Manual vs. Automatic Transmission, Advice Needed

[SkyMaster]

A friend of mine has a manual car (Mazda) here and offered to teach me, which I will eventually take up on that offer. Whether or not I end up renting a car, I still think it is worthwhile to at least have a bit of an idea of what it means.

That is generous of your friend.  Or maybe she does not know the cost involved.  At least in my experience, teaching someone to drive a manual transmission always involves serious wear, like 50,000 miles worth, on the clutch.  Sometimes it involves a broken u-joint or damaged cv-joint.

There is no reason to wear or damage a clutch while learning.

I taught to drive manual to a few girl friends, and I always taught to engage first gear without giving any gas. Only once the clutch pedal is fully released that is possible to press on the gas pedal.

Getting moving on an incline come after, and then the technique is to be quick; not to let the clutch slips.

 

[sokoloff]

Distinction between manual and automatic also gets more blurred with the modern "assist" systems like the idle increase based on clutch pedal position, ECU rev matching during gear changes and delay valves on clutch release.

It has been nebulous for a long time.  How would the 50 year old Volkswagen Automatic Stickshift be classified?

Agree that it's hard to put a bright line on things. For my money, if it has a torque convertor, it's an automatic at its core.

[bob91343]

That is a lovely ZF commercial.  It doesn't address what I have heard about them, namely the lousy reliability.  A local  mechanic who speicalizes in BMW said that the ZF automatics keep breaking.  Another specialist told me, about my stick shift, that the transmission will outlast the rest of the car.

Perhaps things have changed since then but for now I will continue to enjoy my 1994 530i stick.  I have so far not needed to do service on the transmission or clutch in nearly 200,000 miles.

[coppice]

How would the 50 year old Volkswagen Automatic Stickshift be classified?

A lot of buses use a similar kind of transmission to that.

[David Hess]

How would the 50 year old Volkswagen Automatic Stickshift be classified?

A lot of buses use a similar kind of transmission to that.

They do allow more driver control than an automatic transmission without requiring a manual clutch.

[sokoloff]

I taught to drive manual to a few girl friends, and I always taught to engage first gear without giving any gas. Only once the clutch pedal is fully released that is possible to press on the gas pedal.

Getting moving on an incline come after, and then the technique is to be quick; not to let the clutch slips.

I taught several as well. One in particular, I was teaching the hill start technique on a pretty serious incline (a ramp up and over some train tracks) in a notably wealthy suburb of Boston (Wellesley). She had a car close behind her and I explained that I'd manage the hand brake for her. She objected and asked "would you use the hand brake if you were driving?" "Nope." "Well, then I'm not either; teach me the right way..." "OK, you're going to want to give it a little extra gas; put the ball of your foot on the brake and use your pinky toe side to rev the car a little; when the light turns green, bring the clutch up a little bit and when you feel it start to catch, less brake, then more gas, and keep the clutch coming up." "OK, got it."

Now, to her credit, she certainly did not roll backwards into the car behind her. This was the days before cell phones and video cameras, but in this quiet, sleepy little New England town, I imagine it looked a little something like this:

[KL27x]

^Well, with those directions, that is a reasonable result.

Here is how I would break down the algorithm, to quote myself. I think it's that good, but maybe I'm wrong.

Another noob mistake I have seen on an upslope is revving the engine up like 4k+ before the clutch even hits the knee. Find the knee and start engaging, first, before you start adding gas. And the engine should never have to rev that high until after the clutch is fully lifted (and I'm talking San Francisco inclines). It can be a little more confusing when uphill where you have to be on the brakes. If in doubt of where the clutch starts to engage just keep slowly raising the clutch until you can hear/feel the engine bog down. At this point, hold the clutch where it is and give a little gas just enough to return the engine to a healthy high idle. You do not need to rev the engine high. Then start rolling off the brake. If the car rolls backwards, no biggie. When first learning, I suggest you immediately hit the brake and stomp the clutch down and completely start over (for the sake of your clutch). Lift the clutch a little higher this time, and give it correspondingly more gas to keep the engine at the same healthy high idle before lifting off the brakes. This is better than burning out the clutch. IOW, if in doubt, I would err towards stalling the motor. You should never have the engine revving much more than a high idle while the car is stationary, unless you want to peel out. And in this case, you would want to "dump" the clutch pretty fast to avoid burning it out.

To be clear, on an upslope you CAN keep the car stationary with just the clutch and the gas pedal, indefinitely. So you can hit this mix before you even let off the brake. Furthermore, you can achieve this with different ratios of gas/revs and clutch. Higher revs and lower engagement, or lower revs and higher engagement. You want to use lower revs and higher engagement. The amount of revs vs the speed is the ultimate feedback. If the car is revving high but not moving, you're burning the clutch.

It is instinctive that higher revs = more power. But when it's not matched to the speed (of zero), there is loss of efficiency in the clutch and/or tire traction. What you want is the same low revs despite giving more gas, by virtue of loading the engine with higher engagement. When on that same hill in an automatic car, the engine won't increase very much in rpm when you let go of the brake, and it won't roll back. But it will be burning more gas and O2. The clutch will be slipping, but at high force and low speed, low heat. Increasing RPM before engaging the clutch just burns the clutch (or tires, if you dump it).

[SkyMaster]

I taught to drive manual to a few girl friends, and I always taught to engage first gear without giving any gas. Only once the clutch pedal is fully released that is possible to press on the gas pedal.

Getting moving on an incline come after, and then the technique is to be quick; not to let the clutch slips.

I taught several as well. One in particular, I was teaching the hill start technique on a pretty serious incline (a ramp up and over some train tracks) in a notably wealthy suburb of Boston (Wellesley). She had a car close behind her and I explained that I'd manage the hand brake for her. She objected and asked "would you use the hand brake if you were driving?" "Nope." "Well, then I'm not either; teach me the right way..." "OK, you're going to want to give it a little extra gas; put the ball of your foot on the brake and use your pinky toe side to rev the car a little; when the light turns green, bring the clutch up a little bit and when you feel it start to catch, less brake, then more gas, and keep the clutch coming up." "OK, got it."

Now, to her credit, she certainly did not roll backwards into the car behind her. This was the days before cell phones and video cameras, but in this quiet, sleepy little New England town, I imagine it looked a little something like this:

When I was 20 years old, I had a 1979 VW Rabbit, just like in the video, but with an engine and a transmission from a 1984 Rabbit GTI (Rabbit was the North American name for the Golf). The car had an exhaust header and a freeflowing exhaust. My advice was "If in doubt, let go the clutch and jump on the gas; as it is easier to replace tires than to replace a clutch". The front tires would spin just like in the video.

And oh, I taught myself to drive manual transmission when I test drove that car before buying it; it was so powerful and fun to drive that I bought it right away.

 

[mzzj]

I taught several as well. One in particular, I was teaching the hill start technique on a pretty serious incline (a ramp up and over some train tracks) in a notably wealthy suburb of Boston (Wellesley). She had a car close behind her and I explained that I'd manage the hand brake for her. She objected and asked "would you use the hand brake if you were driving?" "Nope." "Well, then I'm not either; teach me the right way..." "OK, you're going to want to give it a little extra gas; put the ball of your foot on the brake and use your pinky toe side to rev the car a little; when the light turns green, bring the clutch up a little bit and when you feel it start to catch, less brake, then more gas, and keep the clutch coming up." "OK, got it."

Even better if the car has race-style sinter clutch 
Kinda grabbing especially when cold, on-off action with not much slipping between. 

[emece67]

.

[SparkyFX]

On the practical side, maybe it makes sense to learn driving with a stick shift in a certain order.
Build muscle memory to:
- locate the pedals
- learn how to stop if things go wrong by pressing clutch and brake pedal
- keep a certain RPM reliably with the right foot, either by sound or rev counter
- find the slip point of the clutch
- find the slip point of the clutch while keeping a certain RPM
- find the slip point of the clutch while increasing RPM
- coordinate all that with the use of the parking brake or how to switch fast enough from brake to accelerator pedal

The smaller the car, the less complicated it is, because you need less torque to accelerate it forward.
However, with more recent cars, there might be functions like hill start assist that automatically hold the brake or parking brake and open them once you let the clutch go, so you only need to concentrate on clutch and gas.

While driving, some cars might disengage the cruise control when changing gears, some hold it for while after pressing the clutch (without revving up).

[CatalinaWOW]

There will always be some learning when entering a new vehicle.  Just hope that the first dozen or so starts from wherever you pick up the vehicle are fairly benign. 

[ebastler]

Lastly, for practical purposes am I going to go completely bonkers learning manual at this point, do you have to continually practice it or will it completely fade away, and should I be worried about travelling and renting? Aside from travelling, is it something I want to learn to keep my car experience options open in the future?

Others have mentioned that a trip abroad may not be the best opportunity to gather experience with stick-shift driving -- the different road signs and environment will keep you busy already. Depending on where in Southern Europe you drive, you may also encounter hilly terrain, which adds a few challenges. (Starting a car on an upward slope tends to scare most driving students at first...)

Beyond that, if I may ask: How old are you? When did you last learn a new skill which requires coordination of multiple extremities? (A complex video game maybe, playing a musical instrument, or juggling?) And did you find it easy to get adjusted to these new motion patterns? That may give you an idea whether adjusting to manual gear shifting and the clutch pedal will come easy.

[bw2341]

A lot of the documentation for Toyota's hybrid system refers to the electric power transfer arrangement as a CVT or eCVT. They like to keep changing terminology, like the latest material calling the system a self-charging hybrid.

It is a continuously variable transmission in the same sense that a switching power supply, variable transformer, or motor-generator is a continuously variable transmission which changes the ratio between voltage and current or torque and distance continuously.  It is not a continuously variable transmission as commonly understood to be a mechanical continuously variable transmission so does not suffer from those mechanical limitations.

What Toyota did, at least as I understand it, was take a engine-electric transmission system like would be found in a US diesel train locomotive (diesel-electric) and couple a mechanical transmission between the generator and motor using a pair of differentials.  So the mechanical transmission selects the major gear ratio and the motor-generator continuously varies this ratio between gears using a switching converter (or by adjusting the field voltages?).  The advantage of this system is that the motor-generator only has to handle a fraction of the power instead of all of it with the rest going through the mechanical transmission.  I assume Toyota found this configuration to have a better power to weight and size ratio or better economics than a straight series hybrid engine-electric transmission.

Compared to gasoline car transmissions, the mechanical part of the Toyota Hybrid Synergy Drive is incredibly simple and elegant. Of course, the total hybrid system is very complicated. The YouTube video linked by windsmurf covers the mechanical parts pretty well.

The only transmission element is a single planetary gear set. In brief, a planetary gear set has a sun gear, a planetary carrier, and a ring gear. In a regular automatic transmission, a brake band can stop one of the three elements, which changes the gear ratio of the other two. But what if you can control all three elements independently?

The HSD has a smaller electric motor-generator (MG1) which drives the sun gear. The gas engine drives the planetary carrier. The larger electric motor-generator (MG2) is directly coupled to the drive shaft. MG2 and the drive shaft connect to the ring gear.

Changing the speed and direction of MG1, will change the gear ratio between the gas engine and drive shaft. Since the gas engine, MG1 and MG2 are all computer controlled, you can achieve a wide variety of operating modes. The modes can get complicated as MG1 and MG2 can independently switch between motor and generator operation at any time. Mechanical power can flow in any direction between the three shafts. At the same time, electrical power can flow in any direction between the two MGs and the battery.

The HSD is mechanically simpler than typical car transmissions. There is only a single set of permanently engaged gears. There are no linkages and clutches of a manual. There are no brake bands and actuators of an automatic. There are no electomechanical actuators of a DCT. There are no heavily clamped friction surfaces of a CVT.

Even the reverse gear is missing as MG1 can directly drive the car in reverse. The only traditional element is a parking pawl.

[David Hess]

My advice was "If in doubt, let go the clutch and jump on the gas; as it is easier to replace tires than to replace a clutch".

I received similar advice about engine braking using a manual transmission and letting the clutch slip too much.  "Brake pads are much less expensive to replace than clutches.  Slip the clutch less."

On the practical side, maybe it makes sense to learn driving with a stick shift in a certain order.
Build muscle memory to:
- locate the pedals
- learn how to stop if things go wrong by pressing clutch and brake pedal
- keep a certain RPM reliably with the right foot, either by sound or rev counter
- find the slip point of the clutch
- find the slip point of the clutch while keeping a certain RPM
- find the slip point of the clutch while increasing RPM
- coordinate all that with the use of the parking brake or how to switch fast enough from brake to accelerator pedal

This can have unfortunate results if you operate an automatic transmission after becoming very used to a manual transmission.  You can end up pushing on the clutch (edge of the brake pedal) as you stop, noticing that you are stopping faster so much not have disengaged the clutch so you push harder on the clutch (edge of the brake pedal), and repeating with the result of pushing the clutch (edge of the brake pedal) to the floor locking the brakes and surprising those around you.

...

So I got the essence right.  I had forgotten that the motor/generators were tied to the planetary gears directly but that makes sense as a mechanical simplification.

It is a clever system and optimization to be sure.  I am just dubious of anything which when automated becomes an additional point of failure and doubly so with anything from a car company.

[sokoloff]

[HSD] is a clever system and optimization to be sure.  I am just dubious of anything which when automated becomes an additional point of failure and doubly so with anything from a car company.

I share your general philosophy, but HSD has been out for quite some time and by all accounts has phenomenally long and trouble-free service history. Several Prii have exceeded 500K miles, some in taxi service, so at this point I’d feel totally fine about buying or driving a high-mile Prius.

[NiHaoMike]

This can have unfortunate results if you operate an automatic transmission after becoming very used to a manual transmission.  You can end up pushing on the clutch (edge of the brake pedal) as you stop, noticing that you are stopping faster so much not have disengaged the clutch so you push harder on the clutch (edge of the brake pedal), and repeating with the result of pushing the clutch (edge of the brake pedal) to the floor locking the brakes and surprising those around you.

I wonder how difficult it would be to put in a "clutch emulation pedal" that basically just tells the drivetrain to "not apply any torque to the wheels", including minimizing mechanical resistance unless the brake pedal is being pressed.

Compared to gasoline car transmissions, the mechanical part of the Toyota Hybrid Synergy Drive is incredibly simple and elegant. Of course, the total hybrid system is very complicated.

It is a clever system and optimization to be sure.  I am just dubious of anything which when automated becomes an additional point of failure and doubly so with anything from a car company.

The majority of the complexity is indeed in the (very reliable) electronics. Some DIY EV hackers have tried to reverse engineer the inverter module but were not able to figure out the custom ASICs that were used. Some very early 1st gen inverters (Japanese market and rare) used FPGAs and I remember reading about the 4th gen going back to FPGAs because they got cheap enough that the savings from making a new custom ASIC was no longer worth the risk. The IP protection would likely prevent any real reverse engineering, but I suppose that does open up the possibility (albeit low due to the complexity) for the DIY EV hackers to create an open source firmware to reuse the inverters in DIY EVs.

[ebastler]

This can have unfortunate results if you operate an automatic transmission after becoming very used to a manual transmission.  You can end up pushing on the clutch (edge of the brake pedal) as you stop, noticing that you are stopping faster so much not have disengaged the clutch so you push harder on the clutch (edge of the brake pedal), and repeating with the result of pushing the clutch (edge of the brake pedal) to the floor locking the brakes and surprising those around you.

Since I always drive stick-shift cars at home, and automatics when renting a car in the US, I can confirm that an attempt to hit the non-existent clutch is a likely "failure mode".   

It does not even take a conscious (or subconscious) cycle of "hey, this thing is slowing down too fast, I must step on the clutch harder". If you want to brake and stop from a slowish speed in a stick-shift car, you will "floor" the clutch pedal to release the clutch, while gently dosing the brake. Not good if you floor the brake pedal instead, since there is no clutch...

[mfro]

I may be in Europe some time in the near future and possibly renting a car.

Where in Europe? Depending on country and region, things might be different.

If you go to some industrial area, you most likely get an auto without asking anyway, because that's what they have. Where I live, for example, most rentals are DCTs nowadays (there are Germans as well that never drove a stick and have a limited license that only allows them to drive auto).

Should there be a choice, any reasonably alert agent will give you an auto in his own best interest as soon as he realises you are American (as he doesn't want you to break their car because of lack of experience).
Things might be different if you go to more rural areas, however.

Frankly, if I were you, this would probably be the least thing I'd worry about. Rather make sure you do not pay a huge uplift if you intend to return your car in a different country than you got it, for example.

[vk6zgo]

This can have unfortunate results if you operate an automatic transmission after becoming very used to a manual transmission.  You can end up pushing on the clutch (edge of the brake pedal) as you stop, noticing that you are stopping faster so much not have disengaged the clutch so you push harder on the clutch (edge of the brake pedal), and repeating with the result of pushing the clutch (edge of the brake pedal) to the floor locking the brakes and surprising those around you.

Since I always drive stick-shift cars at home, and automatics when renting a car in the US, I can confirm that an attempt to hit the non-existent clutch is a likely "failure mode".   

It does not even take a conscious (or subconscious) cycle of "hey, this thing is slowing down too fast, I must step on the clutch harder". If you want to brake and stop from a slowish speed in a stick-shift car, you will "floor" the clutch pedal to release the clutch, while gently dosing the brake. Not good if you floor the brake pedal instead, since there is no clutch...

I ran into that problem many years back, when it was the habit amongst car makers to provide huge brake pedals so people could use "left foot braking".
With all the automatic cars I've driven since then, the brake pedal is very little, if at all, larger than those for manual vehicles.

Do they still install the huge pedals in the USA?

[sokoloff]

In some cars, yes. More than a few times, I've mashed my left foot onto a firm brake pedal when getting ready to start an automatic-equipped rental car.

[garethw]

Manual gearboxes are the default here in the UK. Having said that, automatics are becoming increasingly more popular. I drove a manual for over a decade and used to think that automatics weren't "real driving". That was until I got an automatic! I can now honestly say that I will not go back to a manual. I've had a Honda with a robotised gearbox (a manual box with a robot that controls the clutch and gears) and now drive a VW van with DCT. The Honda gearbox was....lets put it this way, Honda scrapped it after a few years of production.
The DCT in the van is great. Yes, it doesn't always pre-select the right gear as it has to predict the next change and unfortunately nothing short of a neural connection to your brain will predict if you suddenly change your mind at roundabout and boot it. My only genuine concerns with the DCT are reliability and repair costs.

I always tell people that the future is automatic seeing as though electric cars don't have manual gearboxes.

[sokoloff]

I always tell people that the future is automatic seeing as though electric cars don't have manual gearboxes.

Are there any electrics with gearboxes at all (ones with multiple, selectable gear ratios)? My LEAF doesn't have one and I'm not aware of any others that do.

[garethw]

When I say "Automatic" i mean not manual.
Electric cars don't have a gearbox as the motors are directly coupled to the wheels, however as a driver, the controls are similar to a simple automatic i.e. Neutral, forwards or reverse. Also, there are only two pedals for everything except a manual.

[mzzj]

I always tell people that the future is automatic seeing as though electric cars don't have manual gearboxes.

Are there any electrics with gearboxes at all (ones with multiple, selectable gear ratios)? My LEAF doesn't have one and I'm not aware of any others that do.

BMW i8 
https://gas2.org/2014/11/12/gkns-two-speed-eaxle-boosts-ev-performance/

Tesla attempted 2-speed gearbox also with the roadster but they were under-engineered and failure-prone.

Real direct driven wheels are rarity in electric cars, difficult to make enough torque in compact size.