Terra Firma Automotive supplies genuine Nissan transmission internals that restore crisp, positive gear engagement to your Z32 manual gearbox. This 3rd & 4th gear sleeve coupling is the exact OEM sliding sleeve that locks the 3rd or 4th gear to the main shaft when selected. Precision-machined with the correct spline count, engagement teeth profile, and surface treatment Nissan specified, it delivers the solid mechanical lock and smooth shifting action these transmissions are known for.

The 3rd/4th sleeve is a high-wear item because these gears see frequent use during normal driving. Over time the engagement teeth can round off or develop play, resulting in notchy shifts, grinding, or a loose feel. This authentic replacement sleeve restores tight, confident gear selection and works perfectly with the matching synchro rings and hub to reduce wear on surrounding components.

At Terra Firma Automotive we focus on providing the correct factory parts that make rebuilt transmissions feel factory fresh again. Whether you’re performing a complete gearbox overhaul on your twin-turbo, refreshing the middle gears on a naturally aspirated model, or doing a thorough synchro and sleeve service on your 1989–1996 Fairlady Z or 1990–1996 300ZX, this 3rd/4th sleeve coupling is a vital piece for achieving smooth, durable, and satisfying shifts.

 

• Genuine Nissan OEM 3rd & 4th gear sleeve coupling
• Direct fit for all Z32 manual transmissions (NA & TT)
• Precision splines and engagement teeth for positive locking
• Restores crisp, confident shifts into 3rd and 4th gear
• Reduces grinding and wear on synchro rings and gears
• Essential during 3rd/4th synchro or full transmission rebuilds
• High-quality hardened construction for long service life
• USDM 300ZX (Z32): 1990–1996 (VG30DE & VG30DETT – NA or TT)
• JDM Fairlady Z (Z32): 1989–1996 (VG30DE & VG30DETT – NA or TT)
• Engine Compatibility: Fits all VG30DE and VG30DETT engines with manual transmission