Downshifting in ATX manual mode

[the-k-man]

I have a question about the manual mode with the automatic transmission for an 04 sedan. When coming to a stop like at a red light, should i be downshifting myself at all, or should i let the tranny computer do it for me? I remember reading from somewhere that it has less wear on the tranny if i let it downshift by itself.. can anyone fill me in on the proper method?

thanks!

[S.F.W.]

not sure, but my logic says, if you are going to have the car auto down shift, why not just leave it in automatic?

[Mazda3_06]

i let it go by itself

[Chuckie]

downshifting is overrated.
I don't downshift when I know I have to stop.

[majic]

if you want to down shift, get a car with a manual transmission.. if you got the ATX then just let the car do its thing..

[Skarbro]

+1. Don't expect any benefit from downshifting manually in an automatic to a stop. Just let the auto tranny do it for you.

Although, I can understand downshifting if you are anticipating an eminent need for the lower gear - i.e., rounding a corner quickly.

[Kevin@nextmod]

Downshifting on ATX or MTX will dmg your gears in the long run because of the heavy stress. BUT if you are doing heal toe or rev and match then that will not be a problem. But only if you're very used to doing it or doing it often, or else just let the tranny do its job.

And You can rev and match with ATX, trust me.

[stas]

the only time i downshift is when i need to be in higher rpms after the turn or when i pass someone, honestly there is absolutely no point of downshifting. unless ofcourse you wish to engine-break in an emergency or on a very slippery surface.

there is also no point of downshifting with a manual in regular situations

[Skarbro]

there is also no point of downshifting with a manual in regular situations
+1 also.

http://www.edmunds.com/advice/youngdrivers/articles/116920/article.html


Myth #3: Use the clutch to save your brakes.
The clutch can theoretically be used as a braking device when slowing down, but this is more trouble than it's worth. First, if you're using the clutch to slow a car to "save your brakes" you better be really good with the clutch. If you're not smooth in your downshifting you'll be putting extra wear on the clutch.

Anyone want to guess which components cost more to replace — brake pads or a clutch plate? You're better off just pushing the clutch pedal in and leaving it in, and/or shifting to neutral, when slowing down in a manual-shift vehicle — especially if you aren't extremely smooth at downshifting. If you are smooth at downshifting and you feel like going through the trouble, you can constantly downshift and release the clutch as you slow down. But even doing that action smoothly won't make your brakes last appreciably longer.

[majic]

You're better off just pushing the clutch pedal in and leaving it in, and/or shifting to neutral, when slowing down in a manual-shift vehicle

that's what i do..

[derrick]

As others have said there is no point downshifting when coming to a complete stop. I do downshift when I expect to slow down but not have to stop.

Yes you can revmatch to a point with the automatic, but its not the same as a manual. You get on the gas slightly and then downshift. If you don't feel the shift shock then you were successful.

There sure are a lot of automatic haters in Toronto apparently. This is the second thread I have read in the last 2 minutes where peoples solutions to anything related to an automatic transmission is to get a manual.

Well I drive through rush hour traffic daily for at least an hour a day and I love the fact that I can put the car into drive and let it idle all the way home. Sure manual would be nice, but the tiptronic transmission is a good compromise. And it works fine for me in autox.

[stas]

+1 on traffic

[Skarbro]

Yes you can revmatch to a point with the automatic, but its not the same as a manual. You get on the gas slightly and then downshift. If you don't feel the shift shock then you were successful.


I don't understand this. Why would you want to try to rev-match in an auto? There is no manual clutch, so you can't rev up the transmission without putting more spin to the wheels at the same time.

Oh and no auto-hating here. I respect auto drivers. ;)

[derrick]

Well because there is a delay between getting into gear, yes even on an automatic, if you are on the gas while you tell it to shift, it will rev match to a point.

There is no real reason to do it except that it is smoother. I have used it occasionally when it has been a late night and I am driving somebody home who happens to be napping in the car.

Not saying you have to do it. Just saying it is possible.

[majic]

There sure are a lot of automatic haters in Toronto apparently. This is the second thread I have read in the last 2 minutes where peoples solutions to anything related to an automatic transmission is to get a manual.

Well I drive through rush hour traffic daily for at least an hour a day and I love the fact that I can put the car into drive and let it idle all the way home. Sure manual would be nice, but the tiptronic transmission is a good compromise. And it works fine for me in autox.

it's not that we're hators.. a lot of people buy ATX and try using it as if it were MTX which simply makes no sense ..

i drive 50km each way in traffic and the MTX fares just fine.. so does my leg.. ;)

[3GFX]

I would have prefered an ATX but...yada yada yada...I ended up with the ATX.

I like to let the car downshift in manual mode because it does it very smoothly. I have the 4spd and I noticed that when downshifting for itself the tranny goes from 4 - 3, 3 - 1. No idea why, but its smooth like zambonied ice when it does it.

As for why use the Manual mode in our ATX?
- It allows you to hang on to a gear, right to the redline
- You can short shift and gain gas milage
- Sometimes you just wanna hear it sing!

[Kevin@nextmod]

and it sounds better when you downshift on your own.

[derrick]

it's not that we're hators.. a lot of people buy ATX and try using it as if it were MTX which simply makes no sense ..

i drive 50km each way in traffic and the MTX fares just fine.. so does my leg.. ;)

Crawling traffic at 15-20km/h for 50km is very different from driving 50km. I've done it and you either tire your leg out or burn your clutch to a steaming pile of crud.

[Skarbro]

Crawling traffic at 15-20km/h for 50km is very different from driving 50km. I've done it and you either tire your leg out or burn your clutch to a steaming pile of crud.

Honestly I don't see what the big deal is. Driving stick in stop-and-go traffic (15-20 km/h) is no big deal at all (we have the busiest stretch of highway in the world in Toronto). I've never tired out me leg with the clutch. Sure there is a little wear on the clutch, but there's wear on an auto transmission too in that kind of traffic. Definitely, driving auto in those circumstances is easier - but driving stick in those same situations is by no means difficult or a nuisance (it's the damned traffic that's a nuisance!! ;) ).

[Wild Weasel]

That's actually bad advice you posted from Edmonds and may actually be illegal in some states.

Downshifting doesn't just save you some inexpensive brake wear. It also puts you in the proper gear for the speed you're doing and leaves you with continual control over the car.

Shifting to neutral or just putting the clutch in while coming to a stop is flat-out wrong. If you're not going to downshift, you should just leave it in gear until you get down to your idle RPM. Even if you're in a high gear, you're still getting some benefit from engine braking and you're saving gas, to boot.

Downshifting isn't about saving brakes. That's just a small and arguably trivial side-effect. It's about properly controlling the car and being prepared for any situation that may arise.

[Skarbro]

That's actually bad advice you posted from Edmonds and may actually be illegal in some states.

Downshifting doesn't just save you some inexpensive brake wear. It also puts you in the proper gear for the speed you're doing and leaves you with continual control over the car.

Shifting to neutral or just putting the clutch in while coming to a stop is flat-out wrong. If you're not going to downshift, you should just leave it in gear until you get down to your idle RPM. Even if you're in a high gear, you're still getting some benefit from engine braking and you're saving gas, to boot.

Downshifting isn't about saving brakes. That's just a small and arguably trivial side-effect. It's about properly controlling the car and being prepared for any situation that may arise.

We're talking about coming to a stop - like when you KNOW you are going to stop because there are cars stopped at a red light for example (at least that's what I'm talking about). In that situation, you won't need a lower gear because your stopping no matter what. Just ride in whatever gear you're in with the brake.

But in a situation where you might need the lower gear, then yes, I agree with you. I've always downshifted if I think I might need the gear, and it is the proper way to do it.

However, I'm not sure why you posted this:



Shifting to neutral or just putting the clutch in while coming to a stop is flat-out wrong. If you're not going to downshift, you should just leave it in gear until you get down to your idle RPM. Even if you're in a high gear, you're still getting some benefit from engine braking and you're saving gas, to boot.

Who said anything about shifting into neutral or depressing the clutch to a stop? That would be stupid.

And how do you save gas by engine braking? Not following you on that statement.

[Wild Weasel]

Who said anything about shifting into neutral or depressing the clutch to a stop? That would be stupid.

And how do you save gas by engine braking? Not following you on that statement.

Your quote says this:



You're better off just pushing the clutch pedal in and leaving it in, and/or shifting to neutral, when slowing down in a manual-shift vehicle — especially if you aren't extremely smooth at downshifting.


As I said... even when you know you are going to stop, you should leave it in gear until your get down to just above idle RPM's. Once you get to idle RPM, then you put the clutch in or the ECU will start sending fuel to bring the revs up and try to accelerate the car in the process.

You save gas because when you're decellerating, the TPS tells the computer you're giving 0% throttle. The ECU sees this and the fact that your RPM's are above idle and cuts out the fuel. All of it. While engine braking, you're getting 0L/100km's. If you shift to neutral or put the clutch in, the ECU has to send fuel to hold idle so you use more gas.

[Skarbro]

Your quote says this:



As I said... even when you know you are going to stop, you should leave it in gear until your get down to just above idle RPM's. Once you get to idle RPM, then you put the clutch in or the ECU will start sending fuel to bring the revs up and try to accelerate the car in the process.

You save gas because when you're decellerating, the TPS tells the computer you're giving 0% throttle. The ECU sees this and the fact that your RPM's are above idle and cuts out the fuel. All of it. While engine braking, you're getting 0L/100km's. If you shift to neutral or put the clutch in, the ECU has to send fuel to hold idle so you use more gas.

Well I'll be... I guess I mis-read that exerpt because that's not the way it was in my head. I agree with you that dropping the clutch all the way while decelerating or shifting to neutral all the way is dumb.

But on the topic of saving fuel - I have to steal a quote from you :D :


That's just a small and arguably trivial side-effect.

[majic]

Shifting to neutral or just putting the clutch in while coming to a stop is flat-out wrong. If you're not going to downshift, you should just leave it in gear until you get down to your idle RPM. Even if you're in a high gear, you're still getting some benefit from engine braking and you're saving gas, to boot.

come again!??!?!

how is it flat out WRONG? the OP asked:


When coming to a stop like at a red light, should i be downshifting

he's not looking to control the car.. if you have an ATX then you mash the pedal and MOST of the time find yourself in the right gear to accelerate..

secondly.. HOW are you saving gas? if anything you're actually WASTING gas.. say you're cruising at 2500RPM and decide 'oh i want to stop soon' so you downshift.. what do you do when you downshift? you rev match and i'm sure you know that you blip the throttle so now you're at about the same speed but at say 3500RPM.. engine is spinning faster.. now you probably took the foot off the accelerator .. ok great, you're not suppling the engine with more fuel... until your NEXT downshift.. and the next and again..

now if you press the clutch in or throw it in neutral, you'll get a slight blip and then revs will go down to ~750RPM allowing you to coast even further.. (once i was able to coast for 2.1km around ford drive until i was forced to stop due to gridlock, that's 2.1km of 'free' driving ;)

[majic]

Who said anything about shifting into neutral or depressing the clutch to a stop? That would be stupid.


why?

[Skarbro]

why?

Why ride in neutral or with the clutch in when you can use the engine to assist in braking? Any gear take some burden off the brakes.

[majic]

it depends on the situation.. when you ride in neutral (same as clutch in) you get much more 'coasting' distance compared to the engine braking.. if fuel efficiency is important then this is a great way to go from a light to light.. why brake when it's red and about to turn green?

also, what's cheaper to replace? pads/rotors from regular wear or the clutch from potentially missed shifts?

[Skarbro]

it depends on the situation.. when you ride in neutral (same as clutch in) you get much more 'coasting' distance compared to the engine braking.. if fuel efficiency is important then this is a great way to go from a light to light.. why brake when it's red and about to turn green?

also, what's cheaper to replace? pads/rotors from regular wear or the clutch from potentially missed shifts?

Well I'm not talking about downshifting. I'm just saying if you are in say 4th gear and the light turns red 50 metres in front of you, then just leave it in 4th and don't put the clutch in until just before you stop and stall the car. So you're not missing any shifts and not wearing the clutch at all. You are saving the brakes though.

[majic]

ok.. we're confusing 3 issues here

1) coasting in neutral [me]
2) engine braking in the same gear you started out in (no down shifting necessary) [skarb]
3) down shifting from the gear you started all the way to 2nd? 1st? - in our cars 1st gear is VERY touchy and should really only be used to start the car ;) [weasel]

[Wild Weasel]

First off, let me clarify that all my comments have to do with a manual tranny. I know the thread started off being about the ATX but Scarbro's post quoting Edmonds was about the MTX and that's what I was referring to with my comments.

IMHO, if you've got an ATX, just let it do it's thing and stop pretending you're Mario Andretti. If you wanted a manual, you should have bought a manual. :)

With a manual, the amount of gas needed to bring the RPM's up to downshift is trivial. It takes very little gas to spin up a free-wheeling motor.

If you're timing things correctly so you don't have to stop at all, then you're good to go. That's the best way to save gas.

If you know you have to stop though, coasting to the stop in neutral is not saving you gas and is illegal in some states. At the very least, you should simply stay in the gear you were in until you nearly come to a stop. Then you'll have the benefit of engine braking and will be saving gas while your rpm's are above idle speeds. When they near idle speeds, the ECU will start sending fuel again to prevent stalling. That's when you put the clutch in and stop.

If you downshift, then you'll always be in a position to accelerate if you need to, just as you are with an ATX. As mentioned, when you mash the pedal with an ATX, it will pick the right gear and you'll go. You should have this same option with the MTX. It's just good driving habit.

There's no need to downshift to 1st. As mentioned, the only time you really need 1st is if you're stopped. You can downshift to it easily by double clutching but it's not worth the effort. There's no benefit.

I'm not sure where coasting in neutral came into the discussion. When is this desirable? If you're driving down a mountain and want to save gas, you'll save more gas by staying in gear than by coasting in neutral. See my above comments for the explanation.

[the-k-man]

thank you for the lengthy discussion guys, i think i've learned quite a bit ;)

[Kevin@nextmod]

As my prof always say, "its always easier to change your brakes on the road then your clutch" If that had to do with anything.

Anyways lets move on.

[Biscuit]

I'm going to agree with weasel on this, minus the double clutching to first part. For what reason anyone would be double clutching in a synchronized transmission is beyond comprehension. There is a synchro gear in the tranny to allow you to pick whatever gear your heart desires at what speed you want by simply depressing the clutch pedal. Only in trucks where their transmissions are non-sychronized do you have to double clutch ever!!!! As for toe-heeling, unless you're at close to red-line racing your car would you need to toe-heel so you don't jerk your car uncontrollably and go spinning off the course (or street if your a complete moron).

1. you shouldn't be revving your engine high in the city anyways
2. downshifting at high rpms will wear your clutch out faster simply due to friction
3. you don't have to, stressing have to, rev match when you down shift though doing so will somewhat lessen the pressure off of your clutch plates, but isn't going to signicantly wear your clutch out any faster doing so at 3000 rpm for example than regular driving

[stas]

1. you shouldn't be revving your engine high in the city anyways


......but we all know there are times when you have to.

[Wild Weasel]

I'm going to agree with weasel on this, minus the double clutching to first part. For what reason anyone would be double clutching in a synchronized transmission is beyond comprehension. There is a synchro gear in the tranny to allow you to pick whatever gear your heart desires at what speed you want by simply depressing the clutch pedal. Only in trucks where their transmissions are non-sychronized do you have to double clutch ever!!!!

Not true. You're right in that the synchros are there to allow you to be able to force it into gear. You certainly CAN force it into gear if you try hard enough. But try it sometime and you'll find that it's hard to jam the shifter into first when downshifting.

Now try it again but double-clutching it. The shifter will glide right in like it does any other gear and save some wear and tear on your synchros.

The reason is that 1st is such a low gear that you really have to spin up the gears to synch it up. You can do it with the synchros, or you can do it with the engine and the engine is much easier.

With all that said though... I'm not suggesting anyone actually downshift to 1st when coming to a stop. It's just not worth the effort.

[Xerox]

Not true. You're right in that the synchros are there to allow you to be able to force it into gear. You certainly CAN force it into gear if you try hard enough. But try it sometime and you'll find that it's hard to jam the shifter into first when downshifting.

Now try it again but double-clutching it. The shifter will glide right in like it does any other gear and save some wear and tear on your synchros.

The reason is that 1st is such a low gear that you really have to spin up the gears to synch it up. You can do it with the synchros, or you can do it with the engine and the engine is much easier.

With all that said though... I'm not suggesting anyone actually downshift to 1st when coming to a stop. It's just not worth the effort.

I agree with Weasel. The Synchros are there so that double-clutching is not required but it definately helps. I always double clutch when shifting in cold temperatures when tranny oil hasn't warmed up yet so the synchros don't mesh properly. And also double clutch when I shift into 1st when going about 5km/h (and don't feel like riding the clutch in 2nd) in stop-and-go traffic. And this is with double-cone synchros between first and second.

Please don't flame me if this isn't the way you drive.
I always find that threads talking about how manuals should be driven sometimes get personal. Oh well...it just shows that everyone drives differently. ;)

[Wild Weasel]

I actually do the same when driving in traffic like that. It just didn't occur to me until you said it.

Basically... if I decide that I'm going slow enough and would rather be in 1st, I'll double-clutch it out of habit. It's just easier.

Never when slowing down to stop though. Not worth the effort.

[wtom]

Basically... if I decide that I'm going slow enough and would rather be in 1st, I'll double-clutch it out of habit. It's just easier.

Never when slowing down to stop though. Not worth the effort.


Plus1 ... especially in traffic like this morning where everyone was crawling on the highways.

[Biscuit]

Not true. You're right in that the synchros are there to allow you to be able to force it into gear. You certainly CAN force it into gear if you try hard enough. But try it sometime and you'll find that it's hard to jam the shifter into first when downshifting.

Now try it again but double-clutching it. The shifter will glide right in like it does any other gear and save some wear and tear on your synchros.

Not that I'm flaming you or anyone for that matter, but I very much disagree. And as much as i appreciate the lesson I would like to clarify one thing. I DON'T, but CAN downshift into first with absolute ease, and have always been able to. If you are having problems doing so you might want to bring your car in to have it looked at. Out of curiosity do you also clutch brake at a stop before selecting a gear? Once again not flaming, just curious.

[iconicrocket]

I'm alittle confused, I have a ATX sedan.

Is it OK to put it in neutral while stopped at the lights?

Is it OK to put it in neutral while you're coasting down a hill?

[Wild Weasel]

I'm alittle confused, I have a ATX sedan.

Is it OK to put it in neutral while stopped at the lights?

Is it OK to put it in neutral while you're coasting down a hill?

Yes, it's ok to put it in neutral while stopped at lights but it's stupid and pointless.

It is NOT ok to coast down hills in neutral.

[Skarbro]

What reason would there be to put an automatic in neutral at a stop light?

[stas]

What reason would there be to put an automatic in neutral at a stop light?

when theres a long red light feet get tired to hold press down on the break, hence neutral and ebreak (if there is a slope ) haha

and yes, when you are tired and you've been driving for a long time in stop and go traffic sometimes its nice to relax your feet for a minute.

[3GFX]

Putting the car in neutral reduces stress on the engine because its not working against the brakes. You'll notice your rpm will decrease. Maybe in the long run it would reduce wear from stresses on the engine, but in the end its pointless.

I used to do it in moms accord once in a while in the winter because it had a rough idle sitting a stop lights sometimes.

[Chiburashka]

when theres a long red light feet get tired to hold press down on the break, hence neutral and ebreak (if there is a slope ) haha

and yes, when you are tired and you've been driving for a long time in stop and go traffic sometimes its nice to relax your feet for a minute.

I always do this when i'm tired I put it in neutral and wait, and if it's a slope and the car starts to roll then I put the Ebreak on and just relax. Also riding neutral downhill vs being in D without pressing gas you accelerate faster on neutral. Also if you're at 190 on the highway (hypothetically speaking of course) and you put it in neutral is actually picks up speed for a little while as opposed to letting the computer slow you down.

[iconicrocket]

Putting the car in neutral reduces stress on the engine because its not working against the brakes. You'll notice your rpm will decrease. Maybe in the long run it would reduce wear from stresses on the engine, but in the end its pointless.

I used to do it in moms accord once in a while in the winter because it had a rough idle sitting a stop lights sometimes.

Exactly, I noticed the engine is working harder when I put it in Drive, but the car idles better when I'm in neutral, with a lower rpm.

Going downhill on neutral is dicy, since putting it back in drive will make the engine rpm shoot up like mad as it tries to synchronizes with the transmission.

[Skarbro]

when theres a long red light feet get tired to hold press down on the break, hence neutral and ebreak (if there is a slope ) haha

and yes, when you are tired and you've been driving for a long time in stop and go traffic sometimes its nice to relax your feet for a minute.

Then why don't you just use P?

[Skarbro]

I always do this when i'm tired I put it in neutral and wait, and if it's a slope and the car starts to roll then I put the Ebreak on and just relax. Also riding neutral downhill vs being in D without pressing gas you accelerate faster on neutral. Also if you're at 190 on the highway (hypothetically speaking of course) and you put it in neutral is actually picks up speed for a little while as opposed to letting the computer slow you down.

The computer has no ability to slow you down. It's the gearing that slows the car down.

I'm glad you said hypothetically because putting the car in neutral in that situation is just plain dangerous and stupid. Hell driving at 190 on the highway is just plain dangerous and stupid.

[stas]

Then why don't you just use P?

in my case its mainly because its faster to put it in D when you put it in neutral, plus you got to go throught the entire maze to get it in P, gets on your nerves after a while.

wouldn't it harm your tranny to put it in D from neutral when you are driving at any speed? after all it is auto and they are "dumb".