[jwzimm]

Hey all,

I am getting fairly confused here. I am looking to change the fluid in my tranny and I am trying to figure out what the OEM fluid is. Thanks to BMW's "lifetime" crap they don't list it in the manual.

I have contacted Jason at Tischer and he says it takes MTF-LT-3 fluid and they have a 5 liter bottle for sale (I only need 2 for crying out loud). I also called my dealer and they said I need MTF-LT-2 and they have .5 liter bottles available for sale. I have also seem much discussion on here saying you are supposed to use ATF in these trannys.

My question is, which is it?!?! Any thoughts?

[nate5ks]

I'd like to know also, I plan to do this soon.

[kaede]

Depends on the pricing, 5 litres isnt that bad if its a good deal (that is because i change my tranmission fluid once every 2 years). I believe for the 335i we use the LT-3. I change mine with royal purple synchromax and it shifts a bit smoother and better than the oem stuff. It's also cheaper! Good Luck!

[gtaccord]

The 6mt in the 335 uses atf. You can do a cross reference on the redline oil, royal purple or many of the other oil websites.

I personally just changed mine to Redline D4ATF. I didn't notice a huge difference over the 68k mile old factory fill but there was a difference.

[jwzimm]

^^ I saw this at the Redline website too. I am not 100% sure though. I have two independent dealers telling me you are supposed to use MTF and not ATF. I am more inclined to believe them over the aftermarket. I think I will go with the LT-3 stuff.

[Surly73]

My 2007 E90 328i came from the factory with MTF-LT-3. The dealer recently did some third party warranty work and that's what they refilled or topped it up with.\

LT-3 is thinner than LT-2 if memory serves correctly. Generally the "other" companies like Redline spec ATF so that shifting is super-easy and no one in cold temps complains about their fluid. In reality, ATF is usually a little on the thin side compared to what is most beneficial for wear protection for gears and bearings.

I drive bimmers through Canadian winters and I've always used a somewhat thicker than ATF fluid designed specifically for synchromesh manual transmissions. My favourites are Redline MTL and Amsoil MTF.

I had Amsoil MTF in the gearbox when the dealer but LT3 in.

[jwzimm]

Well I just went to the dealer and it turns out my car needs MTF-LT-5 fluid. I have the printout they used. It says:

"All vehicles equipped with a manual transmission (GS6-45BZ) and the N55 engine require MTF-LT-5 long-term fluid."

The part number on the bottle is 83 22 2 239 654. It's says it is SAE 75W80 oil.

I'm going to confirm the transmission. Part number before I change it but this looks like the stuff.

[Crusader]

I'd go with Redline MTL. A bit more viscosity, but more protection at the expense of the requirement for a bit slower shifting in the cold. Check out Mike Miller's old school maintenance recommendations.

[jwzimm]

Just changed it today. I used the BMW fluid as I didn't want to risk and potential impact to warranty. The shifts are not super different but it does feel a bit smoother. The main reason I did this is I wanted to get the oil that was there for the break in out.

[Sparkee]

I used Redline D4 in mine when I changed it last fall. Redline says D6, but I read somewhere that both D4 and D6 are OK. Supposedly Redline says D6 because the shifting can get a bit notchy in really cold weather with the D4. Here in MD last winter, it behaved pretty well but did get a bit tight on 20 degree F days.

[Casca]

Originally Posted by jwzimm

Just changed it today. I used the BMW fluid as I didn't want to risk and potential impact to warranty. The shifts are not super different but it does feel a bit smoother. The main reason I did this is I wanted to get the oil that was there for the break in out.

Good choice. I am not so concerned about a slightly better shift as I am with being certain the fluid provides the...lubricity...needed to properly protect the transmission. I have read about certain aftermarket fluids destroying transmissions before....although they did make the transmission feel like it shifts better. Why would a different fluid feel like it shifts "smoother"? Maybe because it is thinner than OEM? Is it better that the fluid is so different than OEM that it changes how it feels to you? Maybe BMW went what they went with because it provides better protection. I really don't know, but I think I'd rather trust the engineering and design choices of the people at BMW than the ones at Red Line, Lucas Oil or Royal Purple that are making one fluid for all sorts of application. BMW wants to use LT-2 for this year to this year E90, but only LT-3 for another block of year and in your case LT-5. Red Line says, use ATFD4 or D6 for all BMW's...depending on your climate.

On your transmission, there should be a tag that states what fluid to use. This is not for you as it is for someone else that might be wondering what to use. Mine takes MTF-LT-3 and that is what I went with. Seems the safest thing to do is use what BMW approves and tested for the transmission they designed. Maybe I do too many arm curls, but it seems to shift easily for me with the OEM fluids and I'd just be splitting hairs to notice if it shifts better with something else. My car is not a race car and I have no wish to increase my chances of a transmission change in order to have better shifts.

[jwzimm]

Originally Posted by Casca

Good choice. I am not so concerned about a slightly better shift as I am with being certain the fluid provides the...lubricity...needed to properly protect the transmission. I have read about certain aftermarket fluids destroying transmissions before....although they did make the transmission feel like it shifts better. Why would a different fluid feel like it shifts "smoother"? Maybe because it is thinner than OEM? Is it better that the fluid is so different than OEM that it changes how it feels to you? Maybe BMW went what they went with because it provides better protection. I really don't know, but I think I'd rather trust the engineering and design choices of the people at BMW than the ones at Red Line, Lucas Oil or Royal Purple that are making one fluid for all sorts of application. BMW wants to use LT-2 for this year to this year E90, but only LT-3 for another block of year and in your case LT-5. Red Line says, use ATFD4 or D6 for all BMW's...depending on your climate.

On your transmission, there should be a tag that states what fluid to use. This is not for you as it is for someone else that might be wondering what to use. Mine takes MTF-LT-3 and that is what I went with. Seems the safest thing to do is use what BMW approves and tested for the transmission they designed. Maybe I do too many arm curls, but it seems to shift easily for me with the OEM fluids and I'd just be splitting hairs to notice if it shifts better with something else. My car is not a race car and I have no wish to increase my chances of a transmission change in order to have better shifts.

Thanks. Just to note, my transmission did not have any stickers telling me what to use. I think they stopped putting those on at some point.

As an engineer I agree with what you say. The transmission was designed by ZF and a considerable amount of research and development went in to the selection of a fluid for the unit. The exact specifications of the fluid were used to analyze the performance of the transmission. That is why I wanted to use the exact fluid that was to be in it.

[Surly73]

Originally Posted by jwzimm

Well I just went to the dealer and it turns out my car needs MTF-LT-5 fluid. I have the printout they used. It says:

"All vehicles equipped with a manual transmission (GS6-45BZ) and the N55 engine require MTF-LT-5 long-term fluid."

The part number on the bottle is 83 22 2 239 654. It's says it is SAE 75W80 oil.

I'm going to confirm the transmission. Part number before I change it but this looks like the stuff.

A 75W80 rating on the gear oil chart is equivalent to Redline MTL and Amsoil MTF, for those who may be interested. That's thicker than ATF (especially D6/Dexron 6 compatible fluids).

[Surly73]

Originally Posted by jwzimm

Thanks. Just to note, my transmission did not have any stickers telling me what to use. I think they stopped putting those on at some point.

As an engineer I agree with what you say. The transmission was designed by ZF and a considerable amount of research and development went in to the selection of a fluid for the unit. The exact specifications of the fluid were used to analyze the performance of the transmission. That is why I wanted to use the exact fluid that was to be in it.

Well, the catch is that this "OEM fluid" business seems to be quite a racket. For instance the "LT71141" fluids used by many ZF automatics... Genuine Esso LT71141 is an unremarkable SEMI-synthetic fluid that sells for something like $20/L. The only thing important about LT71141 is the friction modifier package specifications so that the AT behaves (and wears) as ZF designed.

Valvoline Maxlife ATF is a VERY inexpensive ATF which carries LT71141 compatibility and provides a very affordable price point for those who change fluid often. It's less than $15/gallon I think. On the other end of the spectrum, Amsoil ATF also lists LT71141, is fully synthetic, and is some of the best ATF on the market today (and still costs less than genuine LT71141).

I DIYed a pan drop, filter change, fluid flush to Amsoil ATF on an E39 540i which had pan drop, filter change, drain/refill every 30k miles all it's life with genuine LT71141 at a dealer. The car had around 200k km on it when the Amsoil went in and immediately on the test drive it shifted better than it ever did on genuine fluid and resolved some weird problems that were popping up.

When choosing a fluid you have to be careful when you're servicing a "precision machine" which has a greater-than-average level of complexity or refinement. On the other hand, you can often distill down to a small number of key requirements which can then be used to narrow choices down to your shortlist.

[jwzimm]

Originally Posted by Surly73

Well, the catch is that this "OEM fluid" business seems to be quite a racket. For instance the "LT71141" fluids used by many ZF automatics... Genuine Esso LT71141 is an unremarkable SEMI-synthetic fluid that sells for something like $20/L. The only thing important about LT71141 is the friction modifier package specifications so that the AT behaves (and wears) as ZF designed.

Valvoline Maxlife ATF is a VERY inexpensive ATF which carries LT71141 compatibility and provides a very affordable price point for those who change fluid often. It's less than $15/gallon I think. On the other end of the spectrum, Amsoil ATF also lists LT71141, is fully synthetic, and is some of the best ATF on the market today (and still costs less than genuine LT71141).

I DIYed a pan drop, filter change, fluid flush to Amsoil ATF on an E39 540i which had pan drop, filter change, drain/refill every 30k miles all it's life with genuine LT71141 at a dealer. The car had around 200k km on it when the Amsoil went in and immediately on the test drive it shifted better than it ever did on genuine fluid and resolved some weird problems that were popping up.

When choosing a fluid you have to be careful when you're servicing a "precision machine" which has a greater-than-average level of complexity or refinement. On the other hand, you can often distill down to a small number of key requirements which can then be used to narrow choices down to your shortlist.

While you make a good point my point still stands; I was not involved in the detailed design decisions and therefore am not equipped to second guess the choices the manufacturer made. Throw in the risks to voiding your warranty and I would prefer to pay the extra cash to put in what the experts decided on rather than risk having the transmission fail. Even if it was not due to the use of a non-OEM fluid, the simple fact that you used it will cause BMW to tell you to pound sand.