I should note up front what is probably a major reason there is not much info out there on the subject. According to BMW/MINI, the manual transmission fluid is a “lifetime” fluid and does not need to be changed. If you have ever been under a MINI, you’ve probably seen the big yellow sticker on the bottom of the transmission indicating this.
I’ll also note that I relied on a couple forum threads on the Internet to help me. The first was at minitorque where another 2nd gen owner was doing his. That included a link to a thread at the Lone Star Mini Club web site describing an R53 fluid change, which is pretty much the same process (as it turns out).
Now, on to the DIY stuff. First up is getting together the tools and some fluid. Since there is not much info out there, I’m not real sure what all the options one may have. I ended getting some Red Line MT-85 75W85 oil based on some reviews I found on-line. I did note that according to the Red Line web site, their “recommended” oil is actually the MTL 70W80 oil. Royal Purple makes some stuff called Synchromax that may be an option (I use RP motor oil, but found too many poor reviews of the MT fluid to feel comfortable with it). Amsoil has some options as well. Of course, I’m sure one could probably order some MINI OEM fluid as well. I gather that one thing you need to be sure of is that whatever you select meets the GL-4 specification. On a side note, instead of ordering direct from Red Line, I got mine through bimmerworld only because the shipping was a tad cheaper (and even though I only paid for regular ground shipping, since it was just coming from Virginia, it arrived next day).
Only a couple specific tools are needed. The first is a 8mm hex head socket to go on your ratchet. These will be used to loosen and tighten the plugs. I couldn’t find these at auto parts stores, but our local Home Depot had a metric set of hex heads. The other item is a funnel with a tube. I ended up making my own out of a funnel I got from Advance Auto and some 3/8 x 1/2 clear vinyl tubing I got from Home Depot. The 1/2 inch tubing ended up fitting in the fill plug perfectly. I would strongly recommend clear vinyl. To really do things properly, you should have a torque wrench. You’ll need a container to catch the old oil that comes out. I’d recommend a good, thick, large piece of cardboard to help catch spills. So our list is:
- 8mm hex head
- Breaker bar/ratchet
- Torque wrench
- Funnel with tube (1/2” diameter)
- Oil catch pan