2006 330i has a ZF 6HP 19 box (I have actual pics from under my car so trust me this is 100% accurate). See below info from wiki, not sure how accurate and if the ZF 6HP 19 is as tough as the 26. Will try and find out some more info. Google ZF 6HP 19 and there are some documents online that probably gives exact tolerances. Good luck!
The ZF 6HP26 was the first six-speed automatic transmission in a production passenger car. Released by ZF Friedrichshafen AG in 2000, it was manufactured by ZF Getriebe GmbH in Saarbrücken, Germany.
The ZF 6HP26 uses a Lepelletier epicyclic/planetary gearset, which can provide more gear ratios with significantly fewer components. This means the ZF 6HP26 is actually lighter than its 5-speed predecessors. It also has the capability to achieve torque converter lock-up on all six forward gears, and disengage it completely when at a standstill, dramatically closing the fuel efficiency gap between automatic and manual transmissions.
The ZF 6HP26 was first used by BMW on the 2001 E65 7 Series.
Normally reserved for high end luxury and sports cars, ZF has made the 6HP26 available to Hyundai for use on its 2009 V8 Hyundai Genesis.
While the ZF 6HP26 itself is rated for a maximum input torque of 600 newton metres (443 ft·lbf), sister products with different ratings exist in the form of the ZF 6HP19 ( for use on the 2010 3.8L V6 Hyundai Exodus Coupe) and ZF 6HP32. In addition to this, several versions of the ZF 6HP26 are available depending on application and brand: ZF 6HP26, ZF 6HP26A and ZF 6HP26X.