Cusco Type MZ Rear LSDFOR Subaru WRX STI (R180 Differential 1997-2021)

The Cusco Type-MZ Limited Slip Differential (LSD 182 A) is a high-performance, mechanical rear differential specifically engineered for Subaru vehicles equipped with the heavy-duty R180 rear differential housing.

The "A" designation at the end of the base part number (LSD 182) typically indicates the 1-Way configuration (which activates exclusively under acceleration), though the housing cam can often be adjusted to a 2-Way orientation depending on setup choice.

Comprehensive Vehicle Compatibility List

This exact rear differential unit fits the following Subaru platforms:

Subaru Impreza WRX STI (GC8 Generation — Applied D to G: 1997–2000)
- Note: Fits STI Version 3, 4, 5, and 6 models featuring the Driver's Controlled Center Differential (DCCD) and standard mechanical R180 rear differentials.
Subaru Impreza WRX STI (GDB Generation: 2000–2007)
- Fits both "Bug-eye", "Blob-eye", and "Hawk-eye" STI models utilizing EJ207 or EJ257 engines.
Subaru Impreza / WRX STI Hatchback & Sedan (GRB / GVB Generations: 2008–2014)
Subaru WRX STI (VAB Generation: 2015–2021)
Subaru Forester STI (SG9 Generation: 2004–2007)
- Specifically the 6-speed manual turbo configurations equipped with the factory R180 rear axle setup.

Critical Fitment Specifications

Differential Position: Rear Axle Only.
Housing Requirement: Fits vehicles with a factory R180 differential casing. It will not fit standard WRX models that utilize the smaller R160 rear differential unless you have converted the rear subframe, axles, and hubs to STI

Visual Features to Note:

The Outer Casing (Chromoly Steel Case): The main solid, machined component featuring heavy-duty bolting flanges. This slips directly inside your Subaru's R180 rear differential carrier housing.
Type-MZ Internal Mechanism: Unlike the "Type-RS" which uses internal coil springs, the Type-MZ relies on high-tension cone springs (Cone Plates). This layout places the clutch discs under high initial tension, creating the highly responsive, aggressive locking required for race track driving.
The Cam Rings / Pressure Rings: Inside the center windows, you can see the machined diamond-shaped ramps. When you accelerate, the internal cross-pins push outward against these ramps, locking the clutch packs.