You may have heard of lifetime transmission fluid. But do you believe it? You shouldn’t.
ZF recommends that you change the transmission fluid at 60k miles, yet BMW continue to market their ZF automatic transmission-equipped cars as having lifetime transmission fluid. Well, ZF has had enough, and have made a presentation, which was filmed and posted by a small YouTube channel. It’s not a new video, and it’s in German, but it has subtitles and is worth watching.
The video talks about how oil goes sludgy and sticky over time due to water in the oil evaporating during heat cycles which leads to poor shifting, as well as other consequences of not changing the transmission fluid. It also shows you how to change your transmission fluid, in case you want to give it a go yourself. The video explains it better than I can, so I’ll leave it below.
Claims of lifetime transmission fluid are nothing new. BMW have been doing it since they launched the E60-generation 5 Series in 2003, and now automatic transmission failures are relatively common, not because the transmission was a bad design, but because BMW basically told customers that it didn’t need to be maintained. Of course, failures are happening outside of the warrantee period, so it doesn’t affect BMW.
So if you’re in the market for a BMW from the 2000’s, make sure the previous owner has changed the transmission fluid at the correct intervals. Better still, buy a manual. You won’t regret it. I know I didn’t.