One problem related to transmission not engage has been reported for the 2008 Nissan 350Z. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2008 Nissan 350Z based on all problems reported for the 2008 350Z.
When rpms are high in first gear, the clutch disengages to the halfway point and you lose all power to the wheels. This is usually followed by a burning clutch smell. It is my understanding that Nissan recalled the 2007 350z for the same issue (clutch slave cylinder), but it's apparent that the problem continues with the 2008 model and I'm asking that the NHTSA instruct Nissan to extend the fix to 2008 models.