[Mcdubh]

Hi,
Any one yet put some synthetic transmission oil in the gear box?
I did that on my BMW motorcycle, Man what a difference in chifting.

[fredtoo]

There is a huge sticker on the tranny that states it has a lifetime fill.

[AZMike]

BMW used to use MTF-LT-1, which was essentially a 7.5cst (DexIII viscosity) oil, which was later replaced by MTF-LT-2 (which was thicker), but claimed backwards compatiblity to MTF-LT-1 apps. There was recently a post on this site by someone who suggested that MTF-LT-3 is now the factory fill for the E90 manual transmission, and I have no clue if that fluid is similar to the MTF-LT-2 or MTF-LT-1 fluids at all. I'll be checking with the tech depts at Redline and Royal Purple to see if it is similar to the MTF-LT-1.

People on the M5boards have used Royal Purple Synchromax in place of the MTF-LT-01, and others have used Redline D4 ATF in place of it. D4 ATF works well but appears to require replacement every 15K or so to maintain good shift quality. Then again, I'm not sure if a MTF-LT-1 "like" MTF can be used safely in the E90 transmissions because it now uses MTF-LT-3 supposedly, so I'll be checking with the people at Redline and Royal Purple.

For fun, I decided to make a comparison of the fluids (OE MTF, RP Synchromax, MTFGlide, and D4 ATF). Note, that this is probably not the best way of comparing the fluids, but its worth looking at:

[Mcdubh]

Thank you Mike for checking all that...

[AZMike]

Here are my responses from Royal Purple and Redline:

1)
Michael,
I am unfamiliar with MTF-LT-3, they recently switched to the MTF-LT-2
in '05 models. We won't have our 2006 lubrication guides until about
April. If you have a sample of the LT-3 fluid I can have the chemist
check the viscosity. At this point I would expect the D4ATF would
still be a suitable replacement for the LT-3 fluid.

Regards, Dave
Red Line Oil

2)
That is actually a question better answered by someone at BMW.

As for using Synchromax in a new BMW 6 speed transmission. If it were mine I
would change it the day I brought it home.


Patrick Burris
Motorsports Marketing Coordinator
Royal Purple
One Royal Purple LN.
Porter TX. 77365
281-354-8600 ext. 241
713-705-9201 cell

[topracer]

I want to know if the Redline D4 ATF fluid is going to fix the gear clash problem on a 6 spd manual?

[montreal_bimmer]

i changed the fluid in my E46 to the Redline, and WHAT a difference....

i wonder if it has the same effect on a step transmission???