I have a 2000 pontiac montana. i never had a tranmission problem with it but just the other day i was at a traffic light and the car just stopped moving. it went into the gears no problem but it wouldn't move regardless of what gear it was in. i dout its the transmission becuz in my experience the car usually starts giving u signs that the transmission is going it doesn't just stop working out of the blue. so what do u think it could be. one guy told me it might be the sending unit on the transmission. so u think u can point me i the right direction???