Lexus Repair: RX300, dependable car, college car

Question
have 2000 RX 300 model - daughter driving home from school hears a whurring sound and the a loud sound of some kind and it disengages from accerlation - motor runs fine and everything else seems okay - took to mechanic in rural  town  says needs new transmission - he got it to drive but says it still has a noise - he recommmended not driving it far.  Talk to dealer and they say hardly ever would it need new transmission at those miles -  My problem - it has 74K miles - there is no Lexuse dealer close - who do I trust to fix this - I need to keep this car for her a college car - and it will be on the road a lot - bought it used and also bought what I thought was a dependable car in a Lexus - any suggestions -  

Answer
Hello Lisa, Dependability is only going to be as good as the person who is servicing your vehicle. If the vehicle is not taken care of properly either by not following the service recommendations set by Lexus or that the person working on it is not experienced with Lexus thus not performing maintenance when needed or installing the improper fluid in the trans, the life of the trans will be a short one. I would bring it to Lexus for the repairs so that you will not have anymore let downs.