OS SuperLock LSD for Subaru GDB(GRB) WRX STi - REAR
The OS Giken Super Lock LSD uses our patented pressure ring design that allows for smooth, progressive locking. This design is a spline-through-side-gear design that allows for fitment of more friction plates (up to 2x as many as competitors versions).
- All components are chemically heat treated for maximum durability
- All components are constructed from a high-grade steel alloy
- Gears are raw-forged for maximum strength
- Clutch disks are precision-machined simultaneously on both sides to extremely tight tolerances resulting in minimal warpage.
- LSD case is machined from a single billet piece to ensure uniformity.
The OS LSD standard spec allows for low preload while still retaining a fully progressive 100% lock capability. Operation is quiet and the progressive locking allows for smooth predictable locking. When replacing an open diff, equipping an
OS LSD will completely improve the driving experience while maintaining everyday drivability.
Subaru WRX STI (GD/GR) - EJ25
- Ramps -25/38
- Lock Timing - 336
- Total Plates - 20
- Preload - 10S
Refer to OEM Service Manual for install
If your application is making significantly more power, we offer additional tuning services to your new/used LSD in-house. More power typically means more kick to the differential. We have the ability to speed up or slow down differential action to allow the vehicle to achieve maximum traction.
- Initial torque can be adjusted by using thicker / thinner cone springs
- Lock progression timing can be adjusted by using stiffer / weaker pressure ring springs, allowing the progression of full lock to be fine-tuned to the vehicle/driver
- Ramp angles can be customized by swapping the pressure ring and iron cross for even more tuning possibilities
- TCD spec disks can be installed for increased oil cooling and even smoother operation
*Warning: This product can expose you to chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to: www.P65warnings.ca.gov/
Our revolutionary pressure ring houses our patented lock timing system, where springs work in opposition of torque being applied to the LSD. This results in a progressive, smooth, and quiet operation of the clutch discs within the differential. Furthermore, by modifying the spring rate, the rate of which the differential reaches full lock can be adjusted to suit particular vehicle settings and racing styles.
Unlike other manufacturers that utilize modular components, we produce our cams and pressure rings as matching sets. Because the faces of the cams are grounded exactly to match the application area of the pressure ring, torque transfer is smooth and consistent throughout the lock range.
The unique “spline-through” side gears allows our LSD to house more clutch discs than other competitors. Also, due to the relatively large size, it provides superior durability and torque transfer.
The discs are precision-machined simultaneously on both sides to extremely tight tolerances to reduce flatness deviations and to eliminate the need to perform the tedious “figure 8” break-in period. By using as much as twice as many clutch discs than competing brands, our differential provides superior torque hold, while also reducing the “clunkiness” of traditional clutch-type LSDs. This also results in enhanced durability and reduced wear as torque hold is spread out over a higher amount of friction surfaces.
The case and all components are constructed from a high-grade steel alloy, and then chemically heat treated for increased durability. The extra rigidity created ensures that the internal components stay within their tight tolerances, allowing the differential to function with watch-like precision.
The “Pre-Order” order option is enabled when the listed item is either temporarily out of stock, or is only available as a “built to order” item from our factory.
Once an order for a “Pre-Order” item is received, we will confirm lead-time with our Japan factory and contact you within 1-2 business days via email with current projected production lead-time information and delivery date projections. After accepted/authorized we will proceed with finalizing your order. If the quoted lead-time is not accepted, the order will be promptly cancelled and you will be refunded immediately in full.
If there is further delay after your placed order, we will contact you with an updated delivery lead-time or provide you with the option to cancel with a full refund for any unfulfilled order items.
While there is no risk in ordering “Pre-Order” items through our website, feel free to contact us ahead of time regarding product leadtime.