Front differential service

[Nillious]

Could someone please verify the part number for the gear case/front diff oil for me? I want to change it and I’m not seeing any listed for the gear case and diff. I already did the dsg fluid but would like to do the gear oil as well. Everything I see listed is for the rear diff. I want to use Audi fluid. Thanks.

[doughboy17]

Sorry. You may want to call a trusted local Audi dealership and ask either a Service Writer or the parts desk for the part #.

[Smac770]

If it's the DL501-7Q DCT (type 0B5), there's two oils in it. The gearbox, center diff, and front diff are all in a common MTF oil system, same as the 0B2 and 0B4 6MT on which the 0B5 is generally based. Then the DCT ATF for the mechatronics and dual-clutch unit. item 3: https://audi.7zap.com/en/usa/audi+a4.../3/300-300055/

[Fresh.S4]

shopdap has the cheapest sport diff/ transfer fluid kits.


use this HF pump https://www.harborfreight.com/gear-o...ump-63588.html

[Nillious]

G055532A2 Is the number I kept coming up with. However when I go to order it fcp and ecs both tell me it does not fit my car. They both state this oil is only for the four cylinder A series cars. Fcp especially is usually pretty good about fitment so I was a little worried about using the wrong oil.

[SwankPeRFection]

G055532A2 is what’s listed in the full DIY for the center diff/gears portion of the DSG maint thread, which in my opinion SHOULD STILL BE STICKIED MODS!!!!

The reason it shows as incompatible on those sites is because they don’t want you putting that in your DSG’s mech section, which is what’s on the scheduled service list for the car. Does Audi even call for fluid change in the gearbox section? I can’t remember seeing it listed. I’m not saying not to change it, but be sure IT’S NOT GL5 rated oil. If it’s not made for the manual trans, it’s not made for a trans period.

FYI, that parts matching shit system that it seems ECS, FCP and everyone else has subscribed their site’s database to isn’t always right. ECS actually used to be more correct, but as of the last couple or so years, they too went with this new database everyone else is on.

[Nillious]

Ok thank you. So much conflicting information about this. In the thread below Smac posted a different oil than the one he just posted here. Just wanted to be sure and think I got it figured out.
https://www.audizine.com/forum/showt...2-or-G052911A2

[SwankPeRFection]

Well, now you’ve got me wondering too because it seems a newer part number is G052145S2, which is basically a 75w90 gear oil. It is GL4, so it should work. It’s possible when that original DSG DYI service was written by the original guy early on, the other stuff was all that was available. Now I’m not certain either. Lol

Supposedly the 911 one is GL5, which shouldn’t be good for brass synchros and anything brass, so now WTF because ECS shows it valid for a ton of cars, including ironically for SQ5, which isn’t DSG or manual. It also lists it for the B8S4 but I’m guessing due to the 6MT? But doesn’t that have brass synchros? See what I mean about what do you trust because you out the wrong stuff in, which can even happen at a dealership if they pull up wrong shit and you’ve got a fucked trans that was fine with old ass original fluid in there that’s never been changed until you changed it with wrong info.

[Nillious]

I had researched this in the past and found that B8 and B8.5 took different fluids due to them changing over to the crown gear. I can’t find that list now but it clearly stated a changeover build date for the different center differential. I’m gonna search around some more. I may call both dealers in this area and see if they give me different answers lol.

[doughboy17]

I may call both dealers in this area and see if they give me different answers lol.

Good choice. Frankly, it's a phone call. If you are aware of a couple of the most reputable dealerships in the country (I am unaware), you may want to simply call them to ask that question.

[SwankPeRFection]

The crown gear was introduced in 2013 for the B8.5 models. Prior years they didn’t have it. 2010 was first year without easily changeable coolant line filter. 2011/2012 got that and launch control (which was only a software change as I’ve got a 2011 with 2012 firmware on it and have launch control.) There may have been some other minor changes within those two years, but I can’t remember.

The Audi guy posted info based on a 2014 model year, so I’d be interested to know what will work in a B8 prior to the facelift based on Audi actual docs.

[SwankPeRFection]

* 2010 with 2011 software

[Smac770]

The 0B2 and the 0B5 use G 055 532 (include the RS 0B5), the 0B4 uses G 052 911. Per Audi. As I've already linked. Why? Who knows.
As for the G 052 513 MTF in the B8.0 0B5, who can say. But that is only a question for MY10/MY11 vehicles. MY12> are all G 055 532.
You don't mention your MY, so we can't directly address what might be relevant to your vehicle.

The crown diff was introduced with GP1 (the real first product improvement phase, the "facelift" for B8 was GP2) with the MY10 RS5 coupe and the MY10 A4 allroad, and moved to the Q5 also. But in the US market, the only presence of the crown diff is in the RS5 (MY13-MY15). The RS 0B5 uses the same fluids, but has a regular service interval for the MTF, unlike the A/S codes of the 0B5.

As others mention, don't count on applicability tables on a sales site. Even AoA's own parts.audiusa.com gets it wrong more often than we should hope.

[SwankPeRFection]

The 0B2 and the 0B5 use G 055 532 (include the RS 0B5), the 0B4 uses G 052 911. Per Audi. As I've already linked. Why? Who knows.
As for the G 052 513 MTF in the B8.0 0B5, who can say. But that is only a question for MY10/MY11 vehicles. MY12> are all G 055 532.
You don't mention your MY, so we can't directly address what might be relevant to your vehicle.

The crown diff was introduced with GP1 (the real first product improvement phase, the "facelift" for B8 was GP2) with the MY10 RS5 coupe and the MY10 A4 allroad, and moved to the Q5 also. But in the US market, the only presence of the crown diff is in the RS5 (MY13-MY15). The RS 0B5 uses the same fluids, but has a regular service interval for the MTF, unlike the A/S codes of the 0B5.

As others mention, don't count on applicability tables on a sales site. Even AoA's own parts.audiusa.com gets it wrong more often than we should hope.

Can you dumb down all the gibberish into meaningful info for model years please?

What year have what boxes and what fluid do they take? Would make it easier for everyone to understand. Thanks

[SwankPeRFection]

Also, why are you saying the B8.5 13+ S4 doesn’t have the crown gear? There is/was Audi docs that stated those cars got it. Where is your info coming from because there’s conflicting info somewhere.

[Smac770]

As the gibberish says, G 055 532 for MY12+, G 052 513 for MY11, one or the other for MY10 depending on the trans code.

[jessenepywoda]

When I took out the drain plug, i got maybe 1/2 qt of gear oil out of mine. MY12, 145k miles. Filled it and, needless to say, it is working way better. I don't know how it got like that with no visible leaks.... But my point is everybody should check/change this fluid.

[Corydms7]

Center diff is 75W-90 GL-4 or the gear oil for the trans. I used Redline 75W-90 like 5k miles ago. Works perfect. Rear diff is 75W-90 GL-5 fluid. For this I just went on shopdap.com and searched B8 S4 sport diff service kit. It comes with the gear oil and the transfer case oil (if you have a sport diff)

[carguy19]

Could someone please verify the part number for the gear case/front diff oil for me? I want to change it and I’m not seeing any listed for the gear case and diff. I already did the dsg fluid but would like to do the gear oil as well. Everything I see listed is for the rear diff. I want to use Audi fluid. Thanks.

How many miles are on your car?

If you have higher miles, you're better off not changing the fluid in the diff, just top it off. Audi dealers don't recommend full fluid changes at any mileage, only level inspection and checking for leaks.

New fluid, although an oil, can cause more issues then do good when tolerances are tight and clutches abundant.

I would just top it off if I were you.

[Nillious]

The only case where this situation is sometimes true is with automatic transmissions. If the fluid is badly broken down and has a lot of debris in it new fluid can cause slippage to an already damaged transmission. New gear oil of the correct specifications in a gearbox is never a bad thing. Lots of people have serviced their manual transmission’s with no ill effects as long as the correct fluid is used. This part of the transmission is a basically no different than a normal manual. transmission.

As was stated earlier many people put in a gl5 gear oil and that absolutely can cause problems.

[Smac770]

Also, why are you saying the B8.5 13+ S4 doesn’t have the crown gear? There is/was Audi docs that stated those cars got it. Where is your info coming from because there’s conflicting info somewhere.

Missed you had asked this. Here's the gibberish answer: https://www.audizine.com/forum/showt...1#post14253578
The short answer, because only 0B5... p/n center diffs are crown center diffs, and they were only used in specific type 0B5 transmission codes, for the RS, the Q5, and the allroad.

[SwankPeRFection]

MKX MNL What year and what’s in it?

[wrxkyle]

I had researched this in the past and found that B8 and B8.5 took different fluids due to them changing over to the crown gear. I can’t find that list now but it clearly stated a changeover build date for the different center differential. I’m gonna search around some more. I may call both dealers in this area and see if they give me different answers lol.

evidently the b8.5 does not in fact have a crown gear and that's the rs models. it would also only be late model 2013's as the early model 13's still had the 1.5 (much to my disappointment not realizing that before i bought mine with the 1.5...

and keep in mind the 0b5 (dual clutch) in the rs5 is otherwise the same as in the s4, but the rs5 does have the crown gear, and because of that they do have a service interval of 40k miles for the Manual transmission fluid in the gearbox of their dual clutch autos.

i would extrapolate that out to say it's not a bad idea to change yours every 40-60k miles esp if you drive hard. crown gear differentials have friction plates that wear, heavy amounts of slip causes those to wear more like what you would expect in a performance car like the rs5 that has a lot of hp. the same diff used in the q5 suv and the allroad they expect to get MUCH less and much lighter use so they just keep on with the "eh, lifetime fill will get us by till it's not audi's issue anymore" mantra. i imagine if the s4's got that diff then they'd be calling for that interval.

[wrxkyle]

How many miles are on your car?

If you have higher miles, you're better off not changing the fluid in the diff, just top it off. Audi dealers don't recommend full fluid changes at any mileage, only level inspection and checking for leaks.

New fluid, although an oil, can cause more issues then do good when tolerances are tight and clutches abundant.

I would just top it off if I were you.

this is not great advice, audi dealers call it a "lifetime" fluid, NO FLUID is a lifetime fluid. what audi means by that is "this fluid will last as long as your warranty and or most of our first owners will keep the car" failing after that period is a feature, not a bug. planned obsolescence. just like the rear diff oil is lifetime fill, or the sc oil is lifetime fill. it's a "it lasts long enough that it's not OUR problem" kind of thing. whether it becomes YOUR problem is a totally different issue. thankfully it is cheap and easy to change out.

@op i blew up my rear diff, not sure if it was abuse from previous owner or wheel hop launching in damp/wet conditions but i damaged some gears and it was whining really bad and creating a metal slurry so i replaced it with another used unit, fluid had never been changed and was very dark and nasty, and that's not even a limited slip diff that would get dirty from clutches wearing. in the new diff given it is an open diff i had them fill with motul gear 300, and did motul gear 300 in the gearbox section of the dsg as well and is has been great with no issues.


you're welcome to use the audi oil as well if you prefer.

WHAT YOU DO NEED TO BE CAREFUL ABOUT is you need a non corrosive gear oil, there's corrosivity tests on copper for some of the gear oils over time and with heat that is exacerbated, i want to say mt90 was least corrosive but i don't remember so look it up, gear300 was not concerning either.

WHY IS THIS IMPORTANT? you have a sensor, the gear position sensor, that is known to sometimes fail already on this platform, and replacing it is like 2k, mostly labor plus the $400 sensor assembly. that sensor has copper traces and wires, so while we don't need to worry about corrosivity in the traditional context of "being safe for yellow metals" (ie brass synchro's) we still want to make sure we use the least corrosive gear oil possible to protect that sensor as much as possible.

[Smac770]

MKX MNL What year and what’s in it?

MKX is the code for the rear differential, not the transmission.

MNL is a flange shaft 0B5 for the 3.0T, so has to be B8.0 MY10. B8.0 MY11/MY12 would be stub shaft versions, MSE and NGY. With the original shorter B8.0 gear ratios for 2-7. same first gear ratio. The R&R part for the center diff on the stub shaft 0B5 was 0B2 409 755 H, which is a Torsen center diff, not an 0B5... crown center diff.

Now had it been a stub shaft MSE with a build date prior to Oct '10, the catalog implies the R&R part for the center diff is 0B5 409 755 K. And 0B2 409 755 K starting with Oct '10. Is that a documentation oversight, or were there several months of production of S4/S5 0B5 with a crown diff? No one has shown evidence of that specific scenario in either direction yet, iirc.

[SwankPeRFection]

It literally says Engine Code / Trans code and has CCBA for the engine and then those two other codes afterwards. So…. ?

[SwankPeRFection]

Build date is 5/10.

[Smac770]

But what is the VIN year code? A or B? May '10 is right on the border of the MY10 to MY11 production switch. MY10 used flange shaft transmission output; MY11 used stub shaft transmission output. MNL is flange, MSE is stub. So with an MNL transmission code, I'd expect your VIN year to be A.

Yeah, the way they label the sticker, ... But it's engine code to the left, then diff code / trans code to the right:
CCBA - B8.0 3.0T engine for US emissions
MKX - B8.0 type 0BF sport rear diff with 35/9 ratio
MNL - B8.0 type 0B5 aka DL501-7Q DCT for 3.0T engine with flange shaft connection

The one exception to this MY11 stub shaft intro seems to be the MY10 RS5 intro, which appears to have been stub shaft from the get go. Contrast that with the other MY10 GP1 introduction, the A4 allroad. Which used 0B5 flange shaft for MY10 and then switched, with everything else to stub for MY11. So the 0B5 center diff was always used only with stub shaft output variants.

[SwankPeRFection]

OK, you lost me because you say above that “MNL - B8.0 type 0B5” w/flange. Then in the last sentence you say “So the 0B5 center diff was always used only with stub shaft output variants.” so… which is it? Maybe I’m just slow…

[Smac770]

OK, you lost me because you say above that “MNL - B8.0 type 0B5” w/flange. Then in the last sentence you say “So the 0B5 center diff was always used only with stub shaft output variants.” so… which is it? Maybe I’m just slow…

What are you presuming there? Your two quotes of my text are not conflicting statements. So...both.

[SwankPeRFection]

Well, you’ve said no S4 ever came with a crown diff, which was only in 0B5 trans. So here we have an early 2010 S4 with 0B5 trans. Are you saying all crown gear having trans have to be 0B5 code but not all 0B5 could be crown gear? I’ve read through some of the other thread I found where someone else started and you pitched in with info, but some of it was still not clear.

Considering that center diff would require more maintenance in terms of gear fluid changes and since Audi mentions nothing about the gear side on S4’s, why put such a maintenance sensitive center diff on something like a Q5 and AllRoad when those are even more average consumer/more mileage utilitarian use than an S4 would be. Made sense on the more sporty RS5, but not those others, especially since you’re adamant they never put them in the S4. Or did I misread/misunderstand something?

[Smac770]

You need to separate the type designation of "0B5" from the parts bin designation of "0B5".

So take the B8 A4, aka "type 8K". Lot of parts on the car will be 8K0 xyy zzz, aka parts bin 8K0, group x, page yy, item zzz. For a vehicle type, which is only two characters, the third character usually has some general meaning. 8K0 is general, 8K1 is LHD specific, 8K2 is RHD specific, 8K5 is sedan specific, 8K9 is wagon specific, etc. And there's always exceptions to the concept, particularly in the infotainment units. But an 8K vehicle will also have a lot of 8T0... parts and 8R0... parts, even 4F0... parts (the B8.0 steering wheel buttons, e.g.) or 4L0... parts (the B8.5 steering wheel buttons). 8T = B8 A5, 8R = B8 Q5, 4F = C6 A6, 4L = Mk1 Q7, etc. Even the type 4H (D4 A8) uses an 8K0... wheel hub.

So the "type 0B5" transmission is the type code for the otherwise known as DL501-7 DCT transmission. DL501-7Q being the variant with integrated quattro. But the DL501 is basically a dual clutch conversion of the 6MT transmissions. That's why the housing is an 0B2... part number. And for nearly all of them, the center diff is an 0B2... part number.

Where the center diff is an actual 0B5... part number (0B5 409 755), that will be a crown gear center diff. Where the center diff is an actual 0B2... or 0B4... or 0B6... or 0BK... or 0BL... part number, it's a Torsen center diff. Only the type 0B6 (ZF 6HP28AF) used the 0B6... center diff. Only the type 0BK (ZF 8HP45A) and type 0BL (ZF 8HP90A) used the 0BK... and 0BL... center diffs, not aligned by type code but by whichever Audi put in each particular trans code. And only the type 0B5 (DL501-7Q) used the 0B5... crown gear center diff. But the type 0B5 did not only use the 0B5... crown gear center diff. Most used an 0B2... Torsen center diff. The type 0B2/type 0B4 6MT used 0B2... and 0B4... center diffs, again, similar to how the 0BK/0BL intermingle. But in the end, 0B2... seemed to dominate.

So the type designations and the parts bin are related, but not exclusive usage to each other.

[Smac770]

As for why did they put 0B5... center diffs in the type 0B5 for those particular non-RS applications? Hell, no idea. Can only speculate the business side of things that always turn clean logical engineering into a logistical mess.

[SwankPeRFection]

So what you’re saying is, if someone needed to rebuild one of these transmissions, they’d have no option but to open it first and see what specific parts they need short of preordering. Granted, that’s usually how things are done, but let’s just speculate you’ve not a messed up center diff… no way to know from VIN or trunk label codes short of actually opening the damn thing and looking at the part number stamped on the housing of the diff? Is that a correct assessment? Because if so, then that’s stupid. Makes you wonder how badly some of these parts sellers online and even some dealerships can be with getting you the correct part for your specific car. Seems like a rats nest of part numbers that could have the possibility of being totally off sometimes.

[Smac770]

I expect the center diff in a type 0B5 code MNL is exactly what the parts catalog pages say it is, 0B2 409 755 H, which is a Torsen 3 planet gear second gen PAT 40:60 Torsen diff, not a crown gear diff. Now, could you retrofit enough parts to swap that 0B2... center diff out for an 0B5 crown gear center diff? I imagine you could, if you really wanted to. But you'd also need to swap the trans output form to spline, meaning swapping the cardan shaft (drive shaft) also.

A dealership is just going to throw your VIN in and get whatever it gets back. I prefer to understand all the possibilities, not just "this is the X that goes in VIN whatever". Because I'm not a shop on the clock looking at this stuff. I'm just curious about it. So it might seem a cluster f to someone who's not parsed through it before, but it is defined and accurate for its purpose. Those seeking an understanding beyond simply "what X goes in my VIN" have to invest effort to boil the basic information into something structured. That's why that link of mine is 10 slides of info I pieced together to get an informative viewpoint on the center diff evolution.

The only chance an S4 or S5 has of somehow having gotten an 0B5... crown gear center diff in their type 0B5 DCT transmission according to the parts catalog is if it's an MY11 code MSE built before Oct '10. Opening one of those would be interesting. Otherwise, it's pretty much set what's in what. Unfortunately, 7zap has moved their stuff pretty much behind a pay wall, and ilcats seems pretty unstable these days.

You can look over some of the info about the crown diff and MTF temp monitoring and such in SSP 617. It's dated Oct '12, so with the release of the MY13 RS4, three years after the RS5 already introduced in MY10.

[SwankPeRFection]

Thanks for the explanation. It’s been an interesting read.

[Ai_barber_guy]

I have a 2010 dsg mnl. What goes in the manual area? I'm so confused. Go55532a2?

[Smac770]

If you have a DSG, you have a VW, so no idea. If you have a B8 with s-tronic, ie an Audi DCT, then the MTF is G 052 513 A2 for through MY11, and G 055 532 A2 for MY12 onward. Except, it appears, if you have an MY10 A4/S4 with a NVZ (3.0 TDI), NWD (2.0T), or NWF (3.0T).

https://www.ilcats.ru/audi/?function...61&language=en

What's curious, is this mixing of info for the MY10 year is listed only for the A4/S4 catalog. Not the A4AR catalog, not the Q5 catalog, not the A5/S5 catalog, not the RS5 catalog. And only those three codes, not those codes and those that came after (Pxx, Qxx). Good luck ever getting any clarity from Audi on what that whole thing is actually about.

But for an MNL, the page clearly says what MTF goes in it.

[Ai_barber_guy]

If you have a DSG, you have a VW, so no idea. If you have a B8 with s-tronic, ie an Audi DCT, then the MTF is G 052 513 A2 for through MY11, and G 055 532 A2 for MY12 onward. Except, it appears, if you have an MY10 A4/S4 with a NVZ (3.0 TDI), NWD (2.0T), or NWF (3.0T).

https://www.ilcats.ru/audi/?function...61&language=en

What's curious, is this mixing of info for the MY10 year is listed only for the A4/S4 catalog. Not the A4AR catalog, not the Q5 catalog, not the A5/S5 catalog, not the RS5 catalog. And only those three codes, not those codes and those that came after (Pxx, Qxx). Good luck ever getting any clarity from Audi on what that whole thing is actually about.

But for an MNL, the page clearly says what MTF goes in it.

Thanks, Dang I got g055532 for the mnl. After researching It seems the differences is 532 is 70w80 whereas the 513 is 70w90. No info on what's gl4 or gl5 rated. Idk if you have any further info on that. I'm hoping it doesn't crap out the transmission. That's a hefty hope 😬 All I know is what came out was thin and had a distinct smell. Given the 100k miles on it I'm sure it's changed from its original state. At first we got the 513 but the mechanic said it's clearly different even with the age of what came out. So I ordered the 532.

[Smac770]

Beyond the parts catalog, I don't have any info to explain the 513 to 532 change. Lower weight, is it Audi just chasing some mpg? Or was the 513 weight just heavier than necessary? Was there any other internal component change that accompanied the fluid change?

0B1 6MT FWD, 350Nm limit
<200hp engine: G 052 532

0B2 6MT quattro, 350Nm limit
<200hp engine: G 052 532
>200hp engine: G 055 532

0B3 6MT FWD, 400Nm limit
G 052 911

0B4 6MT quattro, 500Nm limit
G 052 911

0B5 DCT quattro, 550Nm limit
>MY11, G 052 513
MY12>, G 055 532

Maybe they were expecting to need a heavier MTF with the even higher than 0B4 torque handling? And then figured "yeah, we don't really need that"?

As to "will it really matter if I put 532 in my MY10"? I can't guarantee anything. If it were a 6MT, probably not an issue. But since the mechatronic is doing the shifting, was it's programming adapted for the MTF change? Someone who's actually run (G 055) 532 in an MNL would have to comment on their experience.