One problem related to transmission shudder has been reported for the 2008 Nissan Altima. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2008 Nissan Altima based on all problems reported for the 2008 Altima.
Purchased a 2008 Nissan Altima, drove the car for 3,000 miles. Cvt transmission started making strange noises. Turned out to be defective. They replaced it, but did not put it back together properly. Been having problems with it ever since. Nov 30, 2009 took vehicle in for scheduled maintenance, had them examine transmission again for a grinding noise. They did not "see" anything wrong with it but acknowledged transmission could be defective. Car is going in for more "tests". Nissan extended the warranty to 10 years 120,000 miles for cvt's, however I don't feel safe driving the vehicle.