notch between 1 and 2 to allow for easy shifting when off-road.

Whether on or off the power, we just shift them into whichever gear is required at that moment. They seem to be able to live with it :rolleyes:
We've also removed all the safety interlocks to allow starting in gear, but that's another story

andrew_ireland

mike65 wrote:

Does your auto "hold" a gear longer when accelerating with cold fluid?

Mike.

I don't know what car you drive but I drive a Nissan Sunny auto and there is an overdrive switch on the stick. Overdrive in the "off" position will cause the car to hold the gear for a longer time, but when it's turned on and the car is started from cold it will hold the gear until it warms up as the box has to warm up before overdrive comes on. I hope that makes some kind of sense!

alias no.9

Selecting 2 or 3 is also useful for backroads with tight and twisty sections where the autobox can change up when you lift off before going around corners. Figured this out with a rental car on the great ocean road in australia when I was getting really pissed off because of the combination of hills and bends, the car would change up when I lifted off coming into a bend, the exit of which would be uphill and the car would be completely gutless meaning I'd have to plant the accelerator to get it to kick down. Selecting 3 sorted it out nicely.

michaelanthony

Mine idles at 900 rpm. The 1 2 3 are for mountain descent and ascent.

Henry Ford III

colm_mcm wrote:

.......N: Neutral: Neutral is usually used when the car is temporarilly stopped, eg. at traffic lights, it prevents the car from creeping (crawling forward when the car is in Drive) If you are in very slow moving traffic going downhill, Neutral can be used. There usually isn't any safety devi ce preventing shifting between "N" and "D".........

Freewheeling in an auto is a big no no, as is towing with the driven wheels on the ground. Both destroy the torque convertor.

Apart from that you are right on the money.

Johnny Storm

FWIW I virtually never use N. The rev counter on my one does not register any change if I move from N to D while stationary. As regards "accelerating with cold fluid" ... well, no car likes to be flogged until its properly warmed up.
I very rarely would change from D to 4 if I wanted to overtake without having it change gear half way through. Usually I put it into Sports mode and this has the same effect.
I'm looking forward to the day when your autobox knows when you want to go backwards and automatically selects R

BTW how come no one has replied yet with the good old "I dont dont like autos 'cos I'm a real man and anyway I've never tried one" malarky?

_Kaiser_

Johnny Storm wrote:

BTW how come no one has replied yet with the good old "I dont dont like autos 'cos I'm a real man and anyway I've never tried one" malarky?

I've been expecting that too, but it's interesting to see that there's more than 2 or 3 of us with an Auto. I reckon they're becoming increasingly popular (and practical) with the traffic and wouldn't ever change to a manual myself, but the aforementioned "real men" will do doubt disagree! :rolleyes:

Villain

I have a 2.5l Subaru Legacy AWD with an Auto Box and I have 3 settings, Normal - Power and Hold.

The Power setting I believe is basically overdrive, the Hold position is for frosty slippy conditions it holds its position for longer and normal is just that normal.

There is 3 automatics in my house, mine, a Nissan Almera 1.6 twin cam and a C180 Coupe and the auto box in all 3 are very different. The Almera's box is awful compared to the other 2, very hard to dictate what gear you want to be in. The Merc's is better and is also triptonic which is a bit of a pain to use to be honest. The subaru by far though has the best auto box although to be honest it just seem better than the merc because it's AWD.

MercMad

There is some good info here but a lot of it is model specific so be careful with that !

For eg. on most Mercedes transmissions it is suggested that you leave it in "D" when at traffic lights, the car will not roll backwards either when in "D".

Also you can tow a short distance "under" 30MPH.

On my CLK you cannot change out of "P" unless your foot is on the brake, nor from "N" into "R" or "P". You cannot remove the ignition key unless the car is in "P" and the button marked "C/S" is for Comfort and Standard (not sport). When in "C" the car does not use 1st gear at all and the changes are slushier and happen earlier. It will not pass 5000RPM unless the kickdown is operated. In any gear it will kickdown under part throttle if it needs to !

However on my 280SE Coupe (1968) the auto for starters is in the reverse plain, i.e "P" is nearest to you with "2" being furthest away. You can actually move it into any gear without operating the brake ! ( Yikes !). It always starts in 2nd gear unless you shift into "2" in which case you get 1st and 2nd only ! Also even though this tranny was used since 1961 it is actually a 4 speed auto !

But the enst thing about this Auto Trans is that you CAN start it with a tow, just like a manual car !!

unkel

I've a 5-speed steptronic box. It's only got P / R / N / D. I usually have it in normal mode. By moving the knob to the left, the steptronic / sport mode is enabled. In this mode you can shift up / down manually too if you want. Even in normal mode you can manipulate the gear shifting quite a bit as someone else mentioned. One clever feature is when going down a hill when you press the brakes while not having your foot on the accelerator, the box "knows" you want to brake on the engine, so shifts down one or two gears

I never use N. When stopped in traffic I always keep it in D and only when I leave the car, I use P. Engine can only be started when gear is in N or P

I sometimes, but not often use the steptronic mode, e.g. just before the NCT when the only way to stay within the speed limits (more or less) in Lucan while revving the engine a bit to heat up the cats was in first gear

The engine idles @550 rpm

Stark

Kaiser2000 wrote:

I've been expecting that too, but it's interesting to see that there's more than 2 or 3 of us with an Auto. I reckon they're becoming increasingly popular (and practical) with the traffic and wouldn't ever change to a manual myself, but the aforementioned "real men" will do doubt disagree! :rolleyes:

I don't have an auto because I'm a real man*

* I don't have the money for one, and I'm an envious onlooker in this thread

Diamondmaker

had an auto 3 months now...Never looked back. I must have gotten one of a very small handfull of BMW Cis in Auto, as over the previous 6 months looking I only came across 3 others!

The sports mode is great for responsive driving and it will not change gears until 6000rpm so you get every last drop out of it similar to pushing your manual to the red.

There is a tip tronic feature that is activated by kicking the gear lever to the left. In this you can manually select gears up and down with out a clutch, great for windy county roads where the manual is traditionally more fun.

I have suffered no draw backs and have not noticed any extra fuel usage over my last similar model MT. I think once you go auto you will never go back, especially one as I mention that really does compensate the sporty driver.

The adavantages during the 80% of time where you cannot be sporty and are stuck in traffic far far far out weigh the odd time you may miss your clutch!
My body aches so much less these days!:D

Bluehair

Diamondmaker wrote:

The adavantages during the 80% of time where you cannot be sporty and are stuck in traffic far far far out weigh the odd time you may miss your clutch!
My body aches so much less these days!:D

Hell yeah, my next bmw is definately doing to be the steptronic for all the above reasons, plus you can retro fit paddle-shift to these for extra fun!

maidhc

Kaiser2000 wrote:

I reckon they're becoming increasingly popular (and practical) with the traffic and wouldn't ever change to a manual myself, but the aforementioned "real men" will do doubt disagree! :rolleyes:

Not only don't real men do autos, they don't do synchromesh manuals or hydraulic clutches either. Double declutching FTW.

Stark

I hope to get a car with continuously variable transmission some day. That sounds cool.

Henry Ford III

Stark wrote:

I hope to get a car with continuously variable transmission some day. That sounds cool.

On the contrary CVT actually sounds cack.

The engine revs up and stays there whilst the transmission matches gearing to speed and load.

It's a very strange experience tbh.

Stark

It's an improving technology afaik. As in not ready for primetime yet but should be once new developments go into production. In theory it sounds very efficient as the engine is always at optimal revs for fuel efficiency. I think new developments will probably be to determine when the engine should be revving at higher than optimal to give extra "oomph".

MercMad

There is a tip tronic feature that is activated by kicking the gear lever to the left. In this you can manually select gears up and down with out a clutch, great for windy county roads where the manual is traditionally more fun

..............seems rather awkward that you would have to 'kick' the gear lever to the left. Most cars nowdays you can just use your hand !

Bloody BMW's

I drove the CVT Audi and hated it, absolutely hated it !!

Also I noticed the latest autos are now not only faster 0-60 (have been for some time now) but they are more frugal too !

unkel

MercMad wrote:

Also I noticed the latest autos are now not only faster 0-60 (have been for some time now) but they are more frugal too !

Yep. A computer can be programmed to be as fast as possible, so it will shift up at optimal points. The only reason the 0-100km/h times are very close for modern cars, is that a professional driver that knows the optimal moments has clocked that time. Most other humans will find it impossible to get the same acceleration as per the tech spec

Autoboxes do not come with a huge weight gain anymore either

The vast majority of cars will be automatic within a decade imho