🏷️ Basic Information

Make:

Subaru

Model:

Impreza WRX STI

Year:

2005

Chassis Code:

GDB (Widebody)

Platform:

Subaru Global Platform (though this is technically the GC/GD generation transition year)

👋 Introduction

Segment:

Performance Compact Sedan/Wagon

Usp:

All-Wheel Drive, Turbocharged Boxer Engine, Rally Pedigree, Driver Engagement

Competitors:

Mitsubishi Lancer Evolution, Subaru WRX (non-STI variants), Ford Focus RS, Honda Civic Type R (later generations)

Sti Features:

Driver-controlled center differential (DCCD), Twin-scroll turbocharger (EJ207), Brembo brakes, STI-tuned suspension, Hood scoop, Rear spoiler, Recaro seats

Wrx Features:

Turbocharged boxer engine (EJ205/EJ255 depending on market), Symmetrical All-Wheel Drive, Sport-tuned suspension

Non Turbo Features:

Naturally aspirated boxer engine, All-Wheel Drive (standard on most markets), Practicality

📋 Manual Details

Engine Variants:

Turbocharged EJ207/EJ257, Naturally Aspirated EJ20

Transmission Variants:

6-speed manual (STI), 5-speed manual (WRX/non-turbo), 4-speed automatic (non-turbo)

Regions Covered:

Global specifications with potential regional variations noted

Estimated Pages:

Hundreds (exact count not provided, but indicative of comprehensive coverage)

Type:

Service Repair Manual

Language:

English

Format:

PDF

📖 Manual Coverage

Powertrain:

Engine Mechanical (EJ20, EJ207, EJ257), Engine Control System (ECU, sensors, actuators), Fuel System, Ignition System, Exhaust System, Turbocharger System, Drivetrain (All-Wheel Drive, Center Differential, Rear Differential)

Transmission:

Manual Transmission (6-speed DCCD, 5-speed), Automatic Transmission (4-speed), Clutch System, Driveshafts, Axles

Chassis:

Suspension (Front MacPherson Strut, Rear Multi-link), Steering System (Power Steering), Brakes (ABS, Disc Brakes), Wheels, Tires

Electrical:

Wiring Diagrams, Battery, Charging System, Starting System, Lighting System, Instrumentation, Power Accessories, Audio System, Immobilizer

Bodywork:

Exterior Panels, Doors, Hood, Trunk, Bumpers, Glass, Interior Trim, Seats, Airbags

HVAC:

Air Conditioning, Heating, Ventilation

Maintenance:

Oil Changes, Filter Replacements, Spark Plug Service, Coolant Flushes, Belt Inspections/Replacement, Brake Fluid Service, Differential Fluid Service, Transmission Fluid Service

Repair:

Engine Overhaul (Top End, Bottom End), Turbocharger Rebuild/Replacement, Transmission Rebuild, Clutch Replacement, Suspension Component Replacement, Brake Caliper Rebuild/Replacement, Electrical Component Diagnosis and Repair, Body Panel Repair/Replacement

Troubleshooting:

Diagnostic Trouble Codes (DTCs), Symptom-based diagnostics, Electrical System Fault Finding, Mechanical System Diagnosis

Rebuilding:

Engine component specifications and tolerances, Transmission gear assembly, Differential unit overhauls

Refurbishing:

Interior detailing, Exterior trim restoration, Underbody rust prevention

Depth:

Comprehensive: Covers basic maintenance to full engine and transmission rebuilds, including detailed diagnostics and component specifications.

📊 Manual Specifications

Quality:

High-resolution scans, likely searchable text within the PDF (depending on original source quality)

Searchability:

Likely high due to PDF format, enabling quick access to specific topics

Output:

Printable at home or professional print shop

Digital Format:

N/A (Digital PDF)

Digital Format:

N/A (Digital PDF)

⚙️ Engine Specifications

Engine Code:

EJ207 (JDM) or EJ257 (USDM)

Type:

Horizontally-opposed (Boxer) 4-cylinder, turbocharged, intercooled

Displacement Jdm:

1994 cc

Displacement Usdm:

2457 cc

Bore Jdm:

92.0 mm

Stroke Jdm:

75.0 mm

Bore Usdm:

99.5 mm

Stroke Usdm:

79.0 mm

Compression Ratio Jdm:

8.0:1

Compression Ratio Usdm:

8.4:1

Horsepower Jdm:

280 PS (276 hp) @ 6400 rpm (JDM 'gentleman's agreement')

Horsepower Usdm:

300 hp @ 6000 rpm

Torque Jdm:

333 Nm (246 lb-ft) @ 4400 rpm

Torque Usdm:

300 lb-ft @ 4000 rpm

Fuel System:

Multi-point Fuel Injection (MPI), Sequential Electronic Fuel Injection (SEFI)

Turbocharger:

Twin-scroll IHI VF37 (JDM), Single-scroll Garrett GT30R based (USDM)

Ignition System:

Distributorless Electronic Ignition (Coil-on-plug)

Engine Code:

EJ205 (USDM/ROW), EJ255 (USDM 2006+ equivalent often found in late GD models)

Type:

Horizontally-opposed (Boxer) 4-cylinder, turbocharged, intercooled

Displacement Usdm Ej205:

1994 cc

Horsepower Usdm Ej205:

227 hp @ 5600 rpm

Torque Usdm Ej205:

217 lb-ft @ 3000 rpm

Engine Code:

EJ20 (various configurations)

Type:

Horizontally-opposed (Boxer) 4-cylinder, naturally aspirated

Displacement:

~2.0 Liters

Horsepower:

Approx. 150-170 hp (market dependent)

Torque:

Approx. 145-160 lb-ft

🔧 Transmission

Type:

6-speed manual with Driver Controlled Center Differential (DCCD)

Dccd Modes:

Auto, Manual (Locking)

Final Drive Ratio:

3.545:1 (typical)

Type:

5-speed manual

Final Drive Ratio:

4.111:1 (typical)

Type:

5-speed manual or 4-speed automatic

Final Drive Ratio:

4.111:1 (manual), 3.900:1 (automatic, typical)

Type:

Hydraulically operated, single-plate dry clutch (all variants)

Sti Manual Fluid:

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

Wrx Manual Fluid:

Subaru Gear Oil (or equivalent API GL-5, SAE 75W-90)

Automatic Transmission Fluid:

Subaru ATF-HP (or equivalent Dexron III/Mercon compatible)

📐 Dimensions

Length:

Approx. 4415 mm (173.8 in)

Width:

Approx. 1770 mm (69.7 in) (non-widebody), Approx. 1810 mm (71.3 in) (widebody STI)

Height:

Approx. 1440 mm (56.7 in)

Wheelbase:

Approx. 2625 mm (103.3 in)

Ground Clearance:

Approx. 130-140 mm (5.1-5.5 in) (STI), higher for non-turbo

Curb Weight Sti:

Approx. 1470 kg (3240 lbs)

Curb Weight Wrx:

Approx. 1420 kg (3130 lbs)

Wheel Bolt Pattern:

5x100 mm

Wheel Size Sti:

17x8.0 inch (standard), 18x8.0 inch (optional/later models)

Tire Size Sti:

225/45R17 (standard), 225/40R18 (optional)

Wheel Size Wrx:

17x7.0 inch

Tire Size Wrx:

215/45R17

🛡️ Safety Features

NHTSA Front Impact:

4 Stars (Driver), 5 Stars (Passenger) - typical for the era

IIHS Front Offset:

Acceptable (Good performance for the time)

AWD System:

Symmetrical All-Wheel Drive (standard on all variants)

ABS:

Standard Anti-lock Braking System

Traction Control:

Available (VDC - Vehicle Dynamics Control on some models/trims)

Airbags:

Front dual-stage airbags, Side curtain airbags (optional/standard depending on trim)

Seatbelts:

3-point height-adjustable front seatbelts with pre-tensioners and load limiters, 3-point rear seatbelts

Rollover Protection:

Reinforced chassis and A-pillars, designed to withstand rollovers.

💡 Technology Features

Audio System:

Factory AM/FM/CD player, often with optional premium sound system. Basic digital display for clock and radio.

Climate Control:

Manual or automatic climate control (depending on trim level).

Cruise Control:

Standard electronic cruise control.

Vcd:

Vehicle Dynamics Control (Traction and Stability Control) available on select models.

Aux Input:

Typically not standard, but aftermarket solutions are common.

Power Outlets:

12V accessory power outlets.

🔧 Maintenance

Oil Change:

Every 3,000-5,000 miles or 3-6 months (severe duty recommended for performance driving)

Oil Filter Replacement:

With every oil change

Air Filter Replacement:

Every 15,000-30,000 miles or as needed

Spark Plug Replacement Sti:

Platinum: 60,000 miles. Iridium: 100,000 miles. (Check manual for specific plug type)

Coolant Flush:

Every 30,000-60,000 miles or 2-4 years

Timing Belt Replacement:

This generation uses a timing chain, not a belt. However, accessory belts should be inspected regularly and replaced as needed (typically 60,000-100,000 miles).

Brake Fluid Flush:

Every 24,000 miles or 2 years

Differential Fluid Change:

Every 30,000 miles (front and rear, especially for STI)

Engine Oil Sti:

0W-30 or 5W-30 Synthetic (API SN/SP or ILSAC GF-5/GF-6) - consult manual for exact spec and viscosity based on temperature.

Engine Oil Wrx:

5W-30 or 10W-30 Synthetic (API SN/SP or ILSAC GF-5/GF-6)

Coolant:

Subaru Super Coolant (Blue) or equivalent HOAT coolant, mixed 50/50 with distilled water.

Brake Fluid:

DOT 3 or DOT 4 (check manual for specific recommendation, DOT 4 preferred for performance).

Engine Ringland Failure:

More common on EJ257 engines with aggressive tuning or lack of proper maintenance; particularly susceptible to detonation.

Head Gasket Leaks:

While not as prevalent as on earlier Subaru engines, some EJ series can develop head gasket leaks. Early detection is key.

Clutch Wear:

High-performance nature and frequent spirited driving can accelerate clutch wear.

Turbocharger Failure:

Bearing failures or seal leaks can occur with high mileage or improper maintenance (e.g., lack of cool-down periods).

Rust And Corrosion:

Common in areas with road salt; underbody, wheel wells, and door sills are susceptible.

📚 Vehicle History

Subaru Legacy:

Subaru's commitment to All-Wheel Drive and boxer engines established with earlier models like the Leone and Legacy.

Rally Roots:

Direct lineage from Subaru's World Rally Championship (WRC) success, with the Impreza WRX STI being homologated for competition.

Gc8 Generation:

The 2005 model is part of the GC8 generation (or the transition to GD/GG generation depending on market and specific chassis codes), known for its aggressive styling and performance focus.

Gd Generation Transition:

The 2005 model year represents the latter part of the GD generation, which saw significant updates and the introduction of the wider body style for the STI, enhancing stability and handling.

Engine Development:

The EJ series engines, particularly the EJ20 and EJ25 variants, were continuously developed for performance and reliability. The EJ207 and EJ257 were key for the STI's power.

Manufacturing Location:

Japan (Ota City, Gunma Prefecture)

Production Years Gd Generation:

2000-2007

🏆 Awards & Recognition

Car And Driver 10Best:

The Impreza WRX and STI models frequently appeared on Car and Driver's 10Best lists during this era for their performance and value.

Motor Trend Car Of The Year:

While not winning the overall award, the Impreza line was consistently recognized for its performance capabilities.

Rally Championships:

Subaru Impreza models, including the STI, secured numerous manufacturer and driver championships in WRC and other global rallying series.

Consumer Reports:

Consumer Reports ratings for this generation often highlighted performance but noted potential concerns with reliability compared to some Japanese competitors.