AE86 CUSCO Type RS 1.5-Way Rear Limited Slip Differential Kouki (Corolla 1986-1987)

CUSCO Type RS 1.5-Way Rear Limited Slip Differential

For Late-1985–1987 Toyota Corolla Levin / Sprinter Trueno AE86 Kouki & 1986–1987 Toyota Corolla Sport GT-S AE86 with Manual Transmission

Overview

The CUSCO Type RS 1.5-Way Limited Slip Differential is a performance-focused rear differential upgrade for the Kouki / late-model Toyota AE86. Designed for the later AE86 rear differential configuration, it improves traction by controlling the speed difference between the rear wheels and transferring power more effectively when accelerating out of corners.

CUSCO's Type RS design uses precision coil springs to generate lower initial torque than a conventional cone-spring mechanical LSD. This reduces unnecessary drivetrain resistance while providing quick, progressive lockup in response to throttle input. The result is a mechanical LSD that works well for spirited street driving, autocross, grip driving, and performance-oriented AE86 builds.

The 1.5-way configuration provides strong differential lock under acceleration with a milder locking effect during deceleration, offering a balanced setup for drivers who want predictable rear traction without the stronger off-throttle behavior of a full 2-way differential.

Key Features

• Type RS clutch-type mechanical limited slip differential
• 1.5-way rear differential configuration
• Designed specifically for Kouki / late-model AE86 rear differential applications
• Strong lockup under acceleration with reduced locking effect during deceleration
• Precision RS coil-spring design provides responsive engagement with lower initial resistance
• Helps improve rear-wheel traction during acceleration and corner exit
• Reduced clutch-plate pressure helps minimize chatter and supports consistent operation
• 55° acceleration / 20° deceleration cam-angle configuration
• 12 RS springs in the standard configuration
• Suitable for street performance, autocross, grip driving, and other performance-oriented AE86 setups

Type RS 1.5-Way Operation

A 1.5-way LSD provides its strongest locking action when power is applied through the drivetrain. This helps both rear tires contribute more effectively when accelerating, particularly when cornering or when available traction differs between the inside and outside rear wheels.

During deceleration, the differential continues to provide a milder locking effect rather than operating as aggressively as a 2-way LSD. This creates a versatile balance between acceleration traction, corner-entry behavior, and everyday drivability.

The Type RS mechanism uses coil springs between the pressure rings to maintain controlled initial torque. This design provides quick, linear response to throttle input while reducing unnecessary drag when maximum differential lock is not required.

Vehicle Fitment

Toyota Corolla Levin

• Late-1985–1987 Toyota Corolla Levin AE86 – Kouki – 4A-GE 

Toyota Sprinter Trueno

• Late-1985–1987 Toyota Sprinter Trueno AE86 – Kouki – 4A-GE 

Toyota Corolla Sport GT-S

• 1986–1987 Toyota Corolla Sport GT-S AE86 – Kouki – 4A-GE 

Fitment Notes

• Kouki / late-model AE86 application
• Japanese-market application begins approximately October 1985
• Applies after chassis 0193815 / 5066286
• Designed for the later AE86 rear differential and axle configuration
• Not interchangeable with the earlier Zenki AE86 LSD without confirming the complete axle/differential configuration
• Does not directly fit the factory North American SR5 S-series rear differential
• An SR5 requires a compatible GT-S / T-series rear axle conversion or equivalent rear differential setup before using this LSD
• Intended for manual-transmission AE86 applications
• Original differential application is the open rear differential configuration
• Differential installation requires proper ring-gear, bearing preload, and backlash setup; professional differential installation is recommended

Product Specifications

Brand: CUSCO
Series: Type RS
Product Type: Mechanical Limited Slip Differential
Position: Rear
Configuration: 1.5-Way
Drive Layout: Rear-Wheel Drive / FR
Cam Angle: 55° Acceleration / 20° Deceleration
Initial Torque: 5–7 kgf·m
RS Springs: 12 Standard / 12 Maximum
Differential Type: Clutch-Type Mechanical LSD
Standard Differential Application: Open Differential
Vehicle Configuration: Kouki / Late-Model AE86

What's Included

• (1) CUSCO Type RS 1.5-Way Rear Limited Slip Differential Assembly