I am planning on changing my manual tranny oil and my rear diff oil right away here, and am looking for some feedback on the different brands out there. First off, I am aware that the manual tranny gets gl4 spec 75w90 gear oil, and I am pretty sure that the rear differential takes gl5 spec 75w90.
Now, I have read a LOT of info on the various brands, but most of it is not specific to audi/vw trannies. Anyone out there have anything positive or negative to say about some of them? Notables may be mobil 1 75w90, castrol syntec 75w90, amsoil, redline mt90, motul 300, oem, and the list goes on. Btw, I am certainly not opposed to using oem, and if you have experience comparing oem to some of these oils, please post up your experiences!
At this point, I feel that I am leaning towards using redline, but am also curious about amsoil and perhaps oem.

 

Make sure to check these out: ATF Change On Audi A4, A6 and A8 (Auto Trans!) with photos! and A4 Rear Differential Oil Change DIY (with pics!)

As far as ATF brands goes, I'm sure everyone will have his/her own opinion(s) based on personal experience, brand loyalty, price, availability, performance, etc. It all boils down to what it is you expect to gain in the end. I say stick to OEM but I'm sure someone else will tell you otherwise. Good luck!

 

thanks for the link Mona, however, as stated in the thread title, i am changing manual transmission oil, not automatic transmission fluid. two very different things lol
btw, in case anyone needs a DIY, here are a couple:

Audi area: Audi B5. B5 5 spd tranny fluid change

AudiWorld Tech Articles

the other thing is, that unlike engine oil, when it comes to manual gearbox oil, there can be a drastic difference from one oil to the next, and it is very noticeable, as you feel how the car shifts (unlike the possible 1-5hp difference between some engine oils which you may or may not feel on the old "butt dyno")
also, different gearbox oils respond quite differently in different climates and temperatures. so in this case, i think that the brand merits discussion. i know, for example, that many people mix 1/3 redline MTL with 2/3 redline MT-90, and going by the numbers, this should give a similar viscosity to Amsoil MTG according to the following link:

Been doing some gear oil comparisons for 6sp Audi - Bob Is The Oil Guy

i have also read that some people did not like the feel of the shift with amsoil, but others did. i happen to be a big fan of amsoil engine oil, but have no experience with their gear oil. redline seems to be about the most popular, but motul is also used a lot. I happen to live in a pretty harsh winter climate, so i am very interested in peoples experience with cold shifting as well.

 

Good catch! I was actually just in the middle of posting that same 5 speed ATF change in the DIY section.

EDIT: Fixed! HERE is the A4 Changing the Transmission Gear Oil (5Speed!) with pics thread!

 

WTF, I just posted something like this and it didn't take. Let's try this again.

My take on fluids is unless you can show that it does something better than OE fluids then there is no point in changing. Gear oils certainly fall into this category because they are not all created equal nor do they work the same. There are different specifications and you must make sure you are using the correct one, if the car calls for GL-4 then you have to use it and if it calls for GL-5 then you have to use that. You can't switch specs because they are formulated differently and some transmissions/diffs react really badly to the wrong fluid. You must make sure the fluid is all synthetic (I read somewhere that gear oil is one of the few oils that was actually 100% synthetic whereas engine oils are still based off of dyno oil) and have the weight 75W/90.

According to ELSA the gear oil and transmission oil on these cars should be the factory part number 'G 052 145 S2' but my version is pretty old so this may have been superseded since publishing. This means both take the same fluid and this includes the diff on the auto transmission. Unless you are pulling a horse trailer or racing the car you really have nothing to lose by running the factory fluid but you have a lot to lose by running the wrong stuff. Read any 'what oil should I put in my car' thread and you will know what I mean because there are so many people that are way out there and spout with no knowledge.

I always recommend looking around locally and find that shop that sells all of the OEM stuff but not at the dealer prices. Buying a $12 injector o-ring from the dealer doesn't make a lot of sense when you can buy the same one from a wholesaler for less than $2. I buy all of my OE parts locally from a place called VM Autohaus which is in the Lower Mainland so you should find a parts place like this locally as well. Put nothing but OEM or OEM quality parts in your car and you can't go wrong.

 

Well, I can not find any fault in your logic, and you definitely make a good case for oem. As I stated, I am in no way opposed to using oem, either.... Just curious if anyone has used a non oem fluid and found an improvement - especially in cold shifting, as I live in a pretty cold region here, with probably an average of 30-40 days per year colder than -30.
Thanks for your input, corrado guy..... Anyone else want to chime in?

 

I have tried different fluids in my Corrado and they were either worse or they felt no different so I didn't see the point in changing things. I have either OEM or Royal Purple in the Corrado right now and I could find no difference. When I changed the fluids in the Syncro I just went with the factory fluids and I will do the same for the Audi.

Keep in mind when it is colder out you generally allow the engine to warm up a bit but your drive line is still cold so you have to warm this up as well. In the cold I always double-clutch and this makes a world of difference because it allows the sluggish internals of the transmission to catch up. A simple procedure, you start 1st gear and when you go for 2nd you put in the clutch and put the car in neutral and let the clutch out and put the clutch back in and rev match it and into 2nd and let the clutch back out. It takes a while to get it down-pat but my Corrado has had a crunchy second gear in the cold since I bought it and 8 years later it still feels the same with no degradation with the use of double-clutching when cold. You can do this or do really slow shifts and let the transmission pull the gear in instead of you forcing it. Rev matching is really important because it allows the hub & slider to match speeds and this will literally pull the car into gear if you have right. If you have ever done any clutch-less shifting you will know exactly what I mean when I say the transmission will pull itself into gear, like a hot knife through butter.

 

i have the current part numbers here for ya corrado guy....
just got home from my local dealership (which i have always found to actually have a very low mark up on parts) and here are the results:

Manual Transmission Oil
Part # G 052 911 A2 (this part number appears to be different)
Cost: $30.19/L
Requires 3 bottles

Differential Oil
Part # G 052 145 S2 (this is the part number you had listed)
Cost: $35.38/L
Requires 2 bottles

Also checked with the one and only redline dealer in my city, and he is charging $18/L for MT-90 and same price for MTL

i opted to go for the oem fluid, and will likely do the swap next weekend or the weekend after. it wasn't cheap, but i had never said that price was my major concern. I feel that using price as a deciding factor for parts for these cars is a highway to hell. i always look at quality and performance first, THEN try to find my best price within those parameters
after the change i will update this thread with my subjective (as always) impressions.

 

I wonder what the difference is, the factory repair manual lists the second part number for both the transmission and rear diff. I don't have access to service bulletins so there must have been a revision in there somewhere from the time the manual was last updated and now.

 

Not sure what the difference is (besides cost), but I am guessing the diff oil is gl5 and the tranny oil is gl4, but I have no way of knowing for sure. If I remember, I will take a closer look at the bottles tomorrow and see if there is any other difference listed other than part number.