The 6-speed manual transmission in the 2003-2006 Nissan 350Z and 2003-2007 Infiniti G35 is a popular gearbox among enthusiasts. Here are some key features and specifications:

· 6-speed manual transmission (CD009 or V6 manual transmission)

· Rear-wheel drive (RWD) layout

· Synchromesh gears with helical-cut teeth for smooth shifting

· 1st gear: 3.794

· 2nd gear: 2.324

· 3rd gear: 1.628

· 4th gear: 1.250

· 5th gear: 1.000

· 6th gear: 0.794

· Reverse gear: 3.483

· Final drive ratio: 3.692 (350Z), 3.357 (G35)

· 240mm or 250mm clutch diameter (depending on the model year and trim)

· Hydraulic or cable-actuated clutch release bearing

· Close-ratio gearing for improved acceleration and performance

· Carbon fiber synchro rings for reduced wear and improved shifting feel

· Torsen limited-slip differential (optional on some models)

· Worn or damaged synchro rings

· Clutch wear or failure

· Gear grinding or crunching due to worn or damaged gears

· Leaks in the transmission case or clutch housing

· Short-throw shifters for improved shifting feel

· Lightweight flywheels for improved acceleration

· High-performance clutches for increased torque capacity

· Gear ratio changes for improved acceleration or top-end speed