OS Giken Super Lock LSD – Nissan 350Z (Z33) / 370Z (Z34) | Patented Pressure Ring Design | Up to 2x More Friction Plates | Japan-Made

The OS Giken Super Lock LSD for the Nissan 350Z (Z33) and 370Z (Z34) is one of the most technically advanced and highly regarded limited-slip differentials available for the Z-car platform — featuring OS Giken's patented pressure ring design, spline-through-side-gear construction, and a billet-machined LSD case that allows for up to twice as many friction plates as competing designs. The result is a smooth, progressive, fully capable 100% locking LSD that completely transforms the 350Z and 370Z's rear axle performance while maintaining everyday street drivability. OS Giken is one of the most respected drivetrain and engine component manufacturers in Japanese motorsport — a company with decades of experience supplying precision drivetrain components to professional racing teams and serious performance enthusiasts across Japan and internationally.

Key Features:

• Patented pressure ring design — OS Giken's patented pressure ring design allows for smooth, progressive locking action — the pressure ring engages the clutch pack progressively as torque differential increases, providing controlled and predictable LSD behaviour
• Spline-through-side-gear design — OS Giken's spline-through-side-gear construction allows for fitment of up to 2x as many friction plates as competing LSD designs — more friction surface area for more effective torque transfer and greater LSD durability under sustained high-load use
• 100% progressive lock capability — the OS Giken Super Lock achieves full 100% locking capability through progressive clutch engagement — not a sudden, binary lock, but a smooth, controlled progression to full lock that is predictable and manageable on both street and track
• Low preload standard spec — the standard OS Giken LSD specification uses low preload — quiet operation and smooth, progressive locking that maintains everyday street drivability without the harshness or noise associated with high-preload LSDs
• Billet-machined LSD case — the LSD case is machined from a single billet piece to ensure uniformity, dimensional accuracy, and maximum strength — no casting porosity or dimensional variation
• Raw-forged gears — gears are raw-forged for maximum strength — forged gears have superior grain structure and fatigue resistance compared to machined-from-billet or cast alternatives
• Chemically heat treated components — all components are chemically heat treated for maximum durability — correct hardness and wear resistance for sustained high-load LSD use
• High-grade steel alloy construction — all components are constructed from a high-grade steel alloy — correct material specification for the thermal and mechanical demands of a performance LSD
• Precision-machined clutch discs — clutch discs are precision-machined simultaneously on both sides to extremely tight tolerances — minimal warpage for consistent clutch pack engagement and long-term LSD performance
• Japan-made — manufactured in Japan by OS Giken to their exacting motorsport quality standards

OS Giken Pressure Ring Design — Why It's Different:

Most clutch-type LSDs use a conventional cam-and-ramp design to engage the clutch pack — the side gears push against ramp surfaces that compress the clutch pack as torque differential increases. OS Giken's patented pressure ring design replaces the conventional cam-and-ramp with a pressure ring that engages the clutch pack more uniformly and progressively. The pressure ring design distributes the engagement force more evenly across the clutch pack — reducing clutch disc warpage, improving engagement consistency, and allowing for a smoother, more progressive locking action than conventional cam-and-ramp designs. Combined with the spline-through-side-gear construction that allows for up to 2x more friction plates, the OS Giken Super Lock's clutch pack has significantly more friction surface area than competing designs — more effective torque transfer and greater durability under sustained high-load use.

350Z / 370Z — Why an LSD Transforms the Platform:

The Nissan 350Z (Z33) and 370Z (Z34) are rear-wheel-drive sports cars with the VQ35DE/HR and VQ37VHR V6 engines respectively — powerful, rear-wheel-drive platforms that are highly sensitive to rear differential performance. The factory Nissan Torsen LSD (where fitted) or open differential limits the Z-car's ability to put power down effectively on corner exit — particularly under the high torque loads of the VQ35HR and VQ37VHR. The OS Giken Super Lock LSD's progressive 100% locking capability transforms the 350Z and 370Z's corner exit behaviour — transferring torque to the rear wheel with traction rather than the spinning wheel, allowing the car to drive out of corners with significantly more rear traction and more predictable, controllable chassis behaviour. The result is a completely improved driving experience on both street and track.

Specifications:

• Brand: OS Giken
• Part Number: osgNS111-HA
• Barcode: NS111-HA
• Type: Clutch-type LSD (Super Lock) — patented pressure ring design
• Friction Plates: Up to 2x more than competing designs
• Lock Capability: 100% progressive
• Case: Single billet-machined
• Gears: Raw-forged
• Heat Treatment: Chemical heat treatment on all components
• Application: Nissan 350Z (Z33) / Nissan 370Z (Z34)
• Origin: Japan

Fitment Information:

• Nissan 350Z — Z33 chassis — VQ35DE / VQ35HR — all variants
• Nissan 370Z — Z34 chassis — VQ37VHR — all variants
• Note: Professional installation by an experienced drivetrain specialist strongly recommended. A break-in procedure is required after installation. Use the correct OS Giken-specified differential fluid — incorrect fluid will damage the clutch pack. Verify your specific 350Z or 370Z variant before ordering.

What's Included:

• OS Giken Super Lock LSD unit — Nissan 350Z / 370Z (osgNS111-HA)
• Refer to OS Giken's product documentation for complete kit contents, installation specifications, fluid specification, and break-in procedure

Installation Notes:

• Professional installation by an experienced drivetrain specialist strongly recommended — LSD installation requires correct differential disassembly, correct clutch pack preload setting, correct ring and pinion backlash adjustment, and correct bearing preload
• Use the correct differential fluid specification for the OS Giken Super Lock LSD — clutch-type LSDs require a specific friction modifier content in the differential fluid — using the wrong fluid will cause clutch pack wear and incorrect LSD behaviour. Refer to OS Giken's fluid specification for this unit.
• A break-in procedure is required after installation — follow OS Giken's break-in procedure to correctly seat the clutch plates before subjecting the LSD to full-load use
• Change the differential fluid after the break-in period — the initial fluid change after break-in removes clutch plate material deposited during the break-in process
• Verify correct LSD function after installation — the LSD should engage progressively and smoothly under load — any grinding, chattering, or binding indicates incorrect installation or incorrect fluid specification

Why OS Giken?

OS Giken is one of the most respected drivetrain and engine component manufacturers in Japanese motorsport — a company with decades of experience supplying precision drivetrain components to professional racing teams and serious performance enthusiasts across Japan and internationally. OS Giken's Super Lock LSD is their flagship limited-slip differential design — a patented pressure ring clutch-type LSD that has been proven in Japanese touring car racing, time attack, and circuit competition across multiple platforms. For 350Z and 370Z owners who want the most technically advanced, motorsport-proven LSD available for the Z-car platform, OS Giken Super Lock is the definitive choice.

Perfect For:

• Nissan 350Z (Z33) and 370Z (Z34) owners who want the most premium, technically advanced LSD upgrade available — OS Giken's patented pressure ring Super Lock for smooth, progressive 100% locking capability and transformed rear axle performance
• Z-car track day and time attack builds where rear axle traction, corner exit performance, and chassis balance are critical for lap time and driving confidence
• Street-driven 350Z and 370Z owners who want a performance LSD that completely improves the driving experience while maintaining everyday drivability — the OS Giken's low preload standard spec and progressive locking action make it equally suitable for street and track use
• Serious Z-car performance builds where OS Giken's motorsport credentials, patented pressure ring design, and Japan-made quality are the correct choice for a critical drivetrain component

Note: Professional drivetrain specialist installation required. Use correct OS Giken-specified differential fluid — incorrect fluid will damage clutch pack. Break-in procedure required after installation. Change fluid after break-in period. Verify 350Z or 370Z variant before ordering.