Driveshaft Shop 510274 Direct Fit 800HP Rear Axle for 2009-2018 Subaru STI

Vehicle Fitment

• 2009-2017 Subaru Impreza WRX STI (GRB Hatchback), 2.5L EJ257, AWD -- Rear
• 2009-2014 Subaru Impreza WRX STI (GVB Sedan), 2.5L EJ257, AWD -- Rear
• 2015-2017 Subaru WRX STI (VAB Sedan), 2.5L EJ257, AWD -- Rear

Fitment Notes

• Rear axle only -- interchangeable left or right (single unit fits either side)
• Direct bolt-in -- uses OEM spline count and hub interface, no hub modification required
• Sold individually -- order 2 for a complete rear axle set
• HP rating: 700-1000 WHP depending on application and launch conditions
• Wheel studs, bearings, and seals not included

Features

• X4 rated -- DSS's highest direct-fit performance level for street and track use
• 300M chromoly bar -- the strongest bar material DSS uses in production axles
• Billet chromoly outer CV housing -- eliminates cracking and failure at the outer CV under high-power launches
• Ball and cage inner CV -- updated from prior tripod design for increased strength and articulation angle
• Larger radius spline plug at inner CV -- additional strength under high torsional load
• OEM spline size retained -- direct bolt-in, no custom hubs or adapters required
• Engineered for drag, road course, autocross, and rally applications

Specifications

• Part Number: 510274 (RA8530X4-V2)
• Series: X4 Rated
• Position: Rear -- interchangeable left or right
• Bar material: 300M chromoly
• Outer CV housing: Billet chromoly
• Inner CV type: Ball and cage
• HP rating: 700-1000 WHP
• Spline: OEM size
• Wheel studs included: No
• Bearings included: No
• Seals included: No
• Quantity: Sold individually

Included Components

• 1x X4 rated rear axle shaft assembly

Product Description

The Driveshaft Shop 510274 (RA8530X4-V2) is a single X4 rated rear axle for the 2009-2017 Subaru WRX STI, interchangeable between the left and right sides. It is a direct bolt-in replacement using the factory spline count and hub interface -- no custom hubs, adapters, or machining required. The X4 rating is DSS's highest direct-fit performance tier, designed for STI builds running 700-1000 WHP on the street and track across drag, road course, autocross, and rally applications.

The axle is built around a 300M chromoly bar -- the strongest bar material in DSS's production lineup -- paired with a billet chromoly outer CV housing that eliminates the cracking and catastrophic outer CV failure common on high-power STI launches. The inner CV has been updated from the prior tripod design to a full ball and cage unit with a larger radius spline plug, increasing torsional strength and articulation capability. Wheel studs, bearings, and seals are not included. Order two for a complete rear axle set. Backed by The Driveshaft Shop's manufacturer warranty.