🏷️ Basic Information

Make:

Subaru

Model:

Impreza WRX STI

Year:

2008

Chassis Code:

GR/GV Series (Hatchback/Sedan)

Product Type:

Service Repair Workshop Manual

👋 Introduction

Positioning:

Performance-oriented compact sedan/hatchback, rally homologation special, enthusiast vehicle

Competitors:

Mitsubishi Lancer Evolution, Subaru WRX (standard), Mitsubishi Eclipse GT, Nissan Silvia (older models)

Performance Focus:

Symmetrical All-Wheel Drive, turbocharged boxer engine, performance-tuned suspension, powerful Brembo brakes

Enthusiast Appeal:

Legendary handling, strong aftermarket support, rally heritage

📋 Manual Details

Coverage Scope:

All Models & All Repairs A-Z

Specificity:

Vehicle/Model Specific (Not Generic)

Estimated Page Count:

Over 2000 (Typical for comprehensive dealer manuals)

Type:

Workshop Manual / Service Manual

Language:

English

Format:

Digital (Likely PDF, but confirmation needed)

📖 Manual Coverage

Engine:

Complete engine mechanicals, tuning, diagnostics, removal/installation, overhaul

Drivetrain:

Manual Transmission (TY75 series), All-Wheel Drive (AWD) system, differentials (front, center, rear), driveshafts, axles

Suspension:

Front struts, rear multi-link suspension, springs, shocks, control arms, bushings, alignment specifications

Brakes:

Front Brembo 4-piston calipers, rear Brembo 2-piston calipers, brake fluid, ABS, EBD, parking brake

Electrical:

Wiring diagrams, ECU, sensors, ignition system, charging system, lighting, power accessories, diagnostics

Body And Chassis:

Body panels, doors, windows, seats, interior trim, underbody, structural components, crash repair data

Fuel System:

Fuel pump, injectors, fuel lines, evaporative emission control (EVAP)

Cooling System:

Radiator, fan, thermostat, water pump, coolant specifications

Exhaust System:

Manifold, catalytic converter, mufflers, O2 sensors

Steering:

Power steering system, steering column, wheel alignment

Maintenance:

Scheduled maintenance, oil changes, filter replacements, fluid checks and changes

Troubleshooting:

Diagnostic trouble codes (DTCs), symptom-based troubleshooting, electrical system diagnostics

Repair:

Component removal, installation, adjustment, and overhaul for all major systems

Diagnostics:

Detailed diagnostic procedures, including use of Subaru Select Monitor (SSM) or equivalent diagnostic tools

Rebuilding:

Engine rebuild procedures, transmission overhaul, differential rebuilds

Specifications:

Torque specifications, clearances, fluid capacities, electrical specifications

Depth:

Comprehensive (from basic maintenance to complete engine and transmission rebuilds)

📊 Manual Specifications

Digital Format:

Likely PDF, optimized for searchability and readability. May include interactive elements if a digital OEM version.

Print Quality:

High-resolution images, clear diagrams, and legible text suitable for printing specific sections.

Binding Type:

N/A (Digital Format)

Paper Type:

N/A (Digital Format)

⚙️ Engine Specifications

Engine Code:

EJ257

Configuration:

2.5L Turbocharged Flat-4 Boxer Engine

Bore X Stroke:

99.5 mm x 79.0 mm

Compression Ratio:

8.4:1

Redline:

7000 RPM (approx.)

Horsepower:

305 hp @ 6000 RPM (US Spec)

Torque:

290 lb-ft @ 4000 RPM (US Spec)

Fuel Delivery:

Sequential multi-port fuel injection (SFI)

Turbocharger:

IHI VF48 Twin-Scroll Turbocharger

Fuel Type:

Premium Unleaded Gasoline (91 octane or higher recommended)

🔧 Transmission

Transmission Type:

6-Speed Manual Transmission

Transmission Model:

TY756

Optional Transmission:

Not Available for WRX STI

All Wheel Drive:

Symmetrical All-Wheel Drive with Driver Controlled Center Differential (DCCD)

Differential Lock:

Mechanical Limited Slip Rear Differential (LSD), Helical Limited Slip Front Differential

📐 Dimensions

Length:

4415 mm (Hatchback) / 4580 mm (Sedan)

Width:

1795 mm

Height:

1470 mm (Hatchback) / 1440 mm (Sedan)

Wheelbase:

2650 mm

Ground Clearance:

150 mm

Curb Weight:

Approx. 1505 kg (Hatchback) / 1500 kg (Sedan)

Gross Vehicle Weight Rating:

Approx. 1920 kg

Towing Capacity:

Not Recommended

Cargo Volume Hatchback:

Approx. 300-400 liters (rear seats up, depending on configuration)

Cargo Volume Sedan:

Approx. 400-450 liters

🛡️ Safety Features

NHTSA Front Crash Test:

5-Star (Likely, based on contemporary Subaru standards)

IIHS Front Offset Crash Test:

Good (Likely, based on contemporary Subaru standards)

Traction Control:

Vehicle Dynamics Control (VDC) with AWC mode

ABS:

Anti-lock Braking System (ABS)

Ebd:

Electronic Brake-force Distribution (EBD)

AWD:

Symmetrical All-Wheel Drive

Airbags:

Front airbags, front side-impact airbags, side-curtain airbags (front and rear)

Seatbelts:

3-point front and rear seatbelts with pretensioners and force limiters

Body Structure:

Ring-shaped reinforcement frame, energy-absorbing crumple zones

💡 Technology Features

Head Unit:

Factory AM/FM/CD audio system with available navigation. Basic LCD display for climate and audio.

Cruise Control:

Standard cruise control system.

Keyless Entry:

Standard keyless entry with immobilizer.

Auxiliary Input:

Standard auxiliary audio input jack.

🔧 Maintenance

Oil Change Interval:

Every 3,750 miles or 6 months (severe driving) / 7,500 miles or 12 months (normal driving) - Consult manual for exact Subaru recommendations.

Air Filter Replacement:

Every 15,000 miles or 12 months

Cabin Air Filter Replacement:

Every 15,000 miles or 12 months

Spark Plug Replacement:

Every 30,000 miles (NGK Iridium recommended)

Coolant Replacement:

First replacement at 30,000 miles, then every 15,000 miles or 12 months thereafter.

Engine Oil Type:

SAE 5W-30 Synthetic (Subaru Extra Protect 5W-30 recommended, API SN or ILSAC GF-5)

Engine Oil Capacity:

5.8 US quarts (with filter)

Transmission Fluid Type:

Subaru Extra-S or equivalent (75W-90 GL-5 Gear Oil for front and rear differentials)

Transfer Case Fluid Type:

Subaru Extra-S or equivalent (75W-90 GL-5 Gear Oil)

Coolant Type:

Subaru Super Coolant (Blue) or equivalent ethylene glycol-based antifreeze

Brake Fluid Type:

DOT 3 or DOT 4

Engine Knock Detonation:

Susceptible to detonation on lower octane fuel or if detonation control is compromised (e.g., faulty knock sensor, boost leaks).

Ringland Failure:

Early EJ257 engines in some models were prone to ringland failure, especially if not properly maintained or if subjected to aggressive driving without adequate cooling.

Clutch Wear:

Performance-oriented clutch can wear faster with aggressive driving. Flywheel chatter is also common.

Dccd Malfunctions:

The Driver Controlled Center Differential (DCCD) system can develop electronic issues leading to an 'inoperable' state, often defaulting to a 50/50 split.

Turbo Oil Feed Line:

The banjo bolt on the turbo oil feed line can become restricted, starving the turbo of oil and leading to failure.

📚 Vehicle History

Subaru Heritage:

Japanese automotive manufacturer known for its boxer engines and Symmetrical All-Wheel Drive system. Strong ties to motorsports, particularly rallying.

Impreza Lineage:

The Impreza WRX STI is the halo performance variant of Subaru's compact Impreza line. Introduced in the 1990s, it quickly gained a reputation for its rally-bred performance and AWD capabilities.

2008 Generation Update:

The 2008 model year marked the debut of the third generation Impreza (GE/GH/GR/GV), which controversially moved away from the sedan-only platform to include a hatchback body style. The WRX STI also gained a more aggressive styling, wider track, and improved chassis rigidity.

Manufacturing Location:

Gunma Plant, Japan

🏆 Awards & Recognition

Car And Driver 10Best:

While the WRX STI itself might not have made the 10Best list in 2008, the WRX often did, indicating the platform's strong performance credentials.

Rally Championships:

The Impreza WRX STI is a direct descendant of Subaru's highly successful World Rally Championship (WRC) cars, which accumulated multiple driver and manufacturer titles.