Do you ship to all countries within Europe?
Yes, we ship to both retail customers and B2B partners across Europe. Since our products are dispatched from our European warehouse, EU customers benefit from fast transit times and will not face any unexpected customs duties, import taxes, or clearing fees.
Are all products on this website genuine OS Giken Japan parts?
Absolutely. OSGiken.eu is the official distribution partner for the European market. Every single product we supply is 100% authentic, sourced directly from the OS Giken factory in Okayama, Japan, and comes with full factory warranty support.
What makes the OS Giken Super Lock LSD superior to standard plate-style LSDs?
Traditional limited-slip differentials can sometimes be noisy or lock abruptly in tight corners. OS Giken’s patented design allows for up to twice as many friction plates as competing brands. This creates a 100% progressive, linear lock that provides unparalleled traction on the track while remaining whisper-quiet during daily street driving.
Is the superlock a clutch type LSD?
Yes, the superlock and TCD LSD's are all clutch type lsd's.
But due to evolutions in the design these LSD have an extra tuning possibilty and very low maintenance (only oil)
Is there a break-in procedure for the OS Giken LSD?
Yes. To ensure optimal longevity, we recommend a 1,000 km break-in period of street driving.
For our motorsport customers we recommend to do 1 full day at the track or course.
After this period, you must change the differential fluid to flush out any initial wear particles and refresh the oil after the extra heat buildup due to break-in.
What oil is recommended for OS Giken differentials
That depends on the application:
- Transaxle (Fwd cars, porsche, gearbox and differential is 1 part) OEM recommended oil of OS Giken 7.2 oil.
- Differentials: OS250R oil.
What is the difference between the Grand Touring, STR, and Racing Multi-Plate clutches?
The right choice depends entirely on your horsepower goals and how you use the car:Grand Touring (GT Series): Perfect for high-horsepower street cars and occasional track days. It features a lighter pedal effort and a smooth engagement point.STR Series: Designed for sporty street use and regular track days. A great middle-ground balancing motorsport performance with daily drivability.Racing Multi-Plate (Twin/Triple/Quad): Purely built for competitive motorsport (drift, drag, time attack). Engineered to hold extreme torque ($1000+\text{ Nm}$) with a very direct, aggressive engagement.
Are OS Giken clutch kits supplied with a flywheel?
Yes, virtually all of our multi-plate clutch assemblies (Twin, Triple, Quad, and STR) are sold as a complete matched system. This includes the clutch discs, pressure plate, and a lightweight chrome-moly steel flywheel.
I cannot find my specific vehicle model on your website. Can you still help?
OS Giken has a massive catalog covering Japanese (JDM), European, and legendary classic sports cars. If your vehicle is not listed in our webshop, please contact our support team. We can often special-order the correct application directly from Japan for you.
What is included in an OS Giken Close-Ratio Gear Kit?
Our close-ratio gear kits are designed to optimize your car’s powerband by eliminating the dramatic RPM drops found in OEM gear ratios. Depending on the specific vehicle application, kits typically include heavy-duty input shafts, upgraded main shafts, and specific gear sets. Please note that these kits are designed to be installed inside your original OEM gearbox casing.
Can the OS-88 6-Speed Sequential Transmission handle high-horsepower street use?
While the legendary OS-88 Sequential Gearbox is capable of holding immense power (rated up to $1500\text{ hp}$ for specific applications), it is a dog-engagement motorsport transmission. It requires precise, aggressive shifting and regular maintenance intervals. Because dog-box transmissions do not use synchronizers, they are loud and heavily compromised for regular street driving; they are best suited for dedicated track, drag, and drift cars.
How can I apply to become an official OS Giken dealer in Europe?
We are always looking to expand our network of professional tuners, race shops, and parts distributors across Europe. To apply, please just send us an e-mail with your application.