i understand that the trannie fluid requires periodic changing. i have 2 questions in that regard:

1) opinios as to whether a flush as good or better that a "usual" drop the pan, etc, and refill?

2) i notice quite a number of recommended ATFs, depending on trannie model and with quite a variance in price, the oem "audi" being quite costly. does anyone have a list of acceptable atfs for a 2005 A8L?

 

The fluid and needs to be changed around 100K and you should be checking the trans level and for leaks periodically along the way.

You can't flush it so don't try or let anyone try for that matter.

The fluid is mineral based for what the transmission is worth just buy the Audi fluid and that's that. Remember Your driving a $70,000.00 car your supposed to act like you got the Bread Baby!!!

I have Pentosin in both my cars and it works fine not much cheaper though.

You should find a real reputable indy shop

THE EASY PART
The car goes up in the air
Pan comes off and fluid drained from pan
Filter and gasket are replaced and pan cleaned and re-installed
Fluid is fill from the bottom at the pan

THE HARD PART
Connect a VAG-COM to the car so you can monitor the temp of the transmission.

Start the car and shift into each gear for 10 seconds while it is in the air

Then remove the fill plug and begin filling by means of a gravity feed reservoir with preheated fluid while the car is running on top of you.

When the fluid begins to spill out and the temp reaches 32-34 degrees Celcius the trans is full and you immediately re-install the plug. If it reaches 32-34 Degrees Celcius and it is not spilling it is not full yet. You can't go beyond 34C or the measurement will be off.

After that you might as well change the rear seal on the transmission output shaft. If it's not leaking it either has no oil in it or it will be soon.

That's some info to quiz your mechanic with to see if he knows how to do it.

It's a PITA to learn and I don't recommend you learn on your own car
I also do not recommend bringing it to Audi They did mine wrong and under filled them both!!! they didn't forget to charge me though 500 each

 

Not bein picky..yeah I am But, skip a little step there ? ...or maybe not(?): "Fluid is fill from the bottom at the pan" (easy part)

Hard Part: Fill pan till overflow first....before Vag & starting engine, then go thru gears, continue filling, etc. ??

-- Bentley, AudiPages, ZF pdf instuctions:

http://www.zf.com/na/content/media/u...ars/5HP24A.pdf
Page # 4

 

i note the hyperlink is to a ZF manual which refers to the 04 model year A8 as the last year to which it applies, with a 5 speed trannie. as the 05 has a 6 speed, are the proceedures, transmission model numbers, etc. changed in some other manual?

also, the prior poster indicated that one can't flush the tranmission. i wonder if this is correct. i jave an 04 phaeton with a 5 speed ZF transmission and the service people at an independent facility (allegedly) were able to perform a flush. it was suggested that a flush is better because, while the filter isn't changed, etc. more fluid is replaced as that in the torque converter is also drained and the slight pressure of passing the fluid through the system may clean the filter a bit if indeed there is contamination on it.

 

That is a great link Thanks!

I was just giving you a basic idea of what's involved so you can interview potential mechanics to be sure they know.

Not many people know how to perform this service and your trans is very very expensive if they mess up!!! Audi themselves under-filled my A6 and did not replace the filter on my A8 do not go there!!!

This is an advanced project and took me several attempts to get the process down. It is not a simple drain and fill oil change. It's worth letting someone that knows the process do it for you.

However if your interested in punishing yourself like the rest of us and your going to attempt it yourself let me know or PM me.

You will need the vag-com, jack stands, filter, gasket, fluid (about 8-10 qts which includes some extra in case you spill or mess up) some sort of gravity feed fill reservoir, a thermometer to measure the temp of the fluid you intend to fill the trans with. Some method of warming the fluid up. A 17mm allen/hex socket and a breaker bar, metric sockets etc.. and in the worst case scenario extra pan bolts and ability to extract broken pan bolts / tap and chase the threads. If you do everything correctly it will take a few hours anything goes wrong- all weekend.

There are kits you can purchase at www.blauparts.com
It comes with directions that are not 100% correct.
You must order an addition 2-3 qts because the kit does not include enough.
it comes with a pump so you can pump the fluid in this is fine for the preliminary fill but you need to slowly top it off with fluid at as close to 30 Degrees Celsius as you can get because hot and cold fluid do not mix well. That's where the gravity feed res comes in handy.

IMO this is a better project to do in colder weather, not summer.

 

<QUOTE> 01-06-2011, 10:49 AM

"calmone

i note the hyperlink is to a ZF manual which refers to the 04 model year A8 as the last year to which it applies, with a 5 speed trannie. as the 05 has a 6 speed, are the proceedures, transmission model numbers, etc. changed in some other manual?

also, the prior poster indicated that one can't flush the tranmission. i wonder if this is correct. i jave an 04 phaeton with a 5 speed ZF transmission and the service people at an independent facility (allegedly) were able to perform a flush. it was suggested that a flush is better because, while the filter isn't changed, etc. more fluid is replaced as that in the torque converter is also drained and the slight pressure of passing the fluid through the system may clean the filter a bit if indeed there is contamination on it." < QUOTE>


I believe the ATF and filter change procedures remain the same.

As I understand, (and according Bentley) the torque converter can only be drained by removing it from the trans, thus the "no true flush" statement, with an installed trans.

A filter could NOT be cleaned (even partially) by an attempted a full flush...it's only pushing ATF through the filter the same direction and debris can NOT pass all the way through a proper filter.
I would NOT bother with an ATF change unless I was changing the filter, also...what I consider THE most important part of the procedure (that and cleaning sludge out of the pan)...takes work load off the pump.
In fact, changing fluid without a filter change, will clog the filter further...new clean ATF will introduce new detergents, breaking loose more debris from clutches, etc, which have nowhere to go but the filter.

Also, there is a philosophy (not universal, but makes logical sense) that attempting thorough flushing of a high mileage trans (or even introducing new ATF), which has not had regular ATF service, will actually cause the trans to fail earlier. Material builds up on clutches over time which can actually have a beneficial friction effect during normal operation. New ATF detergents can wash this away and have a negative/slipping effect on older worn parts that were depending on the build-up.
Some have even simply changed the filter (THE most universally accepted GOOD thing) and cleaned out pan sludge (also recommended, since bottom sludge serves no purpose by any philosophy...it's not helping any moving part and is in danger of being picked up and further clogging the filter)... then returned the old used ATF fluid back to the system, avoiding the chance of messing with something that was working fine, but taking the clogged filter load off the pump.
Many are also of the belief that after significantly high mileage, don't do any service at all, if everything is working correctly with no symptoms.
I've seen the same model trans fail at the same high mileage (185K miles) in 2 same model D2's...one with every 30K mile service and the other with no service at all.

 

Yeah i remember going thru the motions with Jackmup about this. ZF transmissions are a bitch to fill correctly. If you do it exactly as ZF says you will end up with an underfilled transmission almost everytime. Audi has directions that closely relate to Jackmup's explaination, once the fluid reaches 25 degrees celcius you need to be filling the transmission like crazy while going thru the gears. If you don't get at least 6 liters in there by 30 degrees celcius it will get too hot and spill out before you get it full. I've gone round and round with these things, its the only way to do it right.

The first time you drive it you'll know you don't have enough fluid in it LOL!

 

while i get my head in place, for an 08 i just recaslled that i am not certain when the transmission fluid change is recommended!! someone mentioned 100,000 miles, but i seem to recall a lesser number????

 

According to audi its a lifetime fluid. Personally i would change the fluid/filter every 60-80k and get fresh pan gasket on there to avoid leaks, just don't flush it with anything, solvents are the leading cause of grenading a trans.

 

oh, "lifetime" fluid? i always questioned that idea. on the phaeton, both the 5 speed trannie on the w12 and the 6 speed on the 4.2 v8s came with "lifetime" fluid. both are ZF units, i always presumed the 6 speed units were the same for the 4.2 liter phaetons and audis. about 2 years ago vw issued a tsb for the 5 speed units, now it was recommended that the fluid be changed every 20k. the word on the phaeton forum is that while the "lifetime" claim for the 6 speed unit hasn't changed, vw has issued an extended warrenty for a particular part of the unit for 7 years/ 100 thousand miles. go figure.