Trany Problem...Wont move in D

[Trevor]

Originally Posted by oab_au

Yes mate, I am saying that the one way clutch is slipping.

No mate, I can't provide a reason for the way its acting.

Probably the same reason it was working fine the day before it failed.
It did not break the one way clutch, it is just slipping. It may grip next time also, but as it has slipped, it will do it again.

Harvey.

Please explain exactly how a Sprague type clutch can slip and then again later grip.

The alignment of the drive elements and the whole purpose of the design is to transmit a solid drive in the nature of a ratchet. If it does not drive it is broken and can not slip at one time and drive the next.

[TomsSVX]

There is no manual operation in the gear box besides the parking prawl. The signal for line pressure is completely electrical. That is why I am suggesting a thorough inspection of the inhibitor switch as it control what your transmission is doing

Tom

[oab_au]

Originally Posted by TomsSVX

There is no manual operation in the gear box besides the parking prawl. The signal for line pressure is completely electrical. That is why I am suggesting a thorough inspection of the inhibitor switch as it control what your transmission is doing

Tom

Tom you must be joking, surely. I know that the Auto box is not your specialty, but you must have pulled the pan off one and seen the way the shift linkage that works the parking pawl also moves the Manual spool valve in the valve body.
Its the one that some people, that have removed the valve body, have not engaged, when they replaced it. You can see it on page 19 of book 3, fig26.

The TCU can't put this box in a forward or reverse gear, from Neutral. It would be a safety disaster to rely on the TCU to engage a forward or reverse gear from Neutral. The driver has to do it manually, with the shifter moving the manual valve.
There is no way the TCU can engage the forward or reverse clutches, it has no way of turning these on, it has to be done by shifting the manual spool valve.

When the lever is moved to R, the manual spool valve opens passages that direct Line pressure to the reverse clutch, to engage reverse gear.

When the lever is moved to D,3,2,1, the manual spool valve opens passages to direct line pressure to the forward clutch, to engage First gear.

In positions 3,2,1, it also engages the over-run clutch.
In position 1, it also engages the Low/Reverse brake, this is the one that prevents the 1/2 one-way clutch from slipping, that is happening in Pearlm30s case.
You can see this in WSM book 3, page 31, Manual valve.

I think I have answered Pearlm30 question, I can't add anything else that would help him, so I'll end here.

Harvey.

[TomsSVX]

Harvey, You are right, it does have a manual plunger... I guess I never notice it before I looked today when I had a pan down...

Besides that I also looked at my service manuals and saw a problem... IF the car does not move in 2, your logic may be correct in assuming the 1-2 clutch is slipping BUT he has stated before that it does.. Look again at the diagrams, it states that only in 1 that the low/reverse clutch is engaged. That meaning if the car operates properly in 2 that the theory that the one way 1-2 clutch is slipping would be incorrect... I am just trying to allow him to troubleshoot this without the assumption of the worst which may in-fact be incorrect.

Tom

[oab_au]

Originally Posted by TomsSVX

Harvey, You are right, it does have a manual plunger... I guess I never notice it before I looked today when I had a pan down...

Besides that I also looked at my service manuals and saw a problem... IF the car does not move in 2, your logic may be correct in assuming the 1-2 clutch is slipping BUT he has stated before that it does.. Look again at the diagrams, it states that only in 1 that the low/reverse clutch is engaged. That meaning if the car operates properly in 2 that the theory that the one way 1-2 clutch is slipping would be incorrect... I am just trying to allow him to troubleshoot this without the assumption of the worst which may in-fact be incorrect.

Tom

OK Tom, I think you may have been suffering a bit of "brain fade" after the weekend.

In second the Brake band is on, and that holds the front carrier still. The 3/4 one way then locks the front carrier and the rear ring gear to stop it from turning, so the 1/2 is not used.
Both one way clutches are used in D 1, the fact that it does have 2nd gear, in D or selected, shows that it is the 1/2 that is slipping, and not the 3/4.

Harvey.

[TomsSVX]

you are not listening. If you are claiming that the manual position in the transmission is determining whether or not the car will move, that is incorrect unless it has been dislodged or broken. Simply stating the brake band is not being used in the 2 position yet, it is still able to engage and drive normally. This is not a fight and I am not "hazy".

You even said it yourself right here

When the lever is moved to D,3,2,1, the manual spool valve opens passages to direct line pressure to the forward clutch, to engage First gear.

In positions 3,2,1, it also engages the over-run clutch.
In position 1, it also engages the Low/Reverse brake, this is the one that prevents the 1/2 one-way clutch from slipping, that is happening in Pearlm30s case.

In saying this, the only outstanding circumstance in which the clutch slip is overcome would be having the shifter in the 1 position. But infact it will work in 2 as well. Not to mention the fact that he has not had any discretions with shifting at all... So my assumptions remain as an electrical fault more than likely in the inhibitor switch.

Tom

[Trevor]

pearlm30, please do not despair.

Nothing you have reported to date indicates that bad things are afoot which could be damaging something. Continue experimenting and advise in full regarding any and all outcome.

Meantime you are among many friends all willing to assist.

[oab_au]

OK I Have finished with this thread.

Harvey.

[TomsSVX]

Pearlm30, Pm me for more info or if you need my Phone #

unsubscribed...

Tom

[pearlm30]

Hi everyone
Didnt expect to see my problems turn into some heated discussion
I am not really familiar with detailed transmission mech. and some of the advice are really technical in nature.
I am sorry if my reponses are not to the point and or confussing.
I really appreciate everything.

[Trevor]

Originally Posted by pearlm30

Hi everyone
Didnt expect to see my problems turn into some heated discussion
I am not really familiar with detailed transmission mech. and some of the advice are really technical in nature.
I am sorry if my reponses are not to the point and or confussing.
I really appreciate everything.

You have nothing to be sorry about, but just the opposite. You provided exact information regarding a strangely perplexing problem. The evidence is clear. Confounded errors were not of your doing.

P.S. Please stick with it. The information gleaned will be of value to all and greatly appreciated.

[RSVX]

This thread has gone a foul. The Admins/Mods (Read: More than ONE) are looking into the events that have taken place here and will be taking the appropriate action in accordance with the rule set in place.

This action will not be coming from me, but the Admin/Mod staff as a whole.

[ensteele]

The thread was closed because one member personally attacked another. You can disagree with someone, but do not personally attack someone just because you disagree. If you do, you will be warned and if it continues, a time out will be given.

I will leave this thread open for now, but it it gets out of hand again, it will be closed. Thanks for your cooperation.

[RSVX]

Originally Posted by RSVX

This thread has gone a foul. The Admins/Mods (Read: More than ONE) are looking into the events that have taken place here and will be taking the appropriate action in accordance with the rule set in place.

This action will not be coming from me, but the Admin/Mod staff as a whole.

Originally Posted by ensteele

The thread was closed because one member personally attacked another. You can disagree with someone, but do not personally attack someone just because you disagree. If you do, you will be warned and if it continues, a time out will be given.

I will leave this thread open for now, but it it gets out of hand again, it will be closed. Thanks for your cooperation.

I have removed any and all posts from this thread that violate our well published rule set.

I am sorry to say that some very useful information has been moved along with the offending material. It would be too difficult for the Admin/Mod staff to disect the posts and remove only the offensive pieces.

In the future, if you dont want your valid troubleshooting help removed, you need to learn to conduct yourself like an adult and abide by our rules when you post or the ENTIRE POST will be removed.

[Trevor]

I apologise unreservedly towards any members I may have unintentionally upset.

However, I become very irritated when those who claim special credentials post in absolute terms advice in error, when this is detrimental to members and could involve them in considerable strife.

The patronising insinuating threat by way of personal instruction, now directed towards me, has an unfortunate overtone and I contend is in spirit, exactly against the rules i.e., --- First and foremost, please treat all members with the same amount of respect you wish to receive.

“In the future, if you dont want your valid troubleshooting help removed, you need to learn to conduct yourself like an adult”

N.B. Most will know that in no respect am I childish. I am 79 years old.

Sincerely, Trevor.