I have a 2005 545i with automatic transmission and 81,000 miles. I have owned the car since new and kept it strictly dealer serviced. Recently the transmission has started going into "safe" mode, meaning it selects 3rd gear and stays there. Shutting off and recranking the car will clear the fault and it operates normally, for a few weeks, when without warning it will again enter "safe" mode. I took the car to the dealer for diagnosis and repair and was told--the transmission is detecting slippage (none apparent to the driver by the way) and then dropping into "safe" mode. Further I am told, BMW sells no individual parts to the transmission so the repair will.....require a new transmission, at $6000 plus labor to replace. YIKES!! Is there another solution or remedy? I have located "rebuilt transmissions, new OEM" on the web but know nothing about their reliability or service expectations. Any help appreciated, thanks.