MTF (Manual Transmission Fluid) Change Interval and Replacement

[1000whp]

Hi everyone! I have asked about manual transmission fluid change in another thread and know that Motul Gear 300 (75W90) is a good candidate. My B7 S4 now has 41k miles and I plan on doing this @ 45k miles.

• What is the ideal change interval (every 40k?)
• Is 75W90 the right viscosity?
• How many liters I do I need each time? Assuming I am doing transmission and differentials at the same time.

Thanks in advance!

[dparm]

The factory change interval is 45k I believe. I change mine yearly because I track and autocross the car. I consider it cheap insurance. The average driver can probably do it every 2 years.

You need 75w90 with a GL-4 rating. It's 3.5 quarts.


The rear diff is 2qt. I buy the Gear 300 by the case.

[1000whp]

Thanks! So every time I do tranny + diff I will need 5.5 quarts?

Where is the best place to buy Gear 300?

[dparm]

Yes. I call it 6 just to be safe. Yours may take a little more or a little less. The MTF should get changed more frequently than the rear diff (perhaps twice or three times as often).

Local tuners/speed shops usually stock the stuff or can order it. Otherwise ECS carries it; contact them to get a quote for a case, you can save a little bit.

[1000whp]

Gotcha. Thanks so much for the info! I probably won't be able to find it @ autozone right?

[dparm]

Definitely not.

[Silver B6 S4]

The factory change interval is 45k I believe. I change mine yearly because I track and autocross the car. I consider it cheap insurance. The average driver can probably do it every 2 years.

You need 75w90 with a GL-4 rating. It's 3.5 quarts.





The rear diff is 2qt. I buy the Gear 300 by the case.

There is no change interval for the trans/difs. It is a life time fluid according to Audi, which is bullshit.

http://www.euro addiction.net/forum/showthread.php?t=654

^ Delete the space between o and a.

[1000whp]

There is no change interval for the trans/difs. It is a life time fluid according to Audi, which is bullshit.

http://www.euro addiction.net/forum/showthread.php?t=654

^ Delete the space between o and a.

What did it say?.... It won't let me view it unless I am a member

[road race s4]

I got my Motul Gear 300 from Amazon. They had a deal for like $12 a bottle several months ago and I jumped on it.

[Mi1lion]

I THINK mine was changed at the 45k mile service, if that's part of the service. I have personally never changed it and I have 155k on the clock. I was also told that sometimes it's just better to leave it, because of misc reasons. Anyone car to tell me why they would suggest this? Thickness? Deposits? Lube Issues? Or is it really a lifetime fluid...

[dparm]

There's no reason to "leave it". Replace that shit if you want the tranny and diff to be in good health.

Even if I am being overly-cautious with frequent replacements, I'd rather drop $50 on fluid than $2000 on a trans.

[Mi1lion]

^^^ Could'nt agree more, as I thought this was smarter, but apparently some people think not. So I'll buy the Motul Gear 300 for both Tranny/Rear Diff.. Is this right?

[dparm]

Yes sir. Been running that for a year of city driving, highway driving, autocross, track days, and even ice racing. Check my article if you want to save some dough or don't need an extreme-use fluid.

Perhaps you could find a local member and split a case of the stuff.

[P0234]

There is no change interval for the trans/difs. It is a life time fluid according to Audi, which is bullshit.

See, that's where you are totally wrong, it IS a lifetime fluid! Lifetime of the warrantly... not the car! LOL.

[noznab]

I got my Motul Gear 300 from Amazon. They had a deal for like $12 a bottle several months ago and I jumped on it.

Wow thats a great deal! I couldn't find it cheaper than 18 or 19 a bottle. After reading the MTF thread I settled for lubro moly, I don't track my car that often anyway

[WinterRunner]

Lobro-moly is always good stuff.

[zachf88]

I use Liqui-moly GL4+ with MoS2 additive. It's as smooth as butter, even in the extreme cold!

[b spot]

Probably a dumb quesiton since I can't find a DIY, but how do I change the transmission fluid? Where do I drain it from and do I need anything besides the fluid?

[Mr. Corey]

See, that's where you are totally wrong, it IS a lifetime fluid! Lifetime of the warrantly... not the car! LOL.

My dealer told me that too hahaha

[dparm]

I'm baffled that Audi would call it lifetime on a performance car they know gets beat on regularly. For a more ho-hum A4 with an auto trans, it can probably go a long-ass time before needing a change.

[audi49]

Probably a dumb quesiton since I can't find a DIY, but how do I change the transmission fluid? Where do I drain it from and do I need anything besides the fluid?

So is this a fairly easy DIY?

[1000whp]

I'm baffled that Audi would call it lifetime on a performance car they know gets beat on regularly. For a more ho-hum A4 with an auto trans, it can probably go a long-ass time before needing a change.

I thought ATF needs to be replaced very often because AT generates a lot more heat than MT?...

[halik]

See, that's where you are totally wrong, it IS a lifetime fluid! Lifetime of the warrantly... not the car! LOL.

Lifetime fluid, just change the trans every 100K... :)

[dparm]

So is this a fairly easy DIY?

It's no different than any other manual transmission. Drain it, and fill it.

[b spot]

Where do I drain it? :)

[dparm]

I don't recall, but if you get under there you'll see the big bolt. It's the same kind of bolt as the oil pan.

[B6JoeS4]

I too run gear 300 in the trans and the diff. I will be changing it every year

[Jengel451]

Before you drain either one, make sure you can open the fill plug, nothing worse than doing it the other way around and finding out the fill is stuck for whatever reason.

[b spot]

Thanks guys! Good tips, and sounds easy enough.

[isco6]

The drain plug is a 16mm torx with the security hole. and the fill is a regular 16mm torx. it is behind a metal shield and when you fill it there is a plunger in the fill hole and if you push the plastic tube in too far it will get stuck. If this happens you will need to put a screw driver in the hole to un pinch the tube.
get a pump to fill the fluid.

[LJH]

Before you drain either one, make sure you can open the fill plug, nothing worse than doing it the other way around and finding out the fill is stuck for whatever reason.

X2

Ask me how I know.....

Cheers,
Jim

[JimmyBones]

I changed my MTF on my S4 when I changed my clutch and if you install a 4:1 center diff that is a great time to change the fluid since it leaks out when you pull the housing off.

I'm baffled that Audi would call it lifetime on a performance car they know gets beat on regularly. For a more ho-hum A4 with an auto trans, it can probably go a long-ass time before needing a change.

The sad part is there is a interval for changing certain fluids with the basic A4s. The CVT Fronttrak transmissions get a change at 35K or 40k miles depending on the year and those transmissions still failed regularly. The DSG transmissions also need a fluid and filter change for the A3s, TTs, and B8 S models.

[JimmyBones]

The drain plug is a 16mm torx with the security hole. and the fill is a regular 16mm torx. it is behind a metal shield and when you fill it there is a plunger in the fill hole and if you push the plastic tube in too far it will get stuck. If this happens you will need to put a screw driver in the hole to un pinch the tube.
get a pump to fill the fluid.

My MTF drain and fill plugs were 10 mm Allen holes along with every other B6/7 S4 I have seen.

[jlink38]

I'm using Fuchs 75w-80 in my trans and Castrol GL-5 75w-90 in the rear diff. The Fuchs I have been running since my transmission was rebuilt but I feel like the Redline MT-90 I was running before the trans rebuild gave me more fluid shifts. I might switch back in another 30k miles or so and see the difference.

[dparm]

Why are you running 75w80? The car is spec'd for 75w90. You're sacrificing high-temperature protection and accelerating wear.

[jlink38]

Why are you running 75w80? The car is spec'd for 75w90. You're sacrificing high-temperature protection and accelerating wear.

Fuchs titan 75w-80 is 75w-90. Scotty from Advanced called Fuchs and verified. No idea why they label it an 80 and I don't really think they know either. Weird stuff.

[vdubjetta02]

gear 300 = $20 per liter?

[madkimchi]

I'm using Fuchs 75w-80 in my trans and Castrol GL-5 75w-90 in the rear diff. The Fuchs I have been running since my transmission was rebuilt but I feel like the Redline MT-90 I was running before the trans rebuild gave me more fluid shifts. I might switch back in another 30k miles or so and see the difference.

i have Redline MT-90 also in my tranny and i freaking hate it. it's less than probably 10k miles old and when oil is cold it's worst than oem fluid. i will be switching out this on my next oil change. yea it is smooth when it gets warm but which oil doesn't shift smooth when it's warm? specially when the oil is fairly new.

[dparm]

gear 300 = $20 per liter?

You can get it cheaper if you shop around, and even cheaper still if you order it by the case (which is enough for two full MTF and rear diff changes).

OEM fluid costs more than $20/L, by the way.

[wws]

What is a good fluid pump to buy? I have to change my MT and Diff fluid as well.