OS Giken Superlock LSD

OS Giken is a Japanese manufacturer specialising in high-performance limited-slip differentials, and their Superlock range is what we recommend as the go-to upgrade across most of the BMW, Toyota, Porsche and Mercedes differentials we service.

How it works

A conventional plate-type LSD relies on a fixed set of clutch plates compressed by springs, which gives a fairly abrupt, all-or-nothing lockup and a noticeable break-in period. OS Giken's Superlock design takes a different approach: a patented Lock Timing Control System (L.T.C.S.) uses a spring built into the pressure ring itself, so the unit behaves like an open differential during gentle driving and low-load cornering, then locks up smoothly and progressively as drive torque increases under acceleration.

The Superlock design also uses a spline-through side gear (S.T.S.G.) arrangement, which allows significantly more clutch plates to be packed into a smaller side gear and pinion gear diameter than a traditional LSD. More plates spread the load across a larger surface area, which is what allows these units to reach full (100%) lock without the heat build-up, plate wear, or gradual loss of lockup that conventional units suffer over time.

Why we recommend them

• Smooth, quiet, progressive lockup with no harsh engagement
• No break-in period required
• Minimal heat generation even under sustained track use
• Long service life, with simple, inexpensive rebuilds when they are eventually needed
• Consistent, predictable behaviour that makes them easy to drive on the road and on track

Have a question about which OS Giken Superlock suits your car, or want a build for a vehicle not listed in our shop? Get in touch.