Get a Toyota Highlander next time 
My first car out of college was a Nissan Sentra 2006. It made a "chirp"/squeal noise while changing gears from 2nd to 3rd on the highway. similar to what you are talking about. Took it to the dealer several times since there was a TSB on it. Transmission failed at 33K ....thankfully, warranty covered it.
My new car is the 2009 Toyota Camry SE. Gladly passed up on the Altima and paid the extra money to get this car. Sorry, I am not talking from prejudice but from experience.
You should have looked at the Highlander
My first car out of college was a Nissan Sentra 2006. It made a "chirp"/squeal noise while changing gears from 2nd to 3rd on the highway. similar to what you are talking about. Took it to the dealer several times since there was a TSB on it. Transmission failed at 33K ....thankfully, warranty covered it.
My new car is the 2009 Toyota Camry SE. Gladly passed up on the Altima and paid the extra money to get this car.
Sorry, I am not talking from prejudice but from experience. You should have looked at the Highlander
