[eDubz]

'13 X3 35i MSport with 110k miles...

I have no record of any fluids being changed on the vehicle, so I'd like to flush the following fluids as preventative maintenance:

*brake (also changing all 4 pads/rotors/sensors)
*coolant
*transmission
*rear-diff

Does anyone have DIY guides and/or links to the proper fluids? I'm trying to gather info and parts so I can knock it all out at the same time.

Appreciate any guidance!

[BIG_KID]

Brake: while doing the pads, open the bleeder valve then push the piston back. This will keep all the nasty fluid from going back into the system. The rears are a bit tricky as they have the electric emergency brakes. There is a good video on you tube for this. When done with the brakes just open the bleeders and let it gravity bleed out. Uses dot 4 fluid.

Transmission: you will drain out about 4.5-5L the filter is part of the pan. The refill procedure can be a bit tricky and over engineered. I just refill with engine running on level ground until it comes out the fill port. Use only ZF lifeguard 8 fluid.

Rear end: there is no drain, you will need something to suck out the old fluid then refill with new.

Coolant: haven't cahange mine so I dunno

[Wgosma]

Consider adding transfer case fluid drain/fill. Best to reset the adaptations after new fluid- need scan tool.

Coolant: not done mine yet but based on past experience remove lower radiator hose is typically best drain point.

Should be procedures at newtis.info.
Good luck/Bill

[Bilbofraggins]

Some good points passed..

brake (also changing all 4 pads/rotors/sensors) - Go with BREMBO, particularly in the snow zone!
*coolant (G-48, say ZEREX etc)
*transmission ) Although last time around I stayed with ZF stuff, I researched the hell out of this....and would try an alternative based on the spec...in this case it's Shell M-L12108)
*rear-diff (Front or rear 75w85 Hypoid Gear Oil (GL4)...if you buy GL4/5 compatible..Too easy.

Transfer case - Ravenol TF0870

Take a look at specchart.com if you haven't already....

I had my normal indy do my tranny drain, filter/gasket change and fill....new pan bolts are a must. Or you will learn the hard way. I then had the level verified at a tranny specialist...cost me 30 mins labor...they added .25litre. Next time I'm doing it all myself.

Here is an actual ZF video on the tranny:

Good luck.

[Bilbofraggins]

Some tranny fluid info here worth a look:

https://www.audiworld.com/forums/a8-...truth-2882676/

There's always been a lot of confusion and misinformation posted about this so I thought I'd contribute some new information I've recently found out on the topic. It's a long post but hopefully worth the read.

Setting the scene

The 6-speed 09E transmission as used in all quattro D3 A8's is actually a ZF 6HP26 (6HP19 for smaller engine versions) unit. The quattro drivetrain parts (TORSEN center diff, drive shafts and front diff) are all bolt on accessories to this core transmission. The ZF 6HP range of transmissions is used by many OEM's ranging from Rolls-Royce to Hyundai, and is on the whole a very strong and reliable unit.

The official line from both ZF and Audi (and all other OEM's) is that the units are maintenance free and have a lifetime ATF fill. What "lifetime" actually means has never been quantified. However problems with the transmission developing a "hoot" noise when changing between gears 3-4 has become a common issue for many owners. The official service remedy from all OEM's affected has been to change the transmission fluid. The details of the Audi specific TSB for this can be found here, but it's essentially still just a fluid change rolled in with a software update that later cars had from the factory anyway.

Because this was a widespread issue, ZF changed their position on the lifetime fill specification for the 6HP. They now somewhat sneakily advise that "depending on driving style", the transmission fluid should be replaced every 8 years or 80k miles to maintain optimum performance. See here for the the official ZF Service Bulletin on the matter.

Despite this, Audi has not changed their position on the "lifetime" ATF. Therefore it would seem that Audi regard 8yrs/80k miles as beyond "lifetime".

Transmission Fluid / ATF Specs

So that brings us to the topic of ATF for the 6HP.

The official line from ZF is that only their "Lifeguard " branded ATF, or vehicle OEM equivalents can be used (e.g. VW G055 005), with a stern warning that other fluids will damage the transmission. The ZF specification group that these ATFs come under is ZF TE-ML 11.

However the Lifeguard 6 ATF variant (aka LF6, VW G055 005) used in most applications of the 6HP is unreasonably expensive. So over the years it's become clear that the base quality/spec standard is Shell ATF M-1375.4, and below are some of the numerous cheaper equivalent options that are available now:

Redline D6 ATF
Liqui Moly Top Tec 1800
Shell Spirax S4 ATF MSP
Mercon SP
Ardeca Matic +Z6
Motul ATF VI
Ravenol ATF 6HP
Anything else that meets the Shell ATF M-1375.4 specs

Some models specify a different fluid, namely the W12, and the 6 cyl models using the 6HP19 lower torque capacity version. Initially this was Lifeguard 6+ (VW G055162A2) which was blue in colour and has been discontinued. It was rebranded to coincide with the new range of 8-speed 8HP transmissions as Lifeguard 8 (VW G060162A2) and the colour changed to green. It's the same stuff though, just dyed green instead.

The base specification for this is Shell ATF M-L12108 So suitable equivalents to VW G055162A2, VW G060162A2, LF8 are:
Ravenol ATF 8HP
Ardeca Matic 8HP
Redline D6 ATF
Not as many obvious ones as it's a newer product, but anything that meets Shell M-L12108 is the key

So far I have not shared any new information, or knowledge that's not readily available. But I recently found out some very interesting new info on the topic.

You're probably thinking who the heck are Ardeca? Well they are a Lube company from Belgium, and they had a stand at the recent Automechanika 2015 tradeshow in Chicago that I attended. As did ZF.

ZF were exhibiting their ATF service kits and when I inquired further, the reps were towing the official "depending on driving style" line about ATF changes. However when I pressed them on it, they tacitly admitted that 80k miles is when you should do an ATF change on the 6HP, regardless. They would not however be drawn on any equivalents to LF6, stating that only LF6 (or LF8 depending on application) has the correct composition and additive packs to not damage the transmission. There are stern warnings stating this both in ZF literature and also on the labels of LF6 bottles.

So moving on, I got talking to the guys on the Ardeca Lubricants stand as they had a product (MATIC +Z6) that specifically stated was for the ZF 6HP. As it turned out I was talking to the head of Ardeca and I asked him how he can be selling an ATF labelled as specifically for the the ZF 6HP, when ZF, just 3 stands away said there are no LF6 equivalents, and anything else will cause damage.

He laughed and said it was simply nonsense and scaremongering by ZF. He went on to confirm that the base specification is Shell M-1375.4, and that until a few years ago, ZF held the licence on the additive pack for M-1375.4. Consequently they licensed it out to ATF makers for an extortionate sum. As it happens, most OEM specific ATF (e.g. VW G055 005) for the 6HP is not repackaged Lifeguard 6, rather an equivalent made to the same M-1375.4 specs. He said that his company itself had to pay this licence to fee to ZF for the additive pack for many years, which in turn made their ZF LF6 equivalent very expensive back in the day.

He then went on to explain that the ZF licence for the Shell M-1375.4 additive pack is no longer valid and the "recipe" is now freely available on the open market. Hence why there are now numerous ATF's out there that claim to be LF6 equivalents but for a fraction of the price. And here's the kicker, he said that it can be dyed any color you like, green, blue, red, whatever...

So there you have it. Draw your own conclusions, but for me the overwhelming evidence points me well away from the belief that LF6 is anything special, or worth paying any sort of premium for.

Happy DIY ATF changes for less than 75 bucks!

ETA: I've since done a fluid and filter change using Redline D6 and it improved things considerably. https://www.audiworld.com/forums/a8-...ected-2883008/

[Bilbofraggins]

And good for a laugh: https://www.oildepot.ca/dodge-dealer...000-atf-flush/

[eDubz]

Awesome info - thanks guys!