Automatic Transmission Drag Kills Stop and Go Gas Mileage

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On virtually every automatic transmission car, while in stop and go driving, it is necessary for the driver to ride the brake to keep the car stationary or at speeds lower than approximately 10 mph.
This is because the transmission couples at idle speeds instead of going into a neutral condition. This self propulsion occurs whenever the drive range is selected, even though no pressure is applied to the gas pedal.
When the engine has to idle against this braking drag, the engine has to work harder than if it were a no load idle. A byproduct of this undesirable drag is increased fuel consumption as well as increased engine and transmission heat. It might even cause a few accidents when the car pulls into a slow car in front if the driver day dreams or his braking foot gets too tired.
So why don't the automakers develop an automatic transmission that does not pull the car when the engine idles and there is no pressure on the gas pedal? I think its possible to do this because Toyota had a CVT transmission that was perfect until testers complained it was too different from regular hydraulic transmissions. So, Toyota made the CVT pull just like all the others do. That proves Toyota is just as stupid as anybody else in the business.
This is No. 27 of 1001 improvements desperately needed.
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HERE WE GO AGAIN>>>>>> :(

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Smarter drivers than you shift into neutral on long stops. Your foot should still be on the brakes to keep you at the same location.
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Like my father used to say, "Ideas are a dime a dozen." Nomen's "ideas" are often born from ignorance of the details and frustration in not being able to execute ideas in his personal life. That's just my opinion.
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Nomen Nescio wrote:

stopped. The Hybrid Silverado was a testbed for this and it will be incorporated into most models soon.
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Oh God no.
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Joseph J. Pfeiffer, Jr., Ph.D. Phone -- (505) 646-1605
Department of Computer Science FAX -- (505) 646-1002
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GM doesn't know anything.
Larry Behold Beware Believe
| | <snip> | | Thats why new cars in a couple years will shut the engine off when your | stopped. The Hybrid Silverado was a testbed for this and it will be | incorporated into most models soon. |
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Nomen Nescio wrote:
Sorry for feeding the troll, but I challenge anyone to design a tranny control algorithm for re-engagement following the complete-dropout-at-idle that can adequately handle *both* of the following to the satisfaction of the consumer: (1) A smooth start with light application of throttle for gradual old lady takeoff from stopped, *AND* (2) A sudden pedal-to-the-floor start without effectively simulating a high rev. neutral drop.
Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')
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(1) would be easy enough -- light throttle application would give a properly designed torque converter (i.e., one designed for releasing into a free-wheeling mode while stopped and for re-engaging smoothly) ample opportunity to gently re-engage with nothing more than a light shift sensation such as any other upshift sensation might create.
(2) would be easy with drive-by-wire. Giving the computer full control of the vehicle lets the manufacturer design in behaviors they couldn't otherwise. With the computer in full control of the throttle, the driver flooring it from a standstill would cause the torque converter to re-engage as quickly as it is designed to re-engage -- at whatever throttle opening the computer deems reasonable -- followed by the computer ordering a rapid opening of the throttle to fully open. With drive-by-wire, competent programming and a competent transmission, this could be done amazingly fast.
I guess he had a more workable idea than you would have guessed...

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Marc wrote:

Your solution for (2) would either give a slamming effect or cause a perceptable delay in response. With the present system power train slack already taken up and engaged, acceleration could start immediately with no slam of engagement - quicker than the drive-by-wire. Maybe it could be made "quick enough", but never quite as quick.
Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')
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Check out the latest transmissions, Bill. Look at how smoothly computer-controlled automatic-shifting manual transmissions engage the clutch and shift. I've no doubt an automatic transmission's torque converter can be similarly controlled to engage and disengage, even more easily since it's got the benefit of hydraulics to dampen help smooth things out.
We may never see such torque converters, though, if the automatic-shifting manual transmissions start replacing traditional automatics entirely.
For example, check out the VW group's six-speed direct-shift gearbox in the Audi A3, a hatchback sedan priced only in the $25,000-$30,000 range. This transmission is also available in the VW Golf. You can click off lightning-fast upshifts and downshifts with the F1-style paddles or let it shift itself with smoothness that easily rivals an automatic.
Google "DSG" and you can read up on it. I found this quote: --"The transmission also has a system that apes Formula 1 'launch control'. Keep your left foot on the brake. Select 'Sport' mode on the transmission quadrant. Switch off the ESP. Floor the throttle. The engine then revs to 3,200rpm, where it develops peak torque, but no more. All you have to do is slide your left foot off the brake but keep the right fully planted and you take off, redlining through all six gears if you have the space. But because you have set off at comparatively low revs and because of the way the twin wet clutches work, you could if you wanted to do this repeatedly without straining or overheating the box."--
I bet that once you get a direct-shift gearbox you won't want any other transmission -- why bother with a torque converter at all? Fortunately we're seeing transmissions like these more and more due to the power and efficiency benefits.

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Your wrong there.

Agreed. Why, when a properly designed dry clutch and a fully manual transmission is superior in every way.
Of course, it takes skillful drivers to operate, which the majority of the American public aren't - which is why we get stuck with the mess of mechanical misconceptions like your VW transmission.

Fortunate if your a trans repair shop. For everyone else, the slight savings in mileage will be offset by the cost to repair the things when they break down, which will be often once they go past the woefully short warranty period.
Ted
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Do you have the doom-and-gloom response about other technologies like antilock brake systems, traction control, active suspension, etc.? I imagine there were people having that reaction about disc brakes once upon a time. For my part, I'll reserve judgement on their reliability until we see statistics.
What *does* bother me a bit about all these new technologies is that they require greater and greater control of the vehicle by the computer. How long will it be before you start receiving traffic tickets in the mail because your own car's computer notified the police department that you were doing 78 in a 70 zone? Or how long before your car's computer refuses to allow the vehicle to exceed the posted speed limit? Or how long before police departments start using GPS data to send out speeding tickets, or before the insurance companies increase your rate because GPS data indicates you regularly exceed speed limits? That could all just be paranoia but it's all easily conceivable given the revenue it represents for governments and insurance companies and so forth.
Manual transmissions are great but they also require constant management by the driver, which is why most people don't buy them. I love manual transmissions but the two cars we own are automatics, partly because they're both Durangos, but also because they're daily commuter vehicles and passenger carriers where manual transmissions get a bit tedious. If I could afford a third car as a fun/weekends kinda vehicle I'd get a manual.

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Sure:
ABS: Does nothing but get you rear-ended. This has been thrashed out in this forum before. Yes- ABS will allow morons who don't know how to brake, get the maximum stopping distance on ice, by just slamming down on the brakes. No, it will not help when the guy behind you, who does not have ABS, cannot match your rapid decelleration on ice and smashes into you. It makes it a lot more expensive to service the brake system as you can't bleed air out of it without a scan tool.
Note: I have ABS on 2 of my vehicles, BTW.
Traction Control: As has been pointed out before, the problem in snow and low-traction driving environments is not getting going, it's stopping. TC does little to help this.
Note: I have all-wheel-drive on one of my vehicles.
Active suspension: Is the goal of the driving experience to drive a plushmobile, or is it to drive a vehicle that let's you have a bit of the road feel? This is a personal preference thing. I guess if your 70 and your bones ache at every jolt, then you will want this feature. Since it drives up the price, there should be plenty of each kind of vehicle available on the new and used markets for the forseeable future to satisfy everyone.

I imagine that's a pile of baloney. But, there are plenty of short people rightly upset about air bags, another safety improvement I guess you wholeheartedly endorse.

Pray tell where are these? Please show me -current- reliability statistics about repairs on any used car device that was introduced a decade ago.
The auto industry really doesen't give shit on a shingle about used cars, there are very few reliability studies on costs to repair them, but there's a whole lot of "heard it through grapevine" advice out there.
Once the vehcile has passed out of warranty period, the only people that care are the people selling extended warranties, and when the vehicle has passed out of extended warranty period (often 100K) then not even those people care.
Keep in mind that if a vehicle model has terrible long-term repair costs, the car companies want to suppress that so that it doesen't reduce the resale value of new cars (because a lot of new car buyers look at that data when choosing new cars) and if a vehicle model has phenominally great long term reliability the car companies also want to suppress that so that people who would otherwise dispose of perfectly good used cars and buy new ones to replace them, don't stop doing that.

The computer is far more reliable than any of the mechanicals that it is set to controlling.

When that happens there will be plenty of people selling ticket defeaters that reprogram the computer to not do this. Not to mention that there's no central database of VIN-to-drivers out there.
Keep in mind that for a car computer to know it's own license number means that when you put plates on a vehicle that your going to have to input the license plate number. If your car has a police-informing computer in it, you just stick in a bogus plate number like EATME and the computer can only tell the police that the car with plate number 'eatme' has violated the speed limit. Otherwise the computer only sends the VIN to the cops. That's fine if your state can match up the owner and VIN number for the police, but if the car is titled in another state? Suppose you decide to drive cross-country?

And an even more interesting thing would be how is the car computer going to know what speed zone your in to know you have violated the speed limit? What if your driving in a state that has a 100Mph speed limit? Montana used to have no daytime speed limit, as a matter of fact.

I believe in every state, car insurance companies are very heavily regulated by the states as to what they are permitted to rate. Here in Oregon for example the insurance companies are only allowed to go back 3 years. You could have committed vehicular homicide 4 years ago, drunk as a skunk, and if you keep your nose clean for 3 years then your insurance rates are the same as someone with a clean 20 year record. Insurance companies are also not allowed to rate by gender, even though their actuarial tables almost certainly show fewer accidents by women (fewer women get drunk as skunks then smash things up) I think if such technology ever was developed you would see a huge cry by constituients and the politicians would put the kibosh on such plans.
Keep in mind we already today have the technology to do this, but nobody is proposing it.

It is surprising how you are focusing only on the negatives here. I for one would be perfectly happy with an alcohol sensor in the vehicle's air system that when it detected high concentration of alcohol, shut down the car. Such a system would certainly never be a problem for me, but it might keep you alive one of these days.

That is not why most people "don't buy them" Most people don't buy them simply because most car models don't OFFER them.
This is a case where the car companies decided a long time ago that it was cheaper to have just ONE kind of transmission in the vehicle, and so they stopped offering stick shifts for most vehicles. Then when people didn't buy them, folks like you run around claiming that nobody must want them because nobody is buying them, thus we shouldn't bother making them. Circular logic.
I also suspect that the auto companies feel it's easier to meet CAFE when shifting decisions are taken away from the driver and given to the computer. People don't always decide to shift in the most fuel-efficient manner, y know.

I drove a manual for 10 years as a daily commuter vehicle and never had a problem. So did a lot of people. Your taking your own experiences with them and trying to apply that to every other driver. The funny thing is your post here seemed to start out chastising me for doing the same thing.
I guess when it's my positive experiences with something (manual transmissions) that is bullcrap, and when it's your positive experiences with something (automatic transmissions) that you know best and I should shut my hole?
Ted
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See below.
DAS
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You sure take offense where none is present, don't you?
Did you not read the entire message? I wasn't being negative about the new technologies; I was pointing out a great new technology (direct-shift gearboxes) and how it's only really made possible by giving the computer direct control over throttle and other parts of the vehicle. I brought up the other points only to illustrate potential pitfalls of letting the computer have so much control, lest anyone like you think I'm in favor of having computers take over the world.
Your comments on active suspension tell me you really have no clue what it is? It's not something to make the ride more comfy -- it's to make the car handle better. Look it up.
You think ABS is only good on ice? ABS helps on wet surfaces and other situations. It'll even help in a hard emergency stop on dry pavement since you can still get wheel lockup. It's not only for morons but also for everyone else who has to slam on the brakes due to a moron running a stop sign in front of them.
Traction control helps in dozens of situations. The weather might be warm and dry, but when applying power pulling out onto the road from a parking lot you might have one driven tire with good traction and the other driven tire on a sandy spot on the road. Or it may just be a little rainy. In lots of situations, traction control will get you going faster without a tire spinning. If a car has ABS then traction control is very cheap for the manufacturer to put on a car rather than than limited-slip differentials and other technologies. When you have to merge into dense traffic and you have a tire losing its grip, it's good to have anything you can get whether it's traction control or anything else.
There are plenty of statistics showing what areas on a particular make/model/year are problematic. Consumer Reports gathers such information but there are plenty of others.
What percentage of people would go reprogramming their car's computer to defeat features built in by the manufacturer, regardless of cause? You might, I might, but the vast majority of average people wouldn't. It's hardly risk-free, most people wouldn't know about or have access to computer-reprogrammers, and many of them and wouldn't try them anyway.
No matter what state you live in, police from any other state can identify who owns the VIN of your vehicle(s).
How am I applying my experiences regarding manual trannies to every other driver? Did you not read my comment "I love manual transmissions"? Yet manual transmissions are ordered at a dismally low percentage on many vehicles, so manufacturers often end up dropping them from a model line. Enough of them have to be ordered to make it worthwhile. Other options are also dropped from a model line for much the same reason, along with many other reasons, of course. The Mitsubishi Diamante was once a very high-tech vehicle, but Mitsubishi dropped features like the rear-wheel-steering feature in the later years because it was ordered in a very tiny percentage of vehicles. Chrysler dropped AWD from the minivans, in part because it gave them more room to implement their new Stow-n-Go, but also because it was ordered in only a fraction of the total orders.
- - - - -

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You said:

I said:

You said:

My comments about the fancier transmissions being more expensive to repair were NOT gloom and doom, and I resented you claiming that they were.
Increasing the complexity of anything makes it more expensive to repair, and more prone to break down. Your pushing a transmission here that adds 2 extra gears, plus the ability for the driver to "click off lightning-fast upshifts and downshifts with the F1-style paddles" and on top of it this is a VW product and their current quality control sucks.
And you are claiming increased repair bills are a gloom-and-doom scenario? Pahgh!
In any case, the other items were the gloom-and-doom scenarios you requested - but I didn't say I agreed completely with them. You wanted to know the cons to those technologies, you didn't indicate you wanted to debate them until your response here.

No, that was an example only. Of course, ABS works in other scenarios - if you define "works" as "the ABS computer triggers it" not "works" as "saves you from a collision"

Do you regularly slam on the brakes? I don't - usually though because I tend to carry a lot of stuff around on a regular basis, and I don't enjoy computer parts, my laptop, paperwork, and such all sliding off the seats into a jumbled mess on the floor. I have learned some good driving techniques that allows me to avoid getting into most of those situations, and the few times that I do slam on the brakes it is when I'm going under 5Mph. (and yes, the shit all slides off the seats onto the floor)
Take your stop sign example. Yes, most people just drive through uncontrolled intersections with the stops against the cross traffic, blithly oblivious to the world. I do not. If I'm approaching an intersection with a car coming at right angles to where we would hit the intersection at the same time, I always start slowing even when I don't have a stop sign and he does, until I see him slowing. Then I let up on the brake but don't take my foot off it until I'm through the intersection.
Or take another example of a major throughfare and someone pulling out into traffic unexpectedly. I don't have this problem happen to me because as soon as I get on the throughfare I move to the center lane. I don't tool down the street in the right lane, I only get into it when I'm ready to turn off the intersection.
If it's a street with a single lane both directions, if I see a car waiting to pull into traffic I take my foot off the gas and on to the brake and let my car start coasting, until I see that he's not moving.
Of course, there are blind intersection scenarios and other fringe scenarios you can cite that ABS might do some good. Not common, though.

Why is the goal to get going into the road super fast? Once more this is a very rare intersection. I can think of only 1 in the entire city here that is like this, and probably 1,000 cars a day use it, there is no sandy spots on it.

Most dense traffic situations the road your on is going to be densely traveled also, and any sand on it will have been long ago beaten off. This is a contrived situation that is not common. And once your in the dense road, you can gas it.

No, they would just go to the hole-in-the-wall places that today specialize in getting polluting vehicles to cheat the emissions inspection, and those places would swap in a complete new refurb computer, then give them their old one in case they ever sell the car.
People pay more than that for radar detectors.

And if the owner claims they were not driving the vehicle? What then? That is why the photo radar people take the drivers pictures, they can match them against the drivers license if there's a dispute.

You are claiming that manual transmissions "get a bit tedious" on passenger vehicles. Which is your personal preference, it is not a property of the manual transmission. You also claim that most people don't buy them because they require attention from the driver. Once again this is a personal preference thing - they might require too much attention from you.

Once again, this is deliberate by the manufacturer. They start out with a model line where you can go to the dealer and see both manual and automatic, and the manuals are a bit cheaper. Then they jack up the price of the manual and the automatic so they are the same. Then the next year they drop the manual and it's now an orderable option, and you have to wait to get your car with it. Then the next year they tack $1000 onto the price of this option so now purchasers have to wait, plus pay a premium. Then they drop the manual completely, claiming there's no demand for it.
Ted
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As an automatic fan (something I began to appreciate as I grew up...) I wish we did not have to pay vast premiums for automatic gearboxes in Euope.
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Dori A Schmetterling wrote:

What is a typical cost for an automatic in Europe? The premium here in the USA is typically $800-$1200. I prefer standard shift myself and find it nearly impossible to find them as few dealerships are willing to stock them. I don't think manuals account for even 10% of auto sales in the US these days.
Matt
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It depends on the car, but I'd say GBP 1000 - 1500 is not an overestimate. In my own case (2001) the auto gearbox was actually included in the base price, but then it's a brand whose buyers tend to prefer auto for many of the models (Mercedes). I bought mine in Germany, where manuals for Mercs are more popular, but in the UK the vast majority of Mercs are sold with auto.
I don't know what the overall percentages manual:auto in Britain or western Europe are, but auto accounts for much less than half.
I had the impression from some posts here that auto on the US is very cheap, so I am a bit surprised it is as much as USD 1200, but it is still a lot less than here.
DAS
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