Never seen the "T" designation on an X3 before, but the N52T is a 3.0L engine that is cut down to 2.5L displacement, much like the N52 2.8L. N52T is rated at 201hp while the 2.8L is rated at 240hp.
The "T" designation is probably just a mistake as it doesn't appear to have ever been used in an X3.
