I have a nissan 300zx 2+2 none turbo and the problem i have is the transmission making a grinding sound in all gears except in neutral and reverse. it only grinds when i give it more gas but the sound goes away around at 2000rpm. I've checked the gear oil in the tranny and its like new and the same for the drive shaft. could it be the clutch, flywheel, or the transmission it self. what do you guys think it is

 

here is the video that explains about the sound that my car makes

http://www.youtube.com/watch?v=F_OjG7VC35k

 

Just went to Vildini motorsports today which specializes in z cars and found the problem.

Its the transmission itself that is making that sound so tomorrow I'm gonna get the tranny

switched with a rebuilt one.