Too many variables.. pengsan..
1. By default, BMWs gearbox is design to last 160k km as a rule of thumb, assuming not ATF change since day 1.
2. Average KL/Selangor car usage is about 30k per year, average yourself using existing odo reading over car age, while the Japanese recond is about 5k km per year.
3. If overhaul was done on both gearbox and engine, then you might reset the "mileage" for these 2 items.
Look for other clues which gives a good indication on the mileage clocked for the car because mileage can be tempered,
~ is the spare tyre still original/new Conti?
~ How worn is the brake pedal rubber cover?
~ How worn is the front/rear brake rotor?
~ Sludge sign under the engine oil cap?
2004 car should clocked 150k km if the 30k km/year formula is used. If below 120k km then is consider low mileage lor. If 150k km then, its its fair usage lor... but gearbox gonna kong anytime if ATF not change.. they sure tell u they change..
So good luck!