Thanks for the input. I'm going to play a little bit of devils advocate and offer some food for thought. I'm not discounting your opinion, but I'm a firm believer in changing your fluids, nothing lasts forever.

Yes, the ESSO LT71141 fluid is superior to regular mercon/dexron III but the most notable difference on the specs sheets are the LongLife or LifeTime additives packages that are added to the fluid more so than the sheer properties etc. Esso also says that this specific fluid only has a 3 year shelf life. Three years? How is it supposed to last a life time in an environment that is much harsher than that of a bottle. I have the spec sheets somewhere but I'll save that for another time, to save me going on a rant.

Not to mention I have a land rover with the 4HP24 (basically the same transmission with an extra gear) and it uses mercon/dexron III, and it's kind of funny to see every big car manufacturer (AUDI, BMW, JAGUAR, RANGE ROVER) with the exact same transmission 5HP24 , all use their own "SPECIAL FLUID"... Sounds more like a clever Marketing ploy than science to me. (Especially at $30/liter)

I must say that I am typically pretty abusive to my car, continually redlining my poor baby to say the least, and I am surprised how I have not noted any wear (metal or clutch) in the pan of my transmission since changing the fluid. The old fluid had quite a notable amount of soot and metal, and I particularly point my finger at fluid breakdown. If on the other hand my friction material and clutches burned out or grenaded, yes, at that point I would think using this fluid was definitely a bad idea, but that is not the scenario.

The main reason however, is the fact that we all know that the No Reverse on these transmissions, (X5, 7 SERIES, 5 SERIES and even similar on the 3 SERIES) have been occurring quite prominently, there are even many, many site dedicated to these very symptoms.

http://www.noreverse.org/

Most people have been unlucky and haven't even made it to 170,000km as I have, and lots have considerably lower millage. At the end of the day my point is, this also happens to people that do exactly as BMW says, and leave the transmission fluid intact or replace with the 71141. It may even seem that it actually happens more, but I think this is more due to an internal design flaw. As BMW made recall to the 7 series http://forums.audiworld.com/a8/msgs/150731.phtml

Something else to note is how BMW changed their service schedules a few years ago from the regular changing of all fluids at some point in time to the LifeTime everything after they started including service with purchases of new vehicles...

I have a feeling I may in fact have hit a tender subject, but I welcome the discussion. However I do not endorse the use of non recommended fluids, I just don't feel that paying $30/liter is justified and wanted to prove to myself there were alternatives.

I am trying to get my friend to fix my transmission for a couple cases of beer, I just have to get it out of the x5, and being under the car yesterday it looks as if it is going to be one PITA, anyone have any suggestions?

Regards,
Frank