What gearbox/transmission service on my S5 B8.5?

[Arese]

Hi everyone,

My 2016 S5 B8.5 is reaching 55,000km so it's time to think about gearbox & transmission service.
The thing is that I never owned a performance car where gearbox & transmission oil needed to be serviced so I'm still a bit confused about what needs to be done.
Going off my Audi Service schedule book



- I've got an S-tronic gearbox (so it says on my Audi invoice) so can I go ahead and ignore the ATF multitronic gearbox service mentioned in the booklet?

- I'm not familiar with this Haldex coupling system. Is it fitted to my car?
I did some research and it's apparently some sort of all-wheel drive system where it temporarily sends power to the rear wheels when the front wheels lose traction making it not a "real AWD system" and often badged 4motion on VW cars. But I read online that even some Audi badged "Quattro" are equipped with this haldex system sometimes.
My question is, does my car fitted with a Haldex system? How can I know for sure what Quattro system I have?

- With regard to the sport differential, it says Audi RS5 only but I believe it was an option for S5 cars as many people online recommended me to get an S5 with a sport differential. I'm not entirely sure if my car has got it. I've got my Audi service book with all the optional equipment codes. Can I figure it out based on those codes?

That's the only points in the service schedule I'm not sure of, it would be great if someone could clarify those for me so I can properly maintain my S5.

Otherwise, I've already serviced the S-Tronic DSG including external/internal filters, engine oil, engine oil filter, air filter, cabin filter, brake fluid, and planning to replace all spark plugs soon.

Thank you

[hahnmgh63]

The S-Tronic (DSG) gearbox has a MTF (Manual Transmission Fluid) & ATF (Automatic Transmission Fluid) (BTW, so does a Sport Diff). For the S5 Audi only says to replace the ATF in the DSG but not the MTF. The RS5 has basically the same transmission and Audi says to do both? Most would say if you want to keep your car in great condition, do both. Haldex is only for the TT & 3 series cars (A3, S3, RS3) with transverse mounted engines. For the rear it depends on what you have. The sticker in the trunk/spare tire wheel well will have your options codes with your engine, transmission, and rear Diff codes, the sticker is also mounted on the inside front page of the Mx booklet that comes with the car too. Regular diff just has gear oil and like any regular diff just takes 75w/90 Synthetic GL5 gear oil. The Sport Diff as I mentioned above has a ATF side and MTF side. Once again the RS5 gets both sides changed and the S5 doesn't. Do both sides, it doesn't take a whole lot of fluid. Keep in mind a transmission and/or Diff are a fortune to replace so a little Mx is great. Audi's service intervals should only be considered Maximun intervals, most change these, including the engine oil, more often. Cheap insurance.

Great thread here: https://www.audizine.com/forum/showt...ht=DSG+Service

[Arese]

The S-Tronic (DSG) gearbox has a MTF (Manual Transmission Fluid) & ATF (Automatic Transmission Fluid) (BTW, so does a Sport Diff). For the S5 Audi only says to replace the ATF in the DSG but not the MTF. The RS5 has basically the same transmission and Audi says to do both? Most would say if you want to keep your car in great condition, do both. Haldex is only for the TT & 3 series cars (A3, S3, RS3) with transverse mounted engines. For the rear it depends on what you have. The sticker in the trunk/spare tire wheel well will have your options codes with your engine, transmission, and rear Diff codes, the sticker is also mounted on the inside front page of the Mx booklet that comes with the car too. Regular diff just has gear oil and like any regular diff just takes 75w/90 Synthetic GL5 gear oil. The Sport Diff as I mentioned above has a ATF side and MTF side. Once again the RS5 gets both sides changed and the S5 doesn't. Do both sides, it doesn't take a whole lot of fluid. Keep in mind a transmission and/or Diff are a fortune to replace so a little Mx is great. Audi's service intervals should only be considered Maximun intervals, most change these, including the engine oil, more often. Cheap insurance.

Great thread here: https://www.audizine.com/forum/showt...ht=DSG+Service

Thank you for the detailed answer and for the link, great thread it looks super detailed, I'll review it a bit later once I figured out my car's configuration.

Here's the sticker from the booklet.
I think I don't have the sports differential because I saw someone saying that If I had it, I would see a Sports Differential option under the Audi Drive menu and I don't have it.



So if you confirm with my sticker that I don't have the Sport Diff, that would mean that I need to change:

- S-Tronic DSG ATF & MTF
- Rear Diff Gearl Oil

And that would be a complete transmission/gearbox service on my car?

Thanks again for all the insights, much appreciated

EDIT: Ok I continued researching the topic and I found out what was confusing me.
Gearbox and transmissions are the same things. I thought it was 2 different parts that's why I was confused reading about the S-tronic, some people would use the term gearbox, and other people would use the term transmission.
Apparently, Americans call it transmission, and the English a gearbox.

Ok so basically there are 2 elements to service. The transmission/gearbox (S-tronic DSG in my case with ATF and MTF) and the rear differential (with normal gear oil if normal differential, and MTF & ATF if sport differential)
Does that sound correct?

[Smac770]

Unfortunately, the GH_ code (GH0 = no rear diff, GH1 = standard open rear diff, GH2 = sport open rear diff, GH3 = locking rear diff (R8), GH4 = quattro ultra open rear diff) rarely makes it onto the abbreviated PR codes list on the vehicle identification sticker.

type 0B5 = 7-speed DCT, aka "DL501"
type 0BC = open rear diff
type 0BF = sport rear diff

No GH_ PR code, but you have the rear diff code on the sticker: JKS. That's a type 0BC standard open rear diff. If you had the type 0BF sport open rear diff, you'd have rear diff code MKX. PWW is the code for your type 0B5 transmission. And CREC is the code for your 3.0T engine.

The 0B5 ATF is the normally required change item. The 0B5 MTF is only quoted for the RS model. But doesn't hurt to do it. Same for the 0BC rear diff gear oil in an A/S model.

A 2016 should have the 0B5 with the external replaceable ATF filter, so be sure to change that too. 18 and 19 in https://audi.7zap.com/en/rdw/audi+a5.../3/317-317054/

[Smac770]

The "gearbox" to me is specifically the gear mechanisms. The DL501 DCT has the dual-clutch unit, the mechatronics, the gearbox, the center diff, and the front diff (and the front driveshaft, technically). I could see the Brits just calling the whole thing a gearbox, as they are much more prominent with manual transmissions that have little more than a clutch and a gearbox (though not in an Audi, where the front diff and front driveshaft are always part of the composite transmission unit).

[Dippy]

@Smac770 - automatics are more common in the UK than you think, however most Brits would stop at "thing" and have no clue it is called a gearbox no matter what type the transmission is.

@Arese - you have the PR same code as my car - OG7 which is for "tiptronic" but which is definitely not the transmission we have. Further to what @Smac770 has advised, I think you ought to be aware that the 0B5 has a checkered history. The first version clearly had some faults and many owners suffered as a result. Audi revised it twice and the latest version for the B8 went into production in 2013. Now it is always difficult to make conclusions from fault reports on web forums, but it does seem to me that some of the problems owners have see can at least partly be attributed to late servicing. It is therefore partly because of these reasons that some owners, including me, will service ours more than the Audi recommendation.

As per your service book the only servicing which Audi recommend for your car is ATF (oil) and filter every 60k. That is indeed the minimum you should follow.

However as @Smac770 pointed out, the RS5 has the same transmission and Audi state that the "mechanical part" needs to be serviced at 30k. This means the gear oil. The assumption is that an RS5 transmission has a harsher life than an S5 transmission.

FYI my car has just done about 40,000km and it has had the s-tronic ATF service twice, the gear oil once, and the sports diff (ATF & gear) once. This is because I have a stage 2 tune and to me the service cost is negligible in comparison to the cost and hassle of having problems with these critical components.

BTW if you want to get "non-service" servicing done (e.g. S5 s-tronic gear oil) sometimes your only option is going indie because many Audi dealers cannot cope with the concept.

[Smac770]

The RS4/RS5 version of the DL501 got the crown gear center diff, which was more sensitive to clean oil than Torsen (the center diff in the DL501 being oiled by the gearbox MTF).

Audi also quoted the higher temps and thus oil wear in the diffs expected from track use (being an RS) as why the front and rear diff is on the schedule for the RS but not the S (the front diff in the DL501 being oiled by the gearbox MTF; and all RS5 having the 0BF sport diff with ATF and MTF sections).

[hahnmgh63]

That's all good info posted by others above. Yes, the JKS is the standard Diff and according to Audi is rated at 0.9ltrs of gear oil. Some in America call it a gearbox or transmission interchangeable. Maybe gearbox more common for a manual but used interchangeably. Or people will just ask do you have an Auto or Manual. They would call the DSG a Automatic transmission even though it is kind of two manuals in one with an automated function. As Dippy has said, please change your fluids more often than Audi says. They don't really care about your car once it's out of warranty.

[Arese]

Thanks everyone for all the great insights.
I've thoroughly reviewed the Audizine thread that was posted above which was of great help in getting all the right parts and understanding how to do the job.

For the ATF side of things, all the steps are pretty clear, I can picture the whole process in my head, and I have written down all the steps including the VCDS clutch adaptation process so I'm ready to go.

Before I start the job, I realized that I focused on reading about the ATF oil change but not so much on how to do the oil change for the standard rear differential (No ATF on the standard diff) and for the MTF side of the transmission.

Could someone tell me if the below steps are the right way to proceed? Interestingly enough I wasn't able to find 1 video on youtube showing how to do the MTF side of the transmission, all the videos only cover the ATF side.

- Standard Rear Diff
1. Crack open Fill plug first
2. Crack open Drain plug and drain gear oil
3. Install Drain plug, torque to spec
4. Fill diff with gear oil until it starts dripping from the fill hole
5. Install fill plug torque to spec
Do I need to bleed the system by running the engine? Check fill hole with engine on and add more gear oil if it's not dripping out or is it unnecessary for the standard diff?

- Transmission MTF
1. Crack open Fill plug first
2. Crack open Drain plug and drain MTF
3. Install Drain plug, torque to spec
4. Fill MTF chamber with until it starts dripping from the fill hole
5. Install fill plug torque to spec
Same question here, Does the MTF need to be bled or is it good practice to start the car, go through all the gears and then go back underneath, open the fill plug and check if oil is dripping and if not add more oil until it drips?

Just want to confirm the process for the standard rear diff and transmission MTF side and I'm good to go. I already received all the parts + OEM oil.

Thanks

[Smac770]

If you have the normal rear diff, then it's pretty simple. Process as you listed is all. No reference to any bleed process in the workshop manual. I'd just give it time to settle in, maybe manually turn the wheels to get some motion in there if you want to (I'd have it up on quickjacks, so that's easy enough to do). But if you want to run it around a bit and then lift it and recheck, that's a perfectly fine approach.

Got no idea on the 0B5 MTF process.

[Arese]

If you have the normal rear diff, then it's pretty simple. Process as you listed is all. No reference to any bleed process in the workshop manual. I'd just give it time to settle in, maybe manually turn the wheels to get some motion in there if you want to (I'd have it up on quickjacks, so that's easy enough to do). But if you want to run it around a bit and then lift it and recheck, that's a perfectly fine approach.

Got no idea on the 0B5 MTF process.

Thanks for confirming, seems easy enough.
I'll start with the rear diff first.

When I was replacing my wheel bearings I went underneath the car to check the rear diff and I'm positive that it's a standard rear diff as there was no ATF side
https://www.youtube.com/shorts/K6DLuL2VHuw

Thanks Smac as usual