RS5 S-Tronic fluid changes

A5/S5/RS5
#1

There is so much contradictory information out there I thought I’d hit this forum up and see if I could find a straight answer. I actually stumbled across AudiRevolution by accident.

There are two “parts” to the S-Tronic, one side takes ATF fluid the other, the mechanical side, takes gear oil.

Anyway, from my understanding, There’s a big service at 15K. I don’t know if it’s both sides or just the mechanical. The next service is at 35K and I believe this is just the mechanical side. The next is at 55K and it’s both?

I’m doing all the maintenance myself and several vendors sell “kits”. I’ve noticed that all of these kits are for the automatic side and not for the mechanical side. I’ve looked at ECS, Europarts, Blauparts, etc…but I never see a kit for the mechanical side. Wondering why that is?

Also, the differential. There are two fluids for the rear diff? Is one simply a friction modifier? There are a lot of gear oils that come with the modifier built-in so to speak. I believe this gets changed every 30K?

Thanks in advance and I hope I can add something to this forum in return!

#2

Welcome. AR is a great forum with lots of tech guys. The forum isn’t filled with tons of posts but with the technical guys on the boards your going to get first hand experience.

A few thoughts. depending on your end goals maybe try contacting JHM they have an in house RS5 that they bought eairler this year and knowing how they beat on there car they would have first hand experience on what they saw and what they found necessary. I know they are doing a bunch of performance mods to the car in house so that would also be something that might cross over and give you a few options as well.

IF you do reach out to them let us know what they say.

As to your question.

There are the two parts to your transmission.

The hydraulic side that takes ATF and the gear side or diff that takes gear fluid. So lets just call it the gear side.

According to Audi themselves and there maintenance schedule
DSG/S Tronic® – change MTF oil for gear box l RS 5 only = the first 15,000 then every 40,000
DSG/S Tronic – change ATF oil and replace transmission filter element
for clutch hydraulics RS 5, S6, R8 Coupe only = every 35,000

This is directly from Audi. knowing that the rev limit is so high it would make sense that you have to service this gear oil more frequent than other cars but from what I have seen these trnamissions have been plagued with issues so I would make sure to be ontop of the gear box oil changes. And there have been reports of issues for people who don’t change the filter at the 35k

So the answer is you don’t need to do both according to Audi. The mechanical side makes the most sense due to the higher RPM the transmission is running under and those conditions will break down the gear oil quickly.

#3

I’ve seen a “how to” on the gear side oil change and it’s quite easy. Given that it’s serviced more frequently, it’s surprising no one offers a kit with the correct fluid, number of liters and filter.

Yes, I’m well aware of JHM’s RS5! I’ve been waiting for updates rather impatiently as I want to see what they come up with. I already have a whole host of mods on the car and I’m prepping for any/all maintenance work and repairs if necessary. Battling installing ElsaWin as we speak. I’ve also downloaded all the Audi shop PDF’s off their site and I have a Vag-Com cable too.

So I should have had the auto side ATF and filter changed at the 35K service and the mechanical side at 15K and 30K. I’ll call the dealers that serviced the vehicle for the the big services. It has Audicare so I’m assuming they did the correct procedures for the transmission and differential.

Any idea on the differentials? Assuming there’s three? Front, mid and rear?

#4

Forgot to mention, I purchased the car originally owned by Shawn@Pacific German, a Misano 2013 RS5. Can see it here, just scroll through the gallery: http://klassenid.com/wheel-collection/monoblock/m10/#iLightbox[gallery-1]/16

Anyway, I’m absolutely in love with this car and want to keep it in the best shape possible.

#5

Welcome Ape! Agreed, it will be exciting to see if JHM will get their RS5 with stock internals on pump gas into the 10s! I think they will

#6

A good idea is to usually check the car fax. Audi updates car fax reports on service. So that should cover most of what Audi did if you can’t get anything strong from the dealer.

I would just check and make sure Audi did the fluid service. As not all dealerships seem to follow this even though its recommended.

There would be the rear end gear fluid in the rear axel. the front gear and diff in the front transmission.

#7

When you look at the 4.2 formula there isn’t anyone better than JHM. Since there supercharger head units had propelled several 4.2 motors in the 11’s and 10’s I don’t see why the RS5 would be different. Even the JHM RS4 tune was super close to the 11’s with just exhaust to help out.

Given what we have seen with the RS4, S4. S5 I think we will see a tested 2.75" exhaust a ECU tune that outperforms the rest by a good amount with a few added advancements that JHM always seems to find. Supporting parts like rotors that if you look they seem to have the rotors out already. and the proven and tested supercharger.

I think 10s is very likely

#8

The Carfax actually does list all of the services being done but doesn’t say exactly what obviously. I keep forgetting to call (busy at work) the dealer to check and see exactly what they did and if all the proper procedures were done. I’m sure they did do them but it’s a peace of mind thing.

Info from JHM can’t come fast enough. Luckily the car is pretty damn entertaining as is. Just loving it more every day. Can’t get enough of sending the tach needle to redline while accelerating. The sound is so damn intoxicating. Driving on the street is almost an exercise in frustration, LOL.

#9

Those are great cars.

Its a great idea to get all the documentation you can get. The more you know the better you can plan and this might be a for life car so its good to know every aspect of what the car has seen until you get it in your hands.

Its great to see JHM getting involved. The NA cars are a lot harder to make power on so you don’t see most companies put a lot of time into them as the amount of work that it requires to make good power is more intense and time consuming. The RS5 has always been an exciting car but lets face it more power can make it even more exciting as we all know.

If you look at JHMs home web page the RS5 takes center stage so it looks like this is going to be there current and possible future flag ship car. I don’t see this car not getting everything in the JHM arsenal thrown at it. For all of us 4.2 V8 lovers this is an excting time. For some of us more exciting than others espically if you have an RS5 https://jhmotorsports.com/

#10

[quote=“Ape_Factory,post:1,topic:9795”]
According to this document published by Audi (https://www.audiusa.com/content/dam/audiusa/Documents/maintenance-schedules/MY_2015_Audi_USA_Scheduled_Maintenance_9-7-2017.pdf),
the final drive gearbox on the RS5 trans should be serviced every 15/55/95/135 thousand miles.
The auto trans fluid is every 35/75/115 thousand miles.

#11

Just for reference, here are the official Audi part numbers for the transmission and rear differential fluids.

Gearbox
ATF: VAG G 052 529 A2
MTF: VAG G 055 532 A2

Rear Differential
MTF: VAG G 052 145 S2 Audi calls this axle oil but it’s a 75w-90 gear oil as near as I can tell.
ATF: VAG G 055 515 A2 This is a transfer case oil and goes on the ATF side of the differential.

I’ll be doing my rear diff and transmission in a few weeks. I’m going with an aftermarket ATF on the transmission side and I’m still researching the gear oil (MTF side) for both the transmission and differential but I’m leaning towards Motul 300 75W-90 which is GL4/5 approved.

There are a number of aftermarket fluids that meet the G 052 529 A2 specification and I’ve settled on Liqui-Moly 8100 DCT fluid.

For the ATF side of the rear differential, I’ll be sticking with the Audi-branded fluid which I’ve already purchased. It aint’ cheap, about $40, but you only need one.

#12

Check out redline.

They make some top line stuff. A lot of guys use that exclusively on the ZF transmissions and from personal experience it works very well.

#13

I’ve been doing a ton of research on fluids for the RS5 and it’s very hard to do any meaningful research without the OEM fluid specifications. The specs on Motul Gear 300 are really, really good but I can’t get a sense it’ll meet the needs of the mechanical side of the transmission (gears). I’ll be using Motul in the gear side of the differential.

The Redline MT90 is very close in spec but has a lower VI. Redline says it’ll work in the diff but doesn’t mention the transmission. I’ve found specs on a Polish VW site for the 055 532 spec but it doesn’t list A2. It’s a fairly narrow range viscosity and is thinner at operating temps than the Redline fluids by a smidge. But again, Redline doesn’t say it’ll meet that spec.

For the ATF side of the transmission, there are a ton of fluids that meet the 052 529 A2 spec but many of them, IMO, are too viscous at operating temp as they also meet the 055 532 spec which is for the gear side. Many DCT transmissions have a single chamber with all the mechanicals like the R35 GT-R. That means it has to meet the requirements of the hydraulic actuators, wet clutch AND gears. Audi divided it up. So the ATF handles the wet clutch (friction modifiers) the mechatronic hydraulics and cooling the electronics. The gear side does the gears and the front/center diffs (different friction modifiers).

No one makes a compatible fluid, except for Ravenol, for the rear differential ATF side. Motul’s Multi-DCTF meets both sides as, if I remember correctly, Amsoil’s DCT fluid does as well. Redline also makes a DCT fluid but it’s pretty viscous at operating temp like the Amsoil and the Motul DCTF. So I’m going with the Liqui-Moly 8100 for the ATF side, OEM fluid for the gear side. The rear diff will get OEM for the ATF side and Motul Gear 300 for the MTF side.

#14

Makes sense espically when you take into consideration the 8000rpm upper shift limits. I know lots of the B8 S4 guys did well with redline but again the extra rpm you should get the extra protection.

#15

I run redline, no issues ever

#16

The RS5 that I worked on did a lot better with Redline fluid and changing the small cooling filter.

#17

There were a couple of specs I didn’t like as much with the Redline fluid but it was my second choice. For the transmission I ended up with Liqui-Moly 8100 for the ATF side and the Audi OEM fluid for the gearbox side. On the rear diff, I did the OEM Audi fluid for the ATF side and Motul Gear 300 for the MTF side.

Someone else reported they spoke to Motul and said their Gear 300 (not the LS) would be fine for the MTF side of the gearbox. I just wasn’t sure how it’d play with the center differential.

I did the full swap, both fluids, for the transmission and the differential this weekend. Differential was pretty easy and the transmission was just time consuming, mostly because I was documenting everything along with shooting video and stills. Was fairly straightforward overall just a PITA on jack stands. I need a lift!

In the midst of doing a big writeup/full doc over on Audizine. I know the two forums don’t play nice but there’s a really large group (comparatively) of RS5 owners on there now and it’s active. I’ll try to cross post all the info here.

One advice, definitely do not let the rear diff service linger. I’d just go ahead and change both sides every 20K. The fluid looked like it needed it. I took samples and will be sending them out for analysis.

#18

Always great to see the updates thanks for popping in.

AZ is kinda a shithole so most tech guys who are anti drama came over here. A large group started to follow then AZ blocked all links to this site. The non trolls on AZ are cool as hell its just the drama and BS

Either way. We are all car guys over here its just enough traffic to enjoy and talk without all the background noise.

#19

Agreed, but honestly, we’ve kept most of the shit show at bay lately, especially with the RS5 community. There’s just so little information available on the RS5 that I think it keeps everyone united on a certain level. So we’re all behaving, even me, LOL. I definitely like the tech on this forum and I lurk in other section and live vicariously through other owners. But there is a larger group of owners “over there” and they tend to share their experiences, good and bad, and it helps enlarge the knowledge base.

But I definitely don’t have an issue cross posting on both forums. We all have reasons for selecting one over the other. I’ve only been around for a bit over a year so I missed much of the drama early on. Definitely not a newb to forums being a long, long, long time participant on the RX7 and Evo forums :slight_smile: So I’ve seen drama and then some.

Anyway, glad to be a part of this community and share my experiences here!

#20

It’s too bad this forum didn’t continue to grow at the rate it was years ago. I’m not sure why much of the activity has slowed? Saki? JHM?

Any idea Justin or Jimmy?

I was banned from the other heavily advertised main stream forum for calling out a stupid idiot, never gone back there since