AFTER MULTIPLE ATTEMPTS TO REMEDY THE SITUATION, BMW HAS BEEN UNABLE TO RESOLVE THE TRANSMISSION AND THE INTERMITTENT LOSS OF POWER AND MOST RECENTLY "LIMP-HOME" MODE OCCURRENCE ASSOCIATED WITH THE DRIVETRAIN ON THE 2007 BMW X3. THE SYMPTOMS 1ST PRESENTED ITSELF AS A LOSS OF POWER FROM A START. UPON PRESSING THE ACCELERATOR, THE VEHICLE DID NOT RESPOND AND THEN RESPONDED WITH A SURGE OR LURCHING FORWARD. THIS MAKES FOR UNPREDICTABLE AND DANGEROUSLY ERRATIC VEHICLE PERFORMANCE. AFTER MULTIPLE VISITS (+4) AND MULTIPLE COMPLAINTS ALONG WITH THE SOUND OF GEAR OR DIFFERENTIAL NOISE, THE DEALERSHIP FINALLY DID SOME TYPE OF ECU UPDATE THAT APPEARED TO RESOLVE THE PROBLEM. THE NOISE NEVER SUBSIDED AND RECENTLY THE CAR WAS INOPERABLE FORCING A TOW AFTER UPON PRESSING THE ACCELERATOR THE VEHICLE WENT INTO TRANSMISSION LIMP-MODE. AS USUAL, THE SYMPTOMS "CAN'T BE DUPLICATED" ONCE CODES ARE CLEARED YET THE ECU IS THROWING MULTIPLE CODES FOR TRANSMISSION LIMP-MODE AND CODE 56BE FOR CLUTCH GEARS 2 AND 6. I BELIEVE THAT THIS IS A VERY DANGEROUS SITUATION TO EITHER PRESS THE ACCELERATOR AND FOR IT TO BE NON-RESPONSIVE THEN HAVE A DELAYED VEHICLE SURGE NOT PROPORTIONAL TO THE INPUT AND TIMING OF THE ACCELERATOR DEPRESSION AND/OR PRESS THE ACCELERATOR AND EXPERIENCE SIGNIFICANTLY CURTAILED VEHICLE POWER DUE TO THE "LIMP-HOME" CONDITION. THIS HAS BEEN A RECURRING ISSUE SINCE THE PURCHASE OF THE VEHICLE ON 5/31/2009.