Parts

Drivetrain & differentials

The Shakewell Racing WRX STI up on stands with a wheel off at the Snowy River Sprint
Betsy on stands at Snowy River — hub and driveline exposed with the wheel off.

Gravel rallying is won and lost on traction out of slow corners, which makes the differentials the single most consequential thing you can change on a Subaru. An open or worn centre and rear will spin an inside wheel for the whole exit; a plated LSD will drag the car straight and reward throttle earlier. Gearbox and driveshaft choices follow from the same problem — the shock loads that break things are almost always a wheel unloading and re-gripping.

Drivetrain & Clutch Parts by car

GD Impreza WRX / STI 37GG Impreza WRX wagon 37GR-GV Impreza WRX STI 33VA WRX / STI 24VB WRX 11SF-SG Forester 12

What actually decides it

  • Ramp angles matter more than brand. A 1-way front locks on power only and leaves the car turning in; a 1.5-way adds some locking on the overrun, which settles the rear but pushes the nose wide if you overdo it.
  • A plated LSD needs the right friction-modifier-free oil and a bedding-in period. Running the wrong oil is the most common reason a new diff feels like nothing changed.
  • Match the diff to the housing before you order. Subaru used R160, R180 and R200 rear housings across the same era of car.

In this category

CuscoOn our cars

Cusco MZ front limited-slip differential, 1-way

The plated front diff in Betsy's stock six-speed, set 1-way so it locks on power and lets the car turn.

CuscoOn our cars

Cusco MZ rear limited-slip differential, 1.5-way

Fitted into Betsy's standard R180 rear housing, set 1.5-way for some locking on the overrun.

SubaruOn our cars

Subaru STI six-speed gearbox

The six-speed that went into the wagon for its ARC debut, with fresh front and rear diffs.

Full catalogue in this category

114 products — page 1 of 2. Every one has its own page with fitment, part numbers and photos.

Showing products 1 onward.

Before you buy

Longer guides on the things that are expensive to get wrong in this category.

All categoriesBuyer’s guides