O Ring

[Singh]

Someone posted this image of the O Ring below on TSN, is this from the Audi UK service procedure? After speaking to Chester Auto Transmissions I am really worried that they have not changed it and have been on the phone to the Audi A8 team, apperently the service manager did not even know what an 'O Ring' was.

[Conan_the_Librarian]

Singh,

This subject has come up derveral times on TSN. Without the o-ring there is a danger of the pump loosing vacumn and cavitation occuring. Pressure is lost withing the transmission and damage occurs.

There is only one way to find out if it is there!

You''l have to open her up to confirm it's prescence.

If however, you have no transmission issues then it's likely it is not missing. A careful watch is needed.

The picture is from the Bently on-line service manual. Audi don't have a service procedure for the 5 speed boxes. Sealed for Life!!!! Although they do have an exploded diagram in ELSAWIN with accompying directions or disassembly and reasembly.

[Singh]

Thanks Mike, box has started to feel funny now. It was ever so smooth before the change, they did not change the o ring when they done the oil change as they did not even know what it was. I'm not sure what steps to take now as they say they have followed the Audi procedure. I may ask ZF what there view is on the O Ring and get back to Audi.

[Conan_the_Librarian]

I can confirm that the audi manual says always replace. Remember the manual is directed toward rebuilding the box after disassemble. The reasembly procedure is always to replace the o-ring. Always.

To change the filter you must dissasemble the component parts, therefore the re-asemble procedure has to be followed.

From the way you say it, they may not have replaced the o-ring. That dosent mean they haven't refitted the old one. If that's the case then I would ask them 'did you re-fit the old o-ring or replace it with a new one'. Do it in writing as evoidence trail. I will try to find the Audi re-assemble procedure when I get home.

What warranty did they give on their workmanship?

[Architex_mA8tey]

Am I missing something here chaps? I thought that the method that Chester Auto Transmissions used was different ie. they used a special pump thingy to suck out the fluid while replacing it at the same time (like a heart transplant!)
If that is the case then will they have taken everything/anything apart and cleaned off magnet filters and replaced gaskets and o-rings even at all?

[Singh]

Interesting point Architex, Mike. If you could get the Audi version that would be brilliant. Just what I need to show them to make them sort my box out. The warranty would be the standard Audi one on parts 24 months?

[Conan_the_Librarian]

Originally Posted by Architex_mA8tey

Am I missing something here chaps? I thought that the method that Chester Auto Transmissions used was different ie. they used a special pump thingy to suck out the fluid while replacing it at the same time (like a heart transplant!)
If that is the case then will they have taken everything/anything apart and cleaned off magnet filters and replaced gaskets and o-rings even at all?

While I believe that is what they do. It would be pointles if they had not changed the filter (blocked filters cause cavitation) of cleaned the sump magnets first. For which it is off sump and out filter.

Originally Posted by Singh

Interesting point Architex, Mike. If you could get the Audi version that would be brilliant. Just what I need to show them to make them sort my box out. The warranty would be the standard Audi one on parts 24 months?

An Audi warranty by Chester Auto Transmisions? If you have an Audi warranty on the car they won't guarantee a third parties work. Have Chester Auto's given you a guatantee?

[Singh]

I think you have misunderstood and looking back at my first post I can see why.
The work was done at Audi, I just spoke to Chester Auto transmissions about the importance of the O Ring and if my gearbox was now in danger as Audi hadn't replaced it.

[Conan_the_Librarian]

ere we go....
Automatic Gearbox 01L, Four-wheel Drive Removing and installing oil pan, ATF screen and valve body
Removing and installing oil pan
Removing

• ‒ Place container under the gearbox.

• ‒ → Unscrew the ATF drain plug -1- and drain off ATF.

Note:
A small quantity of ATF will remain in the oil pan.

• ‒ Unscrew oil pan bolts working diagonally.
• ‒ Remove the oil pan.

Note:
Clean the solenoids in the oil pan (4 off). Ensure that the solenoid is in full contact with the oil pan
Installing
Install in reverse order. The following steps must also be performed.
Note:
The drain plug with sealing ring must be replaced.

• ‒ Replace gaskets and seals.
• ‒ Tighten oil pan bolts, working diagonally in several stages.
• ‒ Changing the ATF or filling after repair work => Page 37-65.

Tightening torques
Component
Tightening torque
Drain plug in oil pan
12 Nm
Oil pan to gearbox housing (working diagonally)
10 Nm


Automatic Gearbox 01L, Four-wheel Drive Removing and installing oil pan, ATF screen and valve body
Removing and installing ATF screen
Removing

• ‒ Remove oil pan => Page 38-9.
• ‒ → Unscrew the two ATF screen bolts -arrows-
• ‒ Pull ATF screen off valve body.

Installing

• ‒ Apply a thin coating of ATF to the seal around the suction collar of the ATF screen.
• ‒ Bolt on the ATF screen.
• ‒ Installing oil pan => Page 38-10
• ‒ Changing the ATF or filling after repair work => Page 37-65.

Tightening torques
Component
Tightening torque
ATF screen to valve body
5 Nm
Oil pan to gearbox housing (working diagonally)
10 Nm


Important bit emboldened....

The diagrams
Part 29 is the critical one

I was going to say.. I remember your horry story with Audi, and Chester Trans have had great write ups on TSN for service. They do indeed suck and replace via the cooler.