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SKU: MZ191-HCR
OS Giken MZ191-HCR Expanded Capacity Rear Differential Cover – 2016+ Mazda Miata MX-5 ND
The OS Giken MZ191-HCR Expanded Capacity Rear Differential Cover is a premium performance upgrade for the 2016+ Mazda Miata MX-5 (ND chassis). This high-capacity cover increases fluid volume for better cooling and lubrication during spirited driving, track days, or autocross. Precision-machined from high-grade aluminum with a deep finned design, it dissipates heat more effectively than stock while adding structural rigidity to the differential housing. The OS Giken cover features a magnetic drain plug to capture metal particles, a sight glass for easy fluid level checks, and a robust mounting flange with all necessary hardware for direct bolt-on installation. Perfect for street, track, or competition use where sustained high-RPM operation demands superior diff cooling and protection.
Key Features
- Expanded Fluid Capacity – Increased oil volume for superior cooling and lubrication
- Finned Aluminum Construction – Enhanced heat dissipation and added rigidity
- Magnetic Drain Plug – Captures metal particles to protect gears and bearings
- Sight Glass – Easy fluid level inspection without removal
- Direct Bolt-On Fit – Replaces factory cover using OEM mounting points
- Premium OS Giken Quality – Trusted in motorsport for reliability and performance
Specifications
| Specification | Detail |
|---|---|
| Part Number | MZ191-HCR |
| Brand | OS Giken |
| Material | High-grade aluminum alloy |
| Finish | Natural aluminum with machined fins |
| Capacity Increase | Expanded over stock (exact volume varies by application) |
| Features | Magnetic drain plug, fluid level sight glass |
| Position | Rear Differential Cover |
| Compatibility | 2016+ Mazda MX-5 Miata (ND) |
| Warranty | OS Giken Limited Warranty |
| Shipping Weight | Approx. 6.8 lbs |
Whats Included
- One OS Giken Expanded Capacity Rear Differential Cover
- Magnetic drain plug
- Fluid level sight glass
- All necessary mounting hardware and gasket
- Installation instructions
Product Notes
- Direct replacement for factory rear diff cover on ND Miata
- Increased capacity helps maintain optimal fluid temps during extended high-RPM use
- Magnetic plug and sight glass make maintenance easier and more effective
- Ideal for autocross, track days, spirited street driving, or modified power levels
Installation Notes
- Estimated time: 30-60 minutes
- Drain fluid, remove stock cover, clean mating surface, install new cover with included gasket
- Refill with recommended diff fluid (quantity increased due to extra capacity)
- Professional installation recommended if unsure
This Part Fits
| Year | Make | Model | Notes |
|---|---|---|---|
| 2016+ | Mazda | MX-5 Miata (ND) | All trims and transmissions |
Why Choose OS Giken Differential Cover?
- Expanded capacity for better cooling during demanding driving
- Premium aluminum construction with heat-dissipating fins
- Magnetic plug and sight glass for easy maintenance and protection
- OS Giken motorsport heritage – trusted in high-performance applications
Frequently Asked Questions
-
Q: Will this fit my 2020 Mazda Miata ND2?
A: Yes, direct fit for all 2016+ ND Miata models regardless of trim or transmission. -
Q: How much extra fluid capacity does it add?
A: Increased over stock (exact amount varies; typically 0.3-0.5 liters more). -
Q: Is any modification required?
A: No, bolt-on replacement using factory mounting points.
Shipping and Handling
- Method: UPS / FedEx Ground
- Availability: In stock ships same or next business day
- Packaging: Secure protective packaging
- Weight: Approx. 6.8 lbs
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