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monchito18
04-07-2009, 03:10 PM
Hello people, I was wondering if using the AT transmission in manual alot shifting from low to 2nd and 3rd and drive eventually does it damage the transmission?
I know its not a bad thing to do but in a daily use like that does it make any damage?

supmet
04-07-2009, 03:16 PM
Gear limiting properly won't hurt it. Forcing hard downshifts and redlining because you aren't limiting properly will blow your tranny eventually.

LtNoogie
04-07-2009, 03:21 PM
I do that alot too. I find that the AT shifts to 3 too early sometimes and then the engine lugs when I try to accelerate. I frequently "manually" shift from 2 to 3.

Also when in D, the transmission does not downshift to 2 and the engine lugs when coming out of a turn at the light.

monchito18
04-07-2009, 03:25 PM
Manual says 3->2 53mph and 2->L 26mph thats on page 111 of my 2009 yaris.

MadMax
04-07-2009, 03:32 PM
That seems high, I will pop my AT into 3 to kick in the DCFO when slowing but I won't pop it into 2 until it is at least below 30 MPH (more like 20 MPH). I would never kick it into L at 26 MPH!

But I do "shift" my auto all the time, mostly downshifting. It won't hurt it as long as you aren't doing anything dumb (such as trying to kick it into 2 at 75 MPH). I do like the way the AT shifter is gated, it allows more options when driving the Yaris...

Cheers! M2

LtNoogie
04-07-2009, 03:34 PM
Yeah, I don't downshift so much. I mostly upshift from 2 -> 3 at around 3000 rpm and 3 -> D at the same RPM. Mostly, I shift based on the way the engine sounds and the way the car feels.

Lafiro
04-07-2009, 03:55 PM
Is it even ok to be doing this to the car????

I mean I do this all the time, changing it from D to 3, just to get the car to slowdown/be able to accelerate when needed...

Is it causing damage?

IllusionX
04-07-2009, 04:19 PM
I don't think you should be shifting gears very often with your AT transmission. At least, not all the way to 1st.

if you have a tiptronic transmission.. hell yeah, play with it.
http://flickr.com/photos/joshphotographic/3268318500/

monchito18
04-07-2009, 04:25 PM
I only use 1st to start from 0 mph but from then I never go to 1 unless I stop completely back to 0 so normaly I just shift to 2nd even if im at 5mph. I think its ok

jdinrc
04-07-2009, 06:54 PM
No, it doesn't harm the tranny. It still works the same internally, but you are deciding when to shift instead of letting it do that for you. Like the other said, you would get damage if you forgot to shift for long periods and worked the engine/tranny too hard, or if you downshift at too high revs.

Maxh91
04-07-2009, 09:12 PM
Manual says 3->2 53mph and 2->L 26mph thats on page 111 of my 2009 yaris.

It is also Ok to use as Engine braking?
(Not high RPM.)

monchito18
04-07-2009, 11:02 PM
It is also Ok to use as Engine braking?
(Not high RPM.)

I don't know but I dont think it's good.
I don't know much of AT transmissions.

Lafiro
04-08-2009, 10:59 AM
I notice on a downhill, happens every day I go to work, I touch the brake even a bit, and the engine downshifts all by itself causing engine braking/3k rpm or so..

I know the car senses it needs help stopping so it downshifts, but also cuts the fuel usage to save gas.

IllusionX
04-08-2009, 02:10 PM
there's no such thing as engine braking (see jacob) on our cars.

Lafiro
04-08-2009, 02:37 PM
there's no such thing as engine breaking (see jacob) on our cars.

So then explain to me what my car is doing then..... because it sure does sound like engine braking all being done when it notices the brakes arent slowing the car down as muhc as they should(going down a downhill)

MadMax
04-08-2009, 03:41 PM
there's no such thing as engine breaking (see jacob) on our cars.

WTF? :iono:

DFCO is initiated by engine braking, so if it doesn't exist, how does DFCO work?

Or, are you simply pointing out the difference between "braking" and "breaking?" If that is the case, then there is such a thing as "engine breaking," but it isn't what we are talking about here!

Cheers! M2

supmet
04-08-2009, 03:44 PM
there's no such thing as engine breaking (see jacob) on our cars.

So then explain to me what my car is doing then..... because it sure does sound like engine braking all being done when it notices the brakes arent slowing the car down as muhc as they should(going down a downhill)

He's saying we don't have jake brakes, which is true because we don't drive semi trucks. I guess he doesn't realize that using downshifting to slow down is also called engine braking??

As for engine braking being good for an auto, the car does it automatically as someone already said. As long as your not forcing hard downshifts, it isn't that bad. I do it all the time because I live around a ton of hills. I usually keep it limited at3 until I'm on a freeway onramp...(I know its bad for mpg, but its worse for my brakes not too). Also if you have to slow down and speed up a lot going up or down a hill, it will cause less wear on your transmission to keep it locked in 2 or 3, then to be shifting between them every couple seconds.

IllusionX
04-08-2009, 03:45 PM
dunno, it never occurred to me to actually call it engine braking ?!?

i also just noticed i made a typo on "braking". I corrected it on my post above.

Forrest
04-08-2009, 04:47 PM
If you wanted to shift all the time, why didn't you buy a standard??? instead of an AT?

LtNoogie
04-08-2009, 04:50 PM
Sometimes, decisions are made to accomodate significant others who may also drive the car. That doesn't mean we can't find ways to extract the maximum enjoyment we can from driving it.

KCALB SIRAY
04-08-2009, 05:00 PM
Sometimes, decions are made to accomodate significant others who may also drive the car. That doen't mean we can't find ways to extract the maximum enjoyment we can from driving it.

hear hear!

MadMax
04-08-2009, 05:44 PM
Sometimes, decions are made to accomodate significant others who may also drive the car. That doen't mean we can't find ways to extract the maximum enjoyment we can from driving it.

Exactly, plus you can always shift an automatic transmission all you want, but you can't never make a standard transmission shift itself! :thumbsup:

Cheers! M2

Forrest
04-08-2009, 06:42 PM
Exactly, plus you can always shift an automatic transmission all you want, but you can't never make a standard transmission shift itself! :thumbsup:

Cheers! M2

:thumbup::thumbup::thumbup: Well said !

wsladaritz
04-08-2009, 06:52 PM
okay... so with all this shiftin talk on AT I've got another question. What about shiftin from D to N when ur coasting down a big hill?

MadMax
04-08-2009, 07:18 PM
okay... so with all this shiftin talk on AT I've got another question. What about shiftin from D to N when ur coasting down a big hill?

The consensus was it was better to leave it in gear and have the DFCO stop all fuel from going to the cylinders then to let it idle in N and have some (albeit very little) fuel still injecting...

It may be a small difference, but it does add up!

Cheers! M2

wsladaritz
04-08-2009, 07:20 PM
cool, next quesiton...

what does DFCO stand for? lol

supmet
04-08-2009, 08:48 PM
cool, next quesiton...

what does DFCO stand for? lol

http://www.yarisworld.com/forums/showthread.php?t=4248

MadMax
04-08-2009, 11:20 PM
cool, next quesiton...

what does DFCO stand for? lol

Deceleration Fuel Cut-Off...simply put it shuts down fuel injection during engine braking...if you put the car in neutral, there is no engine braking!

Oh, and I forgot to mention this earlier; but in many states it is actually technically illegal to put your car in neutral while driving. Yes, I didn't believe it either, but this is the law in Texas...

Sec. 545.406. COASTING. (a) An operator moving on a downgrade may not coast with the gears or transmission of the vehicle in neutral (Source (http://www.statutes.legis.state.tx.us/DocViewer.aspx?K2DocKey=odbc%3a%2f%2fSOTW%2fASUPUB LIC.dbo.vwSOTW%2fTN%2fS%2fTN.545%40SOTW&QueryText=545.406&HighlightType=1))

Cheers! M2

ruimond
04-08-2009, 11:54 PM
okay... so with all this shiftin talk on AT I've got another question. What about shiftin from D to N when ur coasting down a big hill?

I heard shifting to different gears when moving in an AT is bad for the transmission. Not 100% on this though.