2001 Audi S8 Gearbox Service
 

I've just taken ownership of an S8 D2 (77k miles) and would like to service the gearbox. I've booked it into Quattro-Tech who seem very knowledgeable and well reviewed. I live in Rushden (Northants). Any thoughts?

As you know there's 2 approaches to doing this - the proper machine generally only available through ZF specialists and not at indy Audi specialists, or the drop the sump and filter out and drain what you can.

The former is clearly preferable, if you have someone local that can do it at reasonable cost.

The latter is fine if the oil isn't completely ruined and you can live with a litre or so that stays in the torque converter. Aim to repeat the exercise a couple of years down the line and it should be pretty much all changed.

Also, I think Ainars (ainarssems) lives near Rushden, might be worth dropping him a PM if he doesn't spot this and reply. ;)
Edit: Looks like he's on the case already. :ROFL:

Cannot say much about gearbox servicing or the local garages because I do most of the stuff on car myself and have not done anything to the gearbox. Only garages I use is Orbit in Rushden for wheel alignment and Kilby Motors in Irtlingborough for MOT's, tyre mounting, balancing and some odd job like taking a wheel hub to them to press the bearing in and out. Seeing that some gearboxes have failed soon after fluid change I am inclined to leave mine well alone and let it run until it dies as I only paid £2.5k for the car in 2008 and it has been Cat B write-off in 2007. If the gearbox fails it will be either DIY repair to the box, manual conversion or scrap it.

Has a box failed after being serviced 'properly'? I've read of failures after a DIY or non-ZF specialist garage fluid change and this has been attributed to "disturbing the gunge" and not flushing it out. But I don't recall a failure after having it done properly.

I get mine serviced every other year - properly - and I have 165K on the clock.

I don't know of any that has been regularly serviced every 40k miles that has failed and if the gearbox has service history or has recently been replaced or refurbished I am all for continuing to service it.

But in my case it is now over 18 years old and done over 140k without touching it so I better leave it alone. No flushing equipment will get gunge out in 10 minutes if there is any, it will slowly dissolve over weeks or months. If it dissolves very slowly it's not much of a problem, if the solvent washes it off in lumps that's when it becomes a problem. The rubber seals could be dried out and can soak up too much of solvents and conditioners from new oil, become too soft and brittle and fail. It may well be that oil change will not do any harm (or good) but just that gearbox at this age could be about to fail anyway. At this point I better save £250 that it would cost to service it and put it towards rebuild if necessary. Going DIY it could probably be repaired for under £500 if needs be. I am tempted to slowly introduce fresh oil to slowly wash away gunk and condition seals maybe drain 2 litres of oil and refill. I do have a bit of oil I got from Sarg in one of the meets.

Yes - mine, after Chester Autos serviced it.

What happened?

It started slipping as soon as the gearbox had been flushed out by Chester Transmissions, using their "sucky-pumpy thing". So I then ended up nursing it - very, very carefully - up the M6 and M74 to Mackies in Glasgow, who rebuilt it, and it's been serviced regularly since then with no problems over the last three years.

So I'd sort of agree with Ainar - either leave it till it breaks, or take it somewhere where they can fix it properly if it goes wrong, and be prepared to write a large cheque in that case!

I have had a look in the net and the ZF training video https://youtu.be/S8jcRd4gyWc seems to suggest that the pan off and filter change seems acceptable to ZF. As I understand it, the S8 has the ZFHP524, whereas my previous 530i had the '19.

If you speak to Air con specialists, they all use automated machines, but that is to save time. Could the same apply to flushing machines?