Manual Transmission Fluid?

[LNLYCRPR]

So I'm going to do a fluid change on the Transfer Case, Differentials and Transmission.

I already went to the dealer to buy the specialized Transfer Case fluid. Much research has shown the type of gear oil needed for the differentials, I am however, at a loss for what the transmission truly takes...

According to several websites; BMW Tranny Fluid or an MTF-LT-3 equivalent is what's supposed to be used for fluid. I have also read that Redline MTL (75w80) has been used with pretty good results as well.

Problem I'm running into is this; when I search MTF-LT-3 equivalent, a Dexron VI ATF, or Valvoline Synchromesh comes up as the answer.

Which one should be used exactly?

Something in my gut tells me not to use ATF in a manual transmission. When I cross reference Transmission fluid (MTF-LT-3) through Pelicanparts.com or ECStuning, it shows a synthetic 75w80 gear oil. It also references Red Line MTL which is really a 75w90 synthetic gear oil.

So has anyone here changed their own manual transmission fluid? What did you use and what were your experiences/results?

I'm curious because I'm going to do the fluid swap this weekend. If I can't get an answer, I'm either going to hold off or just go for a 75W90 full synthetic... thoughts?

'09 X3 Manual Transmission

[E38flagship]

I had this issue but not with an e83 with my e32 I purchased redline 75/90 to run in my manual trans. Upon installation I see a sticker indicating to run ATF only, I ran redline syn auto trans fluid. It’s been over 40k no issues no noise, I’d stick with what ever they recommend. They may not use gear lube anymore as when it’s very cold it becomes extremely viscous, if you own or have ever owned an older bmw you will know in winter time you have to wait for the trans to “warm up” because the shifting force required may be higher

[motordavid]

Fwiw, I had my Indie R&R the manual trans fluid at ~60k+ miles and again this past summer at ~115k miles, using Redline MTL 75-90W, per his recommendation.

He also had MT 90W, but he said he only uses that in the P Cars he works on that get tracked regularly.

Our '01 E53 5 Spd has shifted flawlessly over its 16 year life...I thought of a DIY, but too old to be crawling around under cars on the cold garage floor.

GL, mD

[LNLYCRPR]

After reading a bunch on other forums and taking input from a bunch of different people, I went ahead and pulled the trigger on Red Line 75w90 for the tranny.

Something still doesn't sit right with me about ATF in the tranny. If the Red Line doesn't work well, maybe I'll try it. For now, I'll see how it works.

I appreciate the input guys.

[jeepo23]

If you dont want to buy BMW OEM fluid, you can use Redline D6.

It meets the BMW MTF-LT-3. I put it in a year ago in my 6speed and works flawlessly. Shifting butter smooth even in cold Canadian climate.

[peete]

I put Redline MTL in all my manual transmissions. It smooths out cold shifting.