Hi Scotty, I have a 2015 BMW F32 4.28i with the ZFHP 8 speed auto transmission. It has 50,000 miles on it and I asked my independent BMW specialist to change the transmission fluid. He said he would not change the fluid unless I take on the risk of it ruining the transmission. I have heard of this happening in e46 auto transmission on the odd occasion. Is this something I should really worry about with a ZFHP? I really think I should change the transmission fluid every 40-50 thousand miles? What do you think? Should I not do it, take it to another mechanic, or just have the guy I trust do it?
I have a ZF transmission in my car and never heard of an oil change ruining such transmissions.
The only situation I heard of where an oil change can ruin a transmission is if you never changed your oil for 120+ thousand miles - then a "sudden" oil change can make hidden problems vivid.
Your 50 000 miles are just about double the mileage I am doing my regular oil changes at, so if I were you I would not be worried about that (yet).
I would just change the oil, then (bearing in mind that you sort of skipped one oil change, and that the transmission would never let you drain old oil completely) drive a couple of miles and change it again - this time taking the transmission oil pan off and replacing the pan gasket and the atf filter as well. It is not difficult - I have done it myself multiple times. That would be it. And upon that, I would switch to changing the atf fluid at regular intervals - that without dropping the pan and replacing the filter.
What does the owner's manual say? If it's time for a fluid and filter change per the manufacturer, find a mechanic who will work with you, not against you.
I've never owned a BMW, but fluid is fluid. It breaks down - and if you plan on keeping the car until it dies or is on its last leg - yes I would also be draining & refilling the fluid. I would NOT flush the system though, just a straight drain/refill.
Hopefully Scotty or a Euro car specialist can advise further. But things like this are what started me doing most of my own car work... I had a shop basically tell me I was stupid that I wanted to change the trans fluid in my 2011 GT when it hit 65k miles. So, I went and found a mechanic that actually listened to me.
But you can definitely do the drain/refill yourself. YOU CAN DO IT!!
