Auto Gear

[thou1584]

Guys I have a small problem!!! I did a recent auto trans oil change, but the mechanic had overfilled more than the required level, now the gear changing has become a little late, especially from gear 2 to gear 3. My question is if i reduce the oil back to the normal level will the gear shifting become alright as before?

please highlight me on this !!!

[chan5]

Guys I have a small problem!!! I did a recent auto trans oil change, but the mechanic had overfilled more than the required level, now the gear changing has become a little late, especially from gear 2 to gear 3. My question is if i reduce the oil back to the normal level will the gear shifting become alright as before?

please highlight me on this !!!

my gearbox also overfilled by a service station and car is toyota diesel wagon.

Can someone explain what those two bands in oil level rod says hot and cold . What's the level it should be correct position.

I knew the level should be between 2 cold margins in early morning start.but various mechanics say various BS.

Please shed some light , and gearbox is working fine except very rarely (once a week) it takes about 2 seconds to engage D from P.

Does it cause due to this incorrect oil level.

[Scooter]

Hi Mag, interesting thread. What happens inside the torque convertor at vehicle stopped/engine on idle is complex. You might enjoy this Toyota training manual chapter on torque convertors and what goes on inside that big metal donut:

http://www.autoshop101.com/forms/AT02.pdf

If the AT02 number stuff in the address is played with (e.g. AT03, AT04.....) you can get all the Auto Transmission training stuff.

Did I notice someone editing your posts on another AL thread last night? Oh, the hokey-pokey! :-)

[Magnum357]

thou1584,

From what I gather overfilling can result in permenant damage on some transmissions, not all. Slipping, overheating, aerating, etc etc are some of the symptoms of overfill. Draining to the correct level is the immidiate action and hope that things get back to normal, if not .......hope for the best!

chan5,

The cold level is the oil level when you typically check the level in the morning before any running has been done.

Hot level is when the car has been doing some running and the level is checked. So having the level between cold and hot is not the ideal level as if you check the level early morning and find it between hot and cold and then do some running and check the level when the oil is hot you may actually see that you have too much oil with the expansion.

Similarly if you do some running and check the level and find it between hot and cold you may be actually running with a low oil level, which you will be able to confirm when you check early morning when the oil is cold before any running.

So if yoiu check the level in the morning the ideal level should be at the cold level, if you check the level after running the level should and would be at the appropriate hot level.

Scooter,

Thanks for that.

Yeah even I saw that 2 of my posts on another thread in reply to some others notorious for abuse, had been taken off. That seems to be the way "things" are done on autolanka. It seems notorious abusers have their way in Srilanka and Autolanka!

Edited September 15, 2012 by Magnum357

[Supra_Natural]

Scooter,

Thanks for that.

Yeah even I saw that 2 of my posts on another thread in reply to some others notorious for abuse, had been taken off. That seems to be the way "things" are done on autolanka. It seems notorious abusers have their way in Srilanka and Autolanka!

Hey, if you don't like it man, please feel free to go on your way....

[Pericles]

Yeah even I saw that 2 of my posts on another thread in reply to some others notorious for abuse, had been taken off. That seems to be the way "things" are done on autolanka. It seems notorious abusers have their way in Srilanka and Autolanka!

I'm gonna tell you this once. You have a problem, you report it.

Considering your attitude, I find it quite likely you bought whatever abuse came your way, on yourself. And if you choose this snide attitude about how things are done, you'll find I don't have a lot of patience about things like that.

[kit]

i also had the same issue. (1999- Butterfly model)

replaced some components at Gear Box.

costs 50,000.00

now this is OK

[Magnum357]

Hey, if you don't like it man, please feel free to go on your way....

Thanks for the advice but I am not ruffled by blame, praise or slander so I don't think I need go!

[Magnum357]

I'm gonna tell you this once. You have a problem, you report it.

Considering your attitude, I find it quite likely you bought whatever abuse came your way, on yourself. And if you choose this snide attitude about how things are done, you'll find I don't have a lot of patience about things like that.

Did it seem I had a problem ? BUT some others did definitely have a BIG problem with my post going by their abusive posts in reponse, their problem is not my problem . Does reporting problems to the authorities in Srilanka (autolanka???) get any favorable results????

I don't "buy" any abuse posted to me, neither do I return it by return post, I simply treat it as garbage and give it its due place!

If you reckon I have a "snide attitude" wonder what you have to say about the attitude of those "know all" notorious abusers who seemingly rule the roost on autolanka by habitually abusing any member in raw filth at the drop of a hat and still get away having their way?????

It does not bother me. I am here to learn from other members and sharenotes with others on things related to vehicles.

This is Srilanka where "might is right". If its decided to ban me from autolanka for expressing my views with civility, well then it proves my point that notorious abusers have their way even on autolanka.

Have a nice day!!

Edited September 17, 2012 by Magnum357

[harshansenadhir]

My posting contained independant advise which I received from two professionals who are amply qualified mechanical engineers and are heading the workshops of two of the countries automobile dealerships. (Hyundai Lanka and LOLC Motors.)

The fact of the "clutch slipping" I mentioned was with reference to a manual transmission. Where on an incline the gear can be engaged and with the clutch engaged halfway the vehicle can be stopped from rolling backwards without the use of the brakes. When this is done the clutch plate wears out faster I was told. Similarly in an automatic when the brake is pressed in "D" the forward momentum is stopped by the wheels braking and not by the transmission disengaging, the momentum of the transmission is stopped with the resistance from the wheels. I was told when this happens the strain is on what is called the " wet-plate clutch packs" within the automatic transmission box and with time gears not engaging, gears slipping etc etc are the problems than can arise in an automatic transmission. This is not what I am saying but independantly verified by these two engineers.

Though you authoritatively informed with much pomp and glory that there is no clutch in an automatic transmission there is a clutch. They are called wet-plate clutches. Here are the components of an automatic transmission

The planetary gearset

The set of bands to lock parts of a gearset

The set of three wet-plate clutches to lock other parts of the gearset

The hydraulic system that controls the clutches and bands

The large gear pump to move transmission fluid around

So "Pundit Professor" there is something called a clutch in an automatic transmission.

I do not know what competency you have in the field of automobile engineering and whether you are more qualified and have more experience than these two individuals BUT this is the advice I received and I was just passing on that information for the benefit of the members.

There are two sides of the story of keeping an Automatic in D on red lights. Yes, you're correct on the "clutch plates" which are inside the gearbox. However, when you're on a standstil, the torque converter does not transfer any power towards the gearbox (if your engine speed is in the manufacturer recommended idle speed that is). It only would transfer the maximum engine speed / torque to the gearbox once it completes the coupling. Therefore, keeping in D and stopping on a red light does not cause any unusual wear 'n tare in this clutch plate set.

on the other hand, when you frequently shift between N and D, the piston which operates the 1st gear (also the reverse gear) operates back and forth everytime you change from N to D. This can cause an unusual wear 'n tare on the piston (1st and reverse it's the same), Valve body and the valve which operates that piston and also the main shaft inside the gearbox.

The pros of shifting into N in a red light the less load on the engine and mounts mainly. The cons would be the unusual ware of the pistons and associated moving parts in the gearbox and valve body.

What I personally do is if it's stop 'n go traffic and even if the lights are at the verge of changing say 30 seconds, I stay on the D. If I apporached the light while it's turning into amber / red, then change to N and wait.

[Supra_Natural]

Did it seem I had a problem ? BUT some others did definitely have a BIG problem with my post going by their abusive posts in reponse, their problem is not my problem . Does reporting problems to the authorities in Srilanka (autolanka???) get any favorable results????

I don't "buy" any abuse posted to me, neither do I return it by return post, I simply treat it as garbage and give it its due place!

If you reckon I have a "snide attitude" wonder what you have to say about the attitude of those "know all" notorious abusers who seemingly rule the roost on autolanka by habitually abusing any member in raw filth at the drop of a hat and still get away having their way?????

It does not bother me. I am here to learn from other members and sharenotes with others on things related to vehicles.

This is Srilanka where "might is right". If its decided to ban me from autolanka for expressing my views with civility, well then it proves my point that notorious abusers have their way even on autolanka.

Have a nice day!!

Yes, it does seem like you have a problem, hence the warning. In addition, I think you've already realized that people on this forum generally have a big issue with people providing incorrect information, which you sort of did.

If that was how Autolanka operated old boy, you'd have not been able to even put up this rant.. But mind you, patience is not limitless, so maybe you should tone it down a little all right? Especially since the information you provided was not as correct as you seemed to think it was....

Edited September 17, 2012 by Supra_Natural

[ajwad]

i also had the same issue. (1999- Butterfly model)

replaced some components at Gear Box.

costs 50,000.00

now this is OK

Hi,

Did you do a repair??? where did you do it??? and how long have you been using the car now???

[Pericles]

Did it seem I had a problem ?

Correct in 1!

Does reporting problems to the authorities in Srilanka (autolanka???) get any favorable results????

Try it and find out, instead of trying to be an ass. Something with you are succeeding at quite marvelously, I might add.

[chan5]

If I apporached the light while it's turning into amber / red, then change to N and wait.

May i ask what's the rationale behind this habit ?

[harshansenadhir]

May i ask what's the rationale behind this habit ?

Waiting time. Usually a red light take around minute or more to turn back into green. Why stressing the entire drivetrain for that long?

[Magnum357]

There are two sides of the story of keeping an Automatic in D on red lights. Yes, you're correct on the "clutch plates" which are inside the gearbox. However, when you're on a standstil, the torque converter does not transfer any power towards the gearbox (if your engine speed is in the manufacturer recommended idle speed that is). It only would transfer the maximum engine speed / torque to the gearbox once it completes the coupling. Therefore, keeping in D and stopping on a red light does not cause any unusual wear 'n tare in this clutch plate set.

on the other hand, when you frequently shift between N and D, the piston which operates the 1st gear (also the reverse gear) operates back and forth everytime you change from N to D. This can cause an unusual wear 'n tare on the piston (1st and reverse it's the same), Valve body and the valve which operates that piston and also the main shaft inside the gearbox.

The pros of shifting into N in a red light the less load on the engine and mounts mainly. The cons would be the unusual ware of the pistons and associated moving parts in the gearbox and valve body.

What I personally do is if it's stop 'n go traffic and even if the lights are at the verge of changing say 30 seconds, I stay on the D. If I apporached the light while it's turning into amber / red, then change to N and wait.

Thanks for that info. In fact what I too mentioned was it is more advisable shifting into "N" for long stops in traffic rather than the stop'n go as you too have mentioned.

However even at the manufacturer recommended idling speed which usually is within the ranges of 750-950rpm on most vehicles, when in "D" without any accelarating the vehicle crawls forward and it is primarily to stop this forward crawl that the brakes have to be used. So therefore it is not the case the vehicle does not move at all in "D" when idling. Doesn't this suggest that there is power being transmitted to the transmission even when standing idling on "D"? To clarify further I give the following link

http://auto.howstuff...ansmission4.htm

In the illustration moving the shift lever to the various positions (PRND321) depicts how the power is transmitted in the various positions and the only positions where power is not transmitted are P and N as you would see.

Having said that it would be interesting to see which type of repair costs more with reference to the piston, valves and main shaft (moving from D to N often) and a repair involving the clutch packs etc etc related to using the brake while idling on "D", and what type of problem is commonly seen in automatic transmissions.

Edited September 17, 2012 by Magnum357

[Magnum357]

Yes, it does seem like you have a problem, hence the warning. In addition, I think you've already realized that people on this forum generally have a big issue with people providing incorrect information, which you sort of did.

If that was how Autolanka operated old boy, you'd have not been able to even put up this rant.. But mind you, patience is not limitless, so maybe you should tone it down a little all right? Especially since the information you provided was not as correct as you seemed to think it was....

What was the "problem" which you see as my "problem"? Wrong information is it? As for the information I gave it was not my own but professional advise which I too received from two qualified mechanical engineers heading two workshops at two car agencies in the country. That addvice I do not doubt anyway.

As you assert if members have a problem with wrong information being posted I wonder what you and the other "members" have to say with the very wrong info posted by "The Stig" who quite authoritatively professes that there is no clutch in an automatic transmission when it is manifestly clear that there is a clutch mechanism even on an automatic transmission.

Well if you are "warning" me for posting allegedly "wrong" information which incidentally was professional advice, I would appreciate if the same yard-stick is used to "warn" the others who state (unprofessionally??) that there is no clutch in an automatic transmission unless of course you conclude that type of "wrong" info from members such as "The Stig" are condoned by the membership !!!

Edited September 17, 2012 by Magnum357

[Pericles]

Well if you are "warning" me for posting allegedly "wrong" information which incidentally was professional advice, I would appreciate if the same yard-stick is used to "warn" the others who state (unprofessionally??) that there is no clutch in an automatic transmission unless of course you conclude that type of "wrong" info from members such as "The Stig" are condoned by the membership !!!

If you have a problem with the Stig's post, report it, instead of your snide commentary, which frankly, is quite unentertaining.

[harshansenadhir]

Thanks for that info. In fact what I too mentioned was it is more advisable shifting into "N" for long stops in traffic rather than the stop'n go as you too have mentioned.

However even at the manufacturer recommended idling speed which usually is within the ranges of 750-950rpm on most vehicles, when in "D" without any accelarating the vehicle crawls forward and it is primarily to stop this forward crawl that the brakes have to be used. So therefore it is not the case the vehicle does not move at all in "D" when idling. Doesn't this suggest that there is power being transmitted to the transmission even when standing idling on "D"? To clarify further I give the following link

http://auto.howstuff...ansmission4.htm

illustration moving the shift lever to the various positions (PRND321) depicts how the power is transmitted in the various positions and the only positions where power is not transmitted are P and N as you would see.

What torque converter transfers in idle is a fraction of torque what it can transfer in higher RPMs and when coupling is done as I said. You would understand this, if you jack up one of drive wheels in a manual car keeping the gear in neutral position. Still wheel would spin. That doesn't mean proper torque / power transferring to the wheels in the neutral position.

Also, torque converter does not operate in different modes depending on the position of the shift lever. Which means, there's no "disengage" of the torque converter takes place when you transfer from D to N as that diagram suggested. Amount of power / torque transmitted by the torque converter is only determined by the

1. Engine speed (speed of the primary turbine inside the torque converter)

2. Hydraulic pressure (created by the oil pump inside the gearbox)

since both are very low at idling what it tranmits can be negligeble.

Seems you're into more of online content than practical, let me quote following from http://auto.howstuff...r.htm/printable

If the engine is turning slowly, such as when the car is idling at a stoplight, the amount of torque passed through the torque converter is very small, so keeping the car still requires only a light pressure on the brake pedal.

The part in question is the friction plates set (clutch plates as you mentioned) that does completely a different role than the clutch mechanism of a manual gear car. In simple terms, it enables a smooth engaging of gears during shifts. These plates are many in numbers (the AL4 gearbox which we repaired about a month back had 21 of these).

When the gear in D (1st piston presses the clutch plate set and ready to turn the out put shaft) and brakes are applied (out put shaft cannot turn) rather than slipping all these plates, the gearbox input shaft will stop rotating. (this will be allowed within the torque converter in idle speed) If you release the brakes, the output shaft can turn allowing the input shaft (turned by the secondary turbine of the torque converter) using the minimal torque available.

So in a nut shell, the power engage / disengage from engine to gearbox in an auto tranny is done by the torque converter. There won't be any slipping of clutches sort of happens (like in clutch balancing on an uphill of a manual tranny) if you shift to D and hold onto brakes.

argument sake, let's say the said friction plates (clutch plates) of an auto tranny are subjected to unusual ware 'n tare when in D or any drivable gear position with the brakes applied. If torque converter transmits ample power to let these plates slip and go to a complete mockery, vehicle manufacturers would certainly come up with a mechanism of releasing the piston until the brakes are released, like the auto clutch system you find in Citroen DS. Why there's no such worry is the torque converter does its job of clutch mechanism of a manual tranny.

Having said that it would be interesting to see which type of repair costs more with reference to the piston, valves and main shaft (moving from D to N often) and a repair involving the clutch packs etc etc related to using the brake while idling on "D", and what type of problem is commonly seen in automatic transmissions.

For your information, the wear and tear of the pistons and main shaft is irreversible. During the repair of the very same AL4 gearbox I've mentioned, we had to change all 7 pistons and a main shaft as main shaft was worn out to a level where it leaks oil between the shaft and the rubber seal of the piston. The same set of friction plates could've re-used as whatever the wear 'n tare of the entire set has been divided among 21 plates. But still for all we replaced with brand new set but initial test drives were done with the old set of plates. Set of friction plates can be brought brand new but the main shaft is not an item which is available as a replacement part.

So in conclusion, the lesson I learnt is wear 'n tare of the piston and main shaft is costly affair than friction plates.

[Magnum357]

Harshansenadhir,

Thanks a bunch for that very informative explanation.

[Magnum357]

If you have a problem with the Stig's post, report it, instead of your snide commentary, which frankly, is quite unentertaining.

When rules regulations and laws are abused before the very eyes of the Sri Lanka police they too insist that some one first make a complaint for them to act!

I am not here to "report" anyone, rather I am here to share and compare notes and learn about motor vehicles which is the hobby of many of us here. If I am not mistaken one of the responsibilities of moderators on internet forums is to monitor abusive posts, and at that abusive posts using raw filth, and act appropriately, unless of course AL is an exception.

I was purpotedly "warned" by Supra-Natural not by anyone reporting me isn't it? So if I deserve a "warning" without anyone reporting me, how is it that I have to report someone to see any action? Unless of course "monitored action" for such abusive posts using raw filth is not warranted on AL as those posts are considered as "entertaining"!

Edited September 19, 2012 by Magnum357

[Supra_Natural]

When rules regulations and laws are abused before the very eyes of the Sri Lanka police they too insist that some one first make a complaint for them to act!

I am not here to "report" anyone, rather I am here to share and compare notes and learn about motor vehicles which is the hobby of many of us here. If I am not mistaken one of the responsibilities of moderators on internet forums is to monitor abusive posts, and at that abusive posts using raw filth, and act appropriately, unless of course AL is an exception.

I was purpotedly "warned" by Supra-Natural not by anyone reporting me isn't it? So if I deserve a "warning" without anyone reporting me, how is it that I have to report someone to see any action? Unless of course "monitored action" for such abusive posts using raw filth is not warranted on AL as those posts are considered as "entertaining"!

You were told to tone it down because you were casting aspersions on the way AL "Works". Now you appear to be telling the Moderators how to do their jobs... Dear me you really are one of those "what does this button do" types aren't you?

The information you posted was incorrect, this was pointed out to you, where was "raw filth" used may I ask?

[Magnum357]

You were told to tone it down because you were casting aspersions on the way AL "Works". Now you appear to be telling the Moderators how to do their jobs... Dear me you really are one of those "what does this button do" types aren't you?

The information you posted was incorrect, this was pointed out to you, where was "raw filth" used may I ask?

I have not said anywhere as to how the moderators on AL should do their jobs as that is not my job! What I have said is how moderators on other forums do their jobs and that I feel that AL is an exception. You seem to have got the wrong end of the stick!

So the post saying there is "no clutch in an automatic transmission" is correct is it????? If so do you also say that the other posts confirming that there is indeed a clutch mechanism even in an automatic transmission are also wrong? Do you also deny the exhistence of "wet-plate clutch" and "clutch packs" in an automatic transmission? Those are also incorrect is it?

To me the acronym "STFU" is raw filth unless it is seen as somthing "entertaining" by you. As to where the post containing the acronym "STFU" is, please roll back the pages on the thread and you will see it. BTW there were a few more expletives used in that posting which now have been taken off obviously "by those concerned" for obvious reasons and this one remaining may have been missed out on!

What irks me is the double standards adopted. "Sauce for the goose is sauce for the gander" isn't it?????

I am out of this thread!

Have nice day!

[chan5]

can somebody please shed some light on this "wet plate clutch" and "clutch pack" of automatic transmission in simple terms.

Little confusing since all i knew is there's torque converter instead of clutch...

[harshansenadhir]

can somebody please shed some light on this "wet plate clutch" and "clutch pack" of automatic transmission in simple terms.

Little confusing since all i knew is there's torque converter instead of clutch...

True, torque converter is there instead of dry clutch in a manual setup.

The wet clutch pack or friction plates are inside the gearbox and not necessarily does the job of dry clutch. As how i understood it does a job similar to synchronizers in a manual gearbox.

Basically this plate set transfers torque in the main shaft to gears in different occasions without any jerk in simple terms.