🏷️ Basic Information

Make:

Subaru

Model:

Impreza

Trim:

STI

Year:

2008

Generation:

Third Generation (GR/GV/GH/GE)

Chassis Code:

GR (Hatchback)

👋 Introduction

Market Position:

Performance compact sedan/hatchback, positioned as a rally-inspired, all-wheel-drive performance vehicle.

Competitive Analysis:

Competes with vehicles like the Mitsubishi Lancer Evolution, Volkswagen Golf GTI, Mazdaspeed3, and Ford Focus RS in its segment.

Key Features:

Symmetrical All-Wheel Drive, turbocharged Boxer engine, performance-tuned suspension, aggressive styling, advanced driver-controlled center differential (DCCD).

📋 Manual Details

Coverage Areas:

Complete workshop service and repair

Page Count:

Extensive (typical for a full workshop manual, estimated 1500-2500+ pages)

Manual Type:

Workshop Service Repair Manual

Language:

English

Format:

Digital (Instant Download, likely PDF)

📖 Manual Coverage

Systems Covered:

Engine, Drivetrain (Manual Transmission, AWD System), Suspension, Steering, Brakes, Fuel System, Exhaust System, Cooling System, Electrical System (ECU, Wiring Diagrams), HVAC, Body & Interior, Diagnostic Procedures, Emissiions Control.

Engine Mechanical:

Engine assembly, cylinder heads, pistons, crankshaft, camshafts, valve train, timing belt/chain, lubrication system, oil pump, oil pan, engine mounts.

Engine Electrical:

Ignition system, fuel injection system, sensors (MAF, MAP, O2, crank, cam), starter, alternator, ECU, emissions control system, wiring harnesses, diagnostic connectors (OBD-II).

Transmission Drivetrain:

Manual transmission service and repair, clutch system, DCCD operation and repair, propeller shaft, front and rear differentials, axle shafts.

Suspension Steering:

Front and rear suspension components (struts, shocks, control arms, bushings), power steering system (rack and pinion), wheel alignment specifications.

Brakes:

Front and rear disc brake systems, ABS system components, parking brake, brake fluid specifications and bleeding procedures.

Cooling Exhaust:

Radiator, cooling fan, water pump, thermostat, heater core, exhaust manifold, catalytic converter, muffler, emissions components.

Body Interior:

Body panels, doors, hood, trunk, interior trim, seats, dashboard, airbags, body repair procedures, glass replacement.

Procedures Included:

Scheduled Maintenance, Routine Inspections, Troubleshooting Guides, Diagnostic Trouble Codes (DTCs), Engine Overhaul, Transmission Rebuild, Brake Service, Suspension Component Replacement, Electrical Diagnosis and Repair, Bodywork Repair, Climate Control System Servicing, Clutch Replacement, Turbocharger Servicing, Differential Maintenance.

Engine Repair:

Complete engine rebuild procedures, piston and ring replacement, bearing replacement, cylinder head gasket replacement, turbocharger inspection and replacement.

Transmission Repair:

Transmission disassembly and reassembly, gear synchro replacement, clutch assembly service, DCCD system calibration.

Electrical Diagnostics:

Detailed wiring diagrams for all systems, troubleshooting flowcharts for electrical faults, sensor testing, ECU diagnosis.

Chassis Component Replacement:

Strut replacement, control arm bush replacement, wheel bearing replacement, ball joint replacement.

HVAC Service:

Refrigerant system diagnosis and repair, blower motor replacement, heater core replacement, AC system servicing.

Troubleshooting Guides:

Comprehensive symptom-based troubleshooting charts for common drivability and electrical issues.

Technical Depth:

Comprehensive: Covers basic maintenance, diagnostics, troubleshooting, component-level repair, and complete system overhauls, suitable for professional technicians and advanced DIY enthusiasts.

Torque Specifications:

Detailed torque specifications for all critical fasteners.

Diagnostic Procedures:

Step-by-step diagnostic procedures for common and complex faults, including live data analysis guidance.

Rebuild Procedures:

Full engine and transmission rebuild instructions with exploded views and component identification.

Emissions Testing:

Information on emissions control systems and related testing procedures.

📊 Manual Specifications

File Format:

PDF (Searchable, Printable)

Print Quality:

High Resolution (ensuring clarity of diagrams and text)

Binding Type:

N/A (Digital Format)

Paper Type:

N/A (Digital Format)

⚙️ Engine Specifications

Engine Code:

EJ257

Engine Type:

2.5L DOHC turbocharged Boxer-4

Horsepower Est:

305 hp @ 6000 rpm

Torque Est:

290 lb-ft @ 3000 rpm

Fuel System:

Multi-point Fuel Injection (MPI) with Sequential Electronic Control

Recommended Fuel:

Premium Unleaded (91 octane or higher)

🔧 Transmission

Transmission Type:

6-Speed Manual Transmission

Transmission Type:

None for STI

Drivetrain:

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

Differential Types:

Helical limited-slip front differential, Viscous coupling center differential, Torsen limited-slip rear differential.

📐 Dimensions

Length In:

173.8

Width In:

70.1

Height In:

57.7 (Hatchback)

Wheelbase In:

103.2

Cargo Volume Cu Ft:

19.0 (Hatchback, with rear seats up)

Curb Weight Lbs:

3373

Gross Vehicle Weight Rating Lbs:

4560

🛡️ Safety Features

NHTSA Front Crash Rating:

5-Star

NHTSA Side Crash Rating:

4-Star

IIHS Front Crash Rating:

Good

IIHS Side Impact Rating:

Good

Active Safety Features:

ABS with Electronic Brake-force Distribution (EBD), Brake Assist, Traction Control System (TCS), Vehicle Dynamics Control (VDC), Subaru Advanced Vehicle Handling System.

Passive Safety Features:

Front dual-stage airbags, front side-impact airbags, side curtain airbags (for front and rear occupants), front seatbelt pretensioners with load limiters, LATCH child seat anchor system.

💡 Technology Features

Infotainment System:

Standard Subaru audio system with CD player, MP3 capability, auxiliary input jack. Optional navigation system available.

Driver Assistance:

Vehicle Dynamics Control (VDC), Traction Control System (TCS), ABS with EBD, Brake Assist.

Connectivity Features:

Auxiliary audio input jack, optional Bluetooth hands-free phone system.

🔧 Maintenance

Oil Change Interval:

Every 3,750 miles or 6 months, whichever comes first (severe duty), or 7,500 miles or 12 months (normal duty), consult manual for specifics.

Air Filter Replacement:

Every 15,000 miles or 12 months, inspect more frequently.

Spark Plug Replacement:

Every 30,000 miles (iridium type).

Engine Oil Type:

SAE 5W-30 (API SN or higher, ILSAC GF-5 or higher)

Coolant Type:

Subaru Super Coolant (Blue) or equivalent P-HOAT type antifreeze/coolant.

Transmission Fluid Type:

Subaru Extra Synchro Shift MT (for manual transmission)

Differential Fluid Type:

Subaru Hypoid Gear Oil API GL-5 (front and rear, check manual for specific viscosities)

Known Issues:

Piston ring land failure (especially on early EJ257 engines in some models/years), head gasket issues (less common than previous generations but still a potential concern), turbocharger wear, clutch wear due to performance driving, differential issues (less frequent).

Maintenance Recommendations:

Strict adherence to oil change intervals with quality synthetic oil, using a high-quality air filter, and proper engine break-in procedures for new engines or rebuilds is crucial to mitigate common issues.

📚 Vehicle History

Brand Heritage:

Subaru, a division of Subaru Corporation (formerly Fuji Heavy Industries), has a strong heritage in aviation and engineering, known for its horizontally-opposed ('Boxer') engines and Symmetrical All-Wheel Drive system.

Model Evolution:

The Impreza WRX STI is the halo performance model of the Impreza line, directly inspired by Subaru's World Rally Championship (WRC) success. The 2008 model introduced the GR chassis, marking a significant shift with the adoption of a hatchback body style for the STI in most markets.

Production Period:

2008-2014 (Third Generation)

Manufacturing Location:

Japan (Ota, Gunma Prefecture)

🏆 Awards & Recognition

Recognitions:

Consistently praised by automotive journalists for its handling, all-wheel-drive capability, and rally-bred performance. Named to Car and Driver's '10Best' lists in previous generations, though the 2008 model's specific awards vary.

Ratings:

Often rated highly for performance and all-weather capability within its class.