The vehicle consistently exhibits a shudder (vibration, tremor) when (1) the vehicle is warmed (driven at least 10 miles from cold start), (2) moving at a speed above approximately 30 mph, and (3) the throttle pedal is depressed. usually, but not consistently, the shudder immediately dissipates when pressure to the throttle pedal is released or when the transmission is put into neutral while the vehicle is moving. additionally, when the vehicle is driven into and in a right hand curve, the shudder is not present regardless of any or no pressure on the throttle pedal. in a left hand curve, however, the shudder is present often without any throttle pressure. when coasting on a straightaway the vehicle typically, but not consistently, exhibits no vibration. infiniti has found this defect in other q70s since my reporting of the problem on 20 may 2015. cause/source of problem has not yet been identified to my knowledge. implication of problem on vehicle safety, if any, has yet to be determined.