How do automatics "learn"?

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Or more precisely, how do you "teach" them? I've read that if you disconnect the battery you can make 'em "forget" and it will start over again, and relearn.

I'm curious what one can do to basically make it shift when you want it to. Dawned on me recently to simply let off in high hopes of getting it to shift--which is fine, assuming it won't downshift when you step on the throttle again.

Would be nice if I could somehow pick a shift schedule. I still say it'd be nice to have a light that would indicate imminent downshift!
 
Originally Posted By: Olas
If you want to control your gearbox to shift when you want it to, buy a manual.

his manual is rusting/almost unrealible at close to 300k miles.
i guess that's why he is asking? since most of his current drives are automatic...
 
Two of my three vehicles are manuals. Only my truck is an automatic. Try finding a crew cab half-ton in a stick that isn't rotted away!

After two decades of driving only stickshifts this automatic sometimes flummoxes me. At this time of year it's not so bad; the cool air means it locks up the convertor quickly. But in summertime it seems rather quick to unlock for some reason.

I know the engine is capable of pulling down to 1,200rpm but darned if I can give it much more than a hint of throttle. I don't mind it rev'ing up to say 3k when getting on the highway, but I want to give heavy throttle, run up to say 3k, then have it shift--and then get back on it. Just like how I'd drive any other vehicle.
 
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To be blunt, I think your problem is that you are expecting an automatic to drive like a stick. They don't and expecting one to is setting yourself up for a letdown. About the best you could do is find one with a manumatic mode and use that all the time. But then you may as well have bought the stick.

I don't get what the concern is with revs and such? Let it do its thing - with all the computers in them these days it won't do something stupid and it will protect itself. Change the fluid every 30k or so and it will live a long life.

It does take some adjustment coming from a manual but realize that the automatic does its thing differently. Just like every manual driver drives differently, so will an automatic. Neither is "wong" or "right" as both will get long life out of the components.
 
But that's the thing: when I'm accelerating I don't mind it rev'ing up. It's a nice feature that it will automatically upshift for me. And downshift when slowing down. And if I floor it I guess it's nice that will go as low as possible and pour on the power.

But when I'm holding speed I expect it to... not shift. It would get so much better fuel economy if it'd just learn the styles in my driving. As it's supposedly programmed to do. When I'm driving lightly and getting upshifts at 2k, then I want it to load down to 1,200rpm on hills. If I'm on it I don't mind it downshifting so as to stay above 2k (but that is a rarity for me).

How hard can it be?

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I still don't see how it's supposed to last longer, not when it unlocks the convertor so frequently. I guess it's no harder to replace a TC than a clutch; I've yet to figure out how long I can make a clutch last, so I probably shouldn't compare the two (249k is the longest I've made it, and that clutch was only half-worn).
 
Originally Posted By: itguy08
To be blunt, I think your problem is that you are expecting an automatic to drive like a stick. They don't and expecting one to is setting yourself up for a letdown. About the best you could do is find one with a manumatic mode and use that all the time. But then you may as well have bought the stick.

I don't get what the concern is with revs and such? Let it do its thing - with all the computers in them these days it won't do something stupid and it will protect itself. Change the fluid every 30k or so and it will live a long life.

It does take some adjustment coming from a manual but realize that the automatic does its thing differently. Just like every manual driver drives differently, so will an automatic. Neither is "wong" or "right" as both will get long life out of the components.

This.

And even an automatic with a manual mode will still unlock the torque converter if it thinks you're asking for too much.

Best to just not worry about it and let it do what it's gonna do.
 
I am probably expecting too much. Funny how after years of effort an automatic still can't rival the brains in my left foot.
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I'm curious how they learn, and how one can "teach" it to do so.
 
I see reviews of the newest cars where they are programmed so much for efficiency that the transmission will hold top gear too long. The other thing a computer controlled auto will have is hill logic. No matter what you do when going up hill, it will downshift to keep the revs up.

It may take a trip to the dealer to clear what has been learned. You can also make sure you have the latest upgrades that way.
 
Review the Caddie link above. The newer automatics are "learning" in that they adjust shift timing to prevent slipping/sliding into a gear too much ( in a broad range of temps, I might add) or banging into gear and giving a harsh ride or breaking components. They are not learning in that it "learns" you think it's ok to lug it at times. Not that all your driving maneuvers from a manual are "wrong" but some are not as conducive to best fuel economy/emissions/engine loading, etc. as they have tested for. Plus this changes as they age ( think of disk brakes "self adjusting" every time you brake)...

I agree sometimes they seem to shift "stupidly" but newer ones are almost as "perfect" as can be with normal driving. Best to just "squeeze" the throttle like we were all taught in drivers' ed and use it like a potentiometer to get you to what speed you want. Point and shoot if you will...

IMHO - the only other better trans you'll find that shifts like you are used to is the dual clutch ones like in some VW's ... those babies shift like a video game controller ( and they really do ) !! About the only thing I am a big fan of of VW !

BurrWinder
 
I doubt if the trans if ever going to "learn" to keep the TC locked to lower rpm than it is right now. It is a bit surprising it doesn't keep in locked to the point of increased NVH like many cars these days.
If you plan on keeping it for a while, it might be worth getting a mileage "tune" done for it that includes the transmission? If this beast becomes your commuter, a few hundred bucks for a tuner might be worth it for the mileage alone.
 
Originally Posted By: supton

But when I'm holding speed I expect it to... not shift. It would get so much better fuel economy if it'd just learn the styles in my driving. As it's supposedly programmed to do. When I'm driving lightly and getting upshifts at 2k, then I want it to load down to 1,200rpm on hills. If I'm on it I don't mind it downshifting so as to stay above 2k (but that is a rarity for me).

How hard can it be?


Do you know for certain it would get much better fuel economy? Hook up a scan tool and watch the instant MPG #'s. I think you'll be surprised that it really makes little difference.

When I had my manual G35 sedan, I could watch the instant MPG on the nav screen. Didn't matter much if I nailed it in 6th or dropped it to 5 and went 1/2 throttle or whatever. It was about the same. Yes there would be less pumping losses at WOT but you're not at WOT much.

You also have to remember it has no eyes. It can't see that you're loafing around going up hill with no cars in sight. Versus trying to pass someone at 1/2-3/4 throttle where you'd want that downshift. It can't see the traffic so it has to make some assumptions about what you want to do based on input.

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I still don't see how it's supposed to last longer, not when it unlocks the convertor so frequently. I guess it's no harder to replace a TC than a clutch; I've yet to figure out how long I can make a clutch last, so I probably shouldn't compare the two (249k is the longest I've made it, and that clutch was only half-worn).


Locking and unlocking the converter is no big deal - the converter is basically a fluid coupling and while they do wear out and break it's not the same thing as a clutch release. If you have one, watch the trans temp gauge - it really doesn't move in normal driving, only prolonged unlocked driving (like up a hill towing) will make it really go up.

Heat does kill them and it's why 30k or 60k flushes are so important, IMHO. We've got 149k on the "junk" CD4E in the wife's Escape just by doing normal changes.

In the end, they are 2 different animals and expecting one to behave like the other is just asking for frustration.
 
Typical case of heavy truck / little engine from a few years back. They're much better at this today, but they often have 3 more gears to work with, too.

My '08 4.7L Ram does the same thing though maybe not as early- trust me, driveability is BETTER if it unlocks to give the engine some help on gentle climbs rather than lugging the engine. Also, most torque-convertor lockup clutches aren't built to actually hold against a lot of torque, though there are exceptions like big Allisons. Typical passcar/light duty truck lockup clutches do their job in steady-state cruising, and let the fluid coupling handle the heavy loads of acceleration and hill-climbing Part of the reason the TC clutch releases early is self-protection.
 
Originally Posted By: BurrWinder

IMHO - the only other better trans you'll find that shifts like you are used to is the dual clutch ones like in some VW's ... those babies shift like a video game controller ( and they really do ) !! About the only thing I am a big fan of of VW !

BurrWinder


I don't know... I had a rental VW with a DDC automatic a couple of weeks ago, and it certainly had its strong points: not downshifting too early or upshifting too late and a general feel of ample torque at almost any given moment. But it did some really crazy stuff, too- particularly the lurch after you roll 10 feet from a dead start, harsh shifts all around, and the odd feel of the clutch starting to engage as soon as you lift your foot off the brake. If I'm going to have an honest-to-god *clutch* instead of a torque convertor, I think I want the pedal to go with it instead of the computer trying to get it right.
 
Originally Posted By: itguy08
Originally Posted By: supton

But when I'm holding speed I expect it to... not shift. It would get so much better fuel economy if it'd just learn the styles in my driving. As it's supposedly programmed to do. When I'm driving lightly and getting upshifts at 2k, then I want it to load down to 1,200rpm on hills. If I'm on it I don't mind it downshifting so as to stay above 2k (but that is a rarity for me).

How hard can it be?


Do you know for certain it would get much better fuel economy? Hook up a scan tool and watch the instant MPG #'s. I think you'll be surprised that it really makes little difference.


I have hooked up my Scanguage, and it does eek out like 2mpg better if I force a downshift into 5th rather than let it stay in 6th unlocked. Going from like 10-11 to 12-14. RPM might drop or be about the same; but getting rid of convertor loss is the big issue.

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You also have to remember it has no eyes. It can't see that you're loafing around going up hill with no cars in sight. Versus trying to pass someone at 1/2-3/4 throttle where you'd want that downshift. It can't see the traffic so it has to make some assumptions about what you want to do based on input.


I get that; but what is this adaptive stuff about then?

I'm just trying to figure out how to make it respond the way I want it to. I'm slowly getting there, learning how much throttle I can press down before it will shift.

Originally Posted By: itguy08
Originally Posted By: supton
I still don't see how it's supposed to last longer, not when it unlocks the convertor so frequently. I guess it's no harder to replace a TC than a clutch; I've yet to figure out how long I can make a clutch last, so I probably shouldn't compare the two (249k is the longest I've made it, and that clutch was only half-worn).


Locking and unlocking the converter is no big deal - the converter is basically a fluid coupling and while they do wear out and break it's not the same thing as a clutch release. If you have one, watch the trans temp gauge - it really doesn't move in normal driving, only prolonged unlocked driving (like up a hill towing) will make it really go up.

Heat does kill them and it's why 30k or 60k flushes are so important, IMHO. We've got 149k on the "junk" CD4E in the wife's Escape just by doing normal changes.


I get that; I don't see elevated trans temps unless if it runs unlocked. And I know this trans is "fine" with high temps. No worries there. Then again what I've seen indicates that it uses variable lockup, which is the same thing as "slipping the clutch". To me anyhow. Perhaps they use it only for reducing shift shock, I dunno. Oh: the service for this trans says to "check" the fluid, and when it gets loaded up with material, then change. I have read of at least one case of the TC wearing out of clutch material on these trucks (155kmiles IIRC).

I have no problem running a vehicle past 200k--but it'd be sad if my VW shows better longevity than a Toyota, IMO. When I bought this truck I was only planning on driving to 150-180k, then trading. Now I'm not so sure, and might try to run as long as possible.

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In the end, they are 2 different animals and expecting one to behave like the other is just asking for frustration.


I get that; I'm just seeing if there is anything else I can do to "enjoy" the experience. It's not bad at the moment, I've adjusted. For the most part. If I can do something a bit different and be "more happy" then that might be nice too.
 
Originally Posted By: 440Magnum
Typical case of heavy truck / little engine from a few years back. They're much better at this today, but they often have 3 more gears to work with, too.

My '08 4.7L Ram does the same thing though maybe not as early- trust me, driveability is BETTER if it unlocks to give the engine some help on gentle climbs rather than lugging the engine. Also, most torque-convertor lockup clutches aren't built to actually hold against a lot of torque, though there are exceptions like big Allisons. Typical passcar/light duty truck lockup clutches do their job in steady-state cruising, and let the fluid coupling handle the heavy loads of acceleration and hill-climbing Part of the reason the TC clutch releases early is self-protection.



That is an interesting thought, that the clutch cannot handle high torque (good thing my engine doesn't make much!).
 
I get that; I'm just seeing if there is anything else I can do to "enjoy" the experience. It's not bad at the moment, I've adjusted. For the most part. If I can do something a bit different and be "more happy" then that might be nice too.[/quote] Supton (Sorry my multi quote skills stink!)

The other kind of "learning" you are describing is just as you are doing, trying to "keep" it in higher gear longer - or getting a quicker downshift at let's say 35-40ish or highway kickdown downshift... these are what are learned. Obviously only so much "wiggle room" in there for a given application. More like teaching it you drive like a grandma and don't like any too firm upshifts or downshifts, or the opposite - driving it like you stole it and like the shifts to be "hair trigger" both in downshifts and firm/harsh upshifts.

BurrWinder
 
In pretty much in all modern automatics, there is a portion of the code that remembers user's throttle input. That information is then used to alter the default shift points. That's how modern automatics learn.

I'm guessing this information is stored in the temporary memory, sort of like RAM, and it gets erased when the power is lost (battery disconnected). That's when the TCM reverts to the default shift settings.
 
Originally Posted By: supton

I get that; but what is this adaptive stuff about then?


The linked article a while back was pretty good. From what I gather with a conversation with a Ford tech was that the transmission learns how to shift better. It learns the various line pressures and has accelerometers that it uses to get the smoothest shift. As these things age they may need more or less line pressure to get a good and timely shift. It constantly learns that. Similar to how a modern fuel injected car "learns" the fuel trim for that particular car.

It may "learn" your input over time or if you like to use lots of throttle, etc but I don't think they learn more than your basic driving habits. It's still going to do what it's programmed to do but the adaptive learning tailors it more to your driving situation.

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I'm just trying to figure out how to make it respond the way I want it to. I'm slowly getting there, learning how much throttle I can press down before it will shift.


Maybe a tuner or a vehicle with a manual override. Although most of the manual overrides will still stop you from doing crazy things.

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Oh: the service for this trans says to "check" the fluid, and when it gets loaded up with material, then change. I have read of at least one case of the TC wearing out of clutch material on these trucks (155kmiles IIRC).


IMHO that's some Bravo Sierra right there. Ford is the same way with the transmissions in my vehicles. I still let the dealer do a flush every 30k. Would rather spend the $200 than risk a transmission rebuild. It seems like the better option no matter the manufacturer's "recommendation".

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I get that; I'm just seeing if there is anything else I can do to "enjoy" the experience. It's not bad at the moment, I've adjusted. For the most part. If I can do something a bit different and be "more happy" then that might be nice too.

Maybe just let it do it's thing?
smile.gif
 
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