What fluid for green tag g260 that I can get locally?

[16vCorey]

I know the topic has been beaten to death, but with search after search I cannot find a definitive answer. I'm finishing up a 5 speed swap, and the trans has the green "special oil" sticker. It seems that everyone agrees that Redline MT-90 is best, but no one in town (that I know of) carries Redline. I've also read some people say to use synchromesh, and I've also read that the green tag transmissions take synthetic, but they didn't say what weight or type.

So someone please help me out. What's the best oil for a g260 with a green tag that I can get TODAY?

[jlevie]

As best I can tell, almost all of the internals of E30 manual transmission are the same. And the few differences don't correspond nicely with the various tag changes. My theory is that BMW changed (for whatever reason) the fluid used and the tag was to tell a tech what to use if the transmission needed to be topped up. If you are draining the fluid you can refill with any of the fluid types. MTL is good as is ATF.

[Saeulf]

I am in the search for a replacement fuild and I also have the green tag. I think I might just go with what Red Line recommends (MTL 70W80), but I think you should be good with any synthetic GL-4 70W80 gear oil or thereabouts.

I have heard that ATF is NOT ok for use in the green labeled transmissions.

[jlevie]

Well the internal parts of the green tag and other transmissions are the same...

[Saeulf]

So, if the internals are unchanged and the lubricant doesn't need to be changed, then why go through the trouble of putting a tag on the tranny that says "Special Oil"?

[16vCorey]

I was told that the green tag transmissions have different synchros, but I have no proof of that.

[jlevie]

So, if the internals are unchanged and the lubricant doesn't need to be changed, then why go through the trouble of putting a tag on the tranny that says "Special Oil"?

My theory is that BMW changed the fluid used during the production life of the cars reasons known only to them. The tag was there to tell a tech what fluid to use if the transmission needed to be topped up.

[Saeulf]

I was told that the green tag transmissions have different synchros, but I have no proof of that.

I think they are made of brass and the special fluid is required to prevent corrosion... but I also have no proof and am only going off what I have read on other forums.

My theory is that BMW changed the fluid used during the production life of the cars reasons known only to them. The tag was there to tell a tech what fluid to use if the transmission needed to be topped up.

The fact remains that there IS a reason and we can't just throw any fluid into our tranmissions (well, we could, but it would be wise to make educated decisions).

[Saeulf]

My theory is that BMW changed the fluid used during the production life of the cars reasons known only to them. The tag was there to tell a tech what fluid to use if the transmission needed to be topped up.

Aw, I just realized what you mean. You are referring to the mixing of fluids that might not play nice together! Sorry about the miscommunication. That makes sense, although, I still think that there might be physical differences between the transmissions that warrant different fluid use.

[jlevie]

Aw, I just realized what you mean. You are referring to the mixing of fluids that might not play nice together! Sorry about the miscommunication. That makes sense, although, I still think that there might be physical differences between the transmissions that warrant different fluid use.

Go spend some time with the IPB and try to correlate what little differences there are with transmission internal part changes and with the different stickers. I can't find a correlation. But maybe I missed it.

[ROLLingKING]

75w90 royal purp