One problem related to gasoline engine has been reported for the 2006 Infiniti G35. The most recently reported issues are listed below.
2006 Infiniti G35 coupe 6-speed manual transmission 1- noticed the oil levels were too low before 3000mile. 2- engine's low oil levels would cause a noise in the engine and performance decreases, until additional oil was added. 3- I had to take the car into the dealer every 1000miles to monitor the loss of oil. (which was 1. 5 to 2. 5 quarts every 1000miles. ) after 5 such check ups, Infiniti approved replacing my engine. Engine was replaced this week. (10-18-07).