OS Giken 04/99 - 04/04 Honda S2000 / 04-05 Mazda Miata (MT Only) Super Lock LSD OS Giken OSGHA091-HA
OS Giken 04/99 - 04/04 Honda S2000 / 04-05 Mazda Miata (MT Only) Super Lock LSD OS Giken OSGHA091-HA
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OS Giken 04/99 - 04/04 Honda S2000 / 04-05 Mazda Miata (MT Only) Super Lock LSD

OS Giken
OSGHA091-HA
Differentials
9 Units In Stock - Ships Next Business Day
$ 1,450.00
$ 1,450.00

SKU: HA091-HA

OS Giken 1999-2004 Honda S2000 / 2004-2005 Mazda Miata (MT Only) Super Lock LSD

The OS Giken Super Lock LSD (HA091-HA) is a clutch-type limited slip differential that replaces the stock open diff in 1999-2004 Honda S2000 and 2004-2005 Mazda Miata manual transmission models. This direct-fit unit locks both acceleration and deceleration for consistent power delivery to both wheels. Drivers gain superior corner exit speed and stability in drift racing or autocross.

Key Features

  • Clutch-Type Design: 6-plate clutch pack with high initial torque (70-120 Nm) engages instantly for full power transfer under load
  • Forged Gears: 4340 chrome-moly steel side and pinion gears resist shock loads and wear in high-horsepower builds
  • Super Lock Ramp Angles: Aggressive 50-degree accel and 45-degree decel angles provide 100 percent lock ratio for maximum grip
  • 2-Way Operation: Locks on throttle on and off for drift control and rally-style traction
  • Maintenance-Free: Sealed design with lifetime clutch durability under proper oil use

Product Notes

  • Manual transmission only, not compatible with automatics
  • Requires OS Giken LS gear oil or equivalent GL-5 75W-90 synthetic
  • Ships in protective crate, handling fee may apply for heavy item

Installation Notes

  • Professional installation recommended.
  • Drain stock differential fluid completely before install
  • Direct bolt-in replacement, uses OEM mounting hardware

This Part Fits

Year Make Model Submodel
1999-2004 Honda S2000 Base
2004-2005 Mazda Miata Mazdaspeed

Why Choose OS Giken?

  • Proven in D1 Grand Prix drifting and Super GT racing
  • Hand-assembled in Japan with tight tolerances
  • Engineered for 500+ HP applications without failure

Frequently Asked Questions

  • Q: Will this fit 1999-2004 Honda S2000 with stock differential?
    A: Yes, HA091-HA is a direct replacement for AP1 S2000 MT models worldwide
  • Q: What materials are used in construction?
    A: Forged 4340 steel gears, high-capacity steel clutch plates, and aluminum housing
  • Q: What is the warranty and break-in procedure?
    A: 1-year manufacturer warranty, initial 500-mile break-in with light driving and fluid change

Shipping & Handling

  • Method: UPS Ground or FedEx Ground
  • Availability: In stock - ships same or next business day
  • Packaging: Secure wooden crate 15x15x15 inches
  • Weight: 48 lbs (21.8 kg)

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