Had the car a year now, and its now got 34000 miles on it. reg nov 2001
the CVT was always a bit revvy (more so than I thought it should be) I bought 5 litres of LIQUI MOLY top tec 1400 on Jan the 1st this year (10 months ago) and got around to the oil change yesterday
NOTE, this oil is a synthetic and made for CVT with steel belt. It says MINI on the bottle along with a bunch of other brands, it is NOT RED it is a clear colour with a slight yellowish tinge to it.
The story so far, The box had become even more revvy and erratic recently and had developed the issue of the revs actually increasing when taking foot off the accelerator. If travelling at 60 MPH it was always at 3000 plus revs, take foot off pedal at 60 mph and it would climb to 3500 revs........and start to slow the car down with unwanted extra engine braking which is very strange. 30 mph also equalled 3000 revs all the time, never dropping below this. It was also noisy and always had been, Ive never driven another so assumed this was OK.
Im sure there are thousands of accounts of oil change methods, I was only interested in where to drain and where to fill.
Up on the lift, wire brush and clean the drain plug and surrounding area, remove the drain plug, it drained out exactly 3.5 litres of cold RED ATF. I have no idea if this was the correct fluid or not, the car has full main dealer history so it could be. Is the stuff from MINI usually red? its only dye anyway. New washer, refit plug, torque to 30 foot pounds
Battery box out which was a pig as the 10 mm bolt heads have all corroded away to little round studs with no flats, it appears the battery has been venting into the box which has done this damage to the bolt heads.
Now, the refill, this is where my method will differ from others, Im of the opinion that if you take 3.5 litres of stone cold ATF out, you put 3.5 litres of stone cold ATF back in, simple as that, no ****ing about with cycling gears, checking levels, cycling again, checking again. Just add the same as you take out, nothing more nothing less. Sure this method assumes the level was correct already but if there are issues after the change then that is the time to check the level.
So, wire-brush and clean the top filler plug and area, then remove plug and add 3.5 litres in from the top, plug back in with new washer torque to 15 foot pounds, reassemble displaced components and go for a drive.
Chalk and cheese, night and day, the box is instantly and dramatically better, gone is the revvy nature, it travels at 30MPH at 1800 rpm, 60 mph at well under 3000 and the revs drop if you take the foot off the pedal now. It also engages from cold with no bump whereas before it was like someone bumped you from behind when selecting D from cold. It is also much smoother and definitely much quieter which is of course partially down to the fact it isn't now running everywhere at 3000 revs.
Summary, if you have not changed your oil and you are not happy with the gearbox drain it and fill it with new stuff. I used liqui moly toptec 1400 because thats what I could get and I am not silly enough to think for a second that MINI make any oil or that the MINI branded oil is anything special. Ive included a pic of the oil bottle, if ive broken any rules, please delete it as Im not seeking to advertise it, just show folks what I used