Just wanted to share my experiences with BMW auto transmission.

My last car 2000 E46 328ci (purchased at 29,000 miles) lost reverse at 165,000 miles, original fluid. I paid $1400 to have it repaired at an independent shop. Sold the car at 185,000 miles.

My brother's 2000 E46 323ci currently have 185,000 miles on the original fluid. No problems so far.

Another brother's 2002 E46 330ci, 132,000 miles on the original fluid. No problems so far.

My current BMW E70 4.8i have 68,000 miles. I'm not planning to do any transmission fluid service on it.