One problem related to transmission noise has been reported for the 2004 Mini Cooper. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 Mini Cooper based on all problems reported for the 2004 Cooper.
2004 Mini Cooper with 60k miles. Transmission failed and was advised by Mini Cooper dealer needs replacement, makes whining noise at higher speeds. Have not driven car since April 2011. Can not afford $5k replacement cost.