VW/Audi G-052-145-S2

[The Critic]

VW/Audi specs this product for rear differentials and transfer cases. Supposedly it is a 75W90, but Redline recommends their MT-90 product, not their regular 75W90. Their rationale is that Audi uses a "low offset rear final driver gear set" and this setup does not require GL-5.

It seems unusual to run a GL-4 rated fluid in a diff or transfer case. I have been unable to locate any info on the factory fluid.

Does anyone have more info on this peculiar application?

 

[UG_Passat]

Could be worse, it could be using 75w GL-4 oil.

I have used Amsoil SS 75w90 in the transfer case and rear differential (bevel box) on my Tiguan 4Motion without issue.

 

[benjy]

i use-d the MT90 VW + Audi tranny with transverse engine with repeat success + 75-90 gear lubes in other differentials. Call Redline for better info + explanation. years ago i used a recommended series 2000 amsoil tranny lube that caused issues in my 2001 O2J 5 spd jetta, Amsoil had NO reply!!

 

[UG_Passat]

i use-d the MT90 VW + Audi tranny with transverse engine with repeat success + 75-90 gear lubes in other differentials. Call Redline for better info + explanation. years ago i used a recommended series 2000 amsoil tranny lube that caused issues in my 2001 O2J 5 spd jetta, Amsoil had NO reply!!

I used Amsoil MTG on my 02 Golf TDI 02J without issues.

Maybe the series 2000 was a GL-5 lube and you were using it in a GL-4 application?

 

[Timmastertech]

I use the VW oil. My cost is 22 bucks a liter. There isnt enough cost savings on the oil going with redline or motul to make it worth risking a box

 

[The Critic]

VW/Audi specs this product for rear differentials and transfer cases. Supposedly it is a 75W90, but Redline recommends their MT-90 product, not their regular 75W90. Their rationale is that Audi uses a "low offset rear final driver gear set" and this setup does not require GL-5.

It seems unusual to run a GL-4 rated fluid in a diff or transfer case. I have been unable to locate any info on the factory fluid.

Does anyone have more info on this peculiar application?

I wonder if VW G-052-145-S2 (previously G-052-145-A2) is just Castrol SAF-XO. There is some speculation here:

Revised formula OEM differential oil coming

Old OEM gear oil for our rear differentials was Castrol SAF-XO: Viscosity index = 160 Kinematic viscosity @ 40C = 100.0 Kinematic viscosity @ 100C = 15.2 Newly revised product is called Syntrax Longlife: Viscosity index = 162 Kinematic viscosity @ 40C = 103.7

www.audizine.com

Differential fluids - AudiWorld Forums

A8 / S8 (D3 Platform) Discussion - Differential fluids - So, since I'm going to be doing my ATF next week, I figure while I'm there, it wouldn't be the worst idea to do the diffs as well. From what I can find, Audi says the center and rear diffs need their whatever fluid with FM modifier, while...

www.audiworld.com

If so, an dual-rated 75W90 should work.

 

[Wheel366]

I don't know which model Audi you have but do NOT use MT-90 in your trans. I can't speak for transfer case or rear diff. I used Amsoil for all my diffs and transfer case in my Audis with no problems. I used a GL4 for my S4 and an GL5 for my A4.

 

[The Critic]

I went with Motul Gear 300 75W-90 in the Bevel Gear and Rear Differential. It is supposedly "dual-rated" for GL-4/GL-5. I don't think either of these components contain parts that are susceptible to damage by GL-5, so it should be fine.

 

[930.engineering]

I wonder if VW G-052-145-S2 (previously G-052-145-A2) is just Castrol SAF-XO.

G 052 145 is G 052 145. The 'S2' and 'A2' just indicates the size of the container.
'A2' means one litre bottle.

I can't speak for Audis with longitudinal engines and transmissions but I'd strictly
avoid dual rated gear oils in VWs and Audis with transverse mounted engines and
transmissions. These cars are happiest with straight GL-4, ideally a 75W or 75W-80.
.

 

[The Critic]

G 052 145 is G 052 145. The 'S2' and 'A2' just indicates the size of the container.
'A2' means one litre bottle.

I can't speak for Audis with longitudinal engines and transmissions but I'd strictly
avoid dual rated gear oils in VWs and Audis with transverse mounted engines and
transmissions. These cars are happiest with straight GL-4, ideally a 75W or 75W-80.
.

Got it. This is a transverse application with a DSG. The oil was for the bevel gear (attached to the DSG) and the rear differential.

 

[randomhero439]

I’d either run the factory fluid, or a GL-5 oil. Also remember too the differential gears see extreme pressures and may need a GL-5 unless they performed acceptably for the validated factory fluid.

Unless this is for a transaxle. The GL-4 because of the Syncro material

 

[brianl703]

Unless this is for a transaxle. The GL-4 because of the Syncro material

And don't need GL-5 because transaxles do not use hypoid gears in their differentials.

Theoretically, a rear differential that didn't use hypoid gears wouldn't need GL-5 either. It would be fine with GL-4. The whole reason for using hypoid gears is to lower the driveshaft in relation to the centerline of the differential, so the driveshaft tunnel can be lower.

Or so I've read.

 

[930.engineering]

.
Yes, of course. However as I understand it he still talked about the 'bevel gear
attached to the DSG' and if it has its own oil fill it's probably (also) happy with
GL-5. You'll likely know the bevel gear turns power flow by 90° just like the rear
diff. Sadly product data sheets rarely talk specifically about these applications.
.

 

[brianl703]

.
Yes, of course. However as I understand it he still talked about the 'bevel gear
attached to the DSG' and if it has its own oil fill it's probably (also) happy with
GL-5. You'll likely know the bevel gear turns power flow by 90° just like the rear
diff. Sadly product data sheets rarely talk specifically about these applications.
.

Far as I know, the only reason to avoid using GL-5 is if there are yellow metals or synchronizers in the application.

 

[930.engineering]

.
I tend to agree on that though I'm open to hear other opinions.
.