Did mine today, 93k miles. 2000 323i. I have the GM 360R transmission.
Used Fuchs Titan 4000 ATF, $ 9/liter - 7 liters + the new filter kit was $93 delivered from KO performance. By the way, on the Fuchs ATF bottle it says Dextron III g.
Got to say thanks for the awesome DIY, would never have tried this myself.
For me the worst part was getting the car jacked up high enough. Tried to lift the front from the center jack point but ended up doing one side at a time, I could get a higher setting on the jack stands that way. Rear end was a relative breeze, used the U-brace in front of the differentialand lifted both sides at once.
2nd worse part was the refill, just really messy (I'm a klutz, and didn't have help).
Finally, getting that damn fill plug out and then in sucked. I didn't have the L-shaped t45 torx wrench, used a 5/16 box wrench over a 3/8"drive torx socket bit (this was demonstrated on the diy on the wiki). Pulling on it did nothing, but a couple shots on the wrench with a hammer, and it loosened up. I was shocked, my plan B was to just go to AAMCO to change the fluid/filter for me if I couldn't get the plug out. No way for me to get a beaker bar under there. My advice is to get the damn L-shaped tool.
The old atf was dark, but didn't smell burned. Got about 5.5 L out.
I decided to change mine because a couple weeks ago when it was cold (for texas-30's), I got the transmission warning, and the shifts to first and second were VERY hard. The problem cleared when it warmed up, but after researching and reading the boards, decided to change it.
Anyway, I'm really thankful for these boards, I've never done any work on my car (not even oil), so by my count the awesome Diy's and contributors have saved me about $ 700 in shop labor in less than a month (Thermostat/lower radiator hose change, Ac belt tensioner and belt, drivers side window regulator, and Atf fluid/filter change).
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