🏷️ Basic Information

Make:

Cadillac

Model:

STS

Year:

2006

Chassis Code:

GM Sigma (first generation)

👋 Introduction

Segment:

Luxury Sport Sedan

Target Audience:

Discerning luxury car buyers seeking performance, comfort, and advanced technology.

Competitors:

BMW 5 Series, Mercedes-Benz E-Class, Audi A6, Lexus GS, Infiniti M.

Design Philosophy:

American interpretation of luxury sport sedan, blending performance with Cadillac's distinct styling cues.

Platform:

GM Sigma platform, shared with the Cadillac CTS and SRX, known for its rear-wheel-drive bias and handling capabilities.

📋 Manual Details

Coverage Scope:

All models, engines, trim levels, and transmission types for the 2006 Cadillac STS.

Estimated Page Count:

Extensive (typically over 2000 pages for a complete workshop manual).

Type:

Complete Workshop Service Repair Manual

Language:

English

Format:

Downloadable (PDF)

📖 Manual Coverage

Engine Mechanical:

Engine assembly, disassembly, cylinder head, valve train, crankshaft, pistons, connecting rods, lubrication system, cooling system, intake and exhaust manifolds.

Engine Performance:

Fuel system (injection, pumps, injectors), ignition system (coils, plugs), emissions control, engine control module (ECM) diagnostics.

Transmission:

Automatic transmission service (disassembly, assembly, fluid changes, torque converter), transmission control module (TCM) diagnostics.

Drivetrain:

Driveshaft, CV joints, differential, all-wheel-drive (AWD) system components.

Suspension:

Front and rear suspension systems, shock absorbers, struts, control arms, sway bars, bushings, alignment procedures.

Steering:

Power steering system, steering rack, steering column, wheel alignment.

Brakes:

Brake system components (discs, pads, calipers, lines), ABS, traction control, parking brake, brake bleeding procedures.

Electrical System:

Battery, charging system (alternator), starting system (starter), lighting system, wiring diagrams, fuses, relays.

Body And Frame:

Body panels, doors, hood, trunk, bumpers, chassis structure, corrosion protection.

HVAC:

Heating, ventilation, and air conditioning system components, refrigerant handling, diagnostics.

Interior:

Seats, dashboard, trim panels, airbags, seat belts, interior lighting.

Diagnostics:

On-Board Diagnostics (OBD-II) procedures, diagnostic trouble codes (DTCs), scan tool usage, component testing.

Routine Maintenance:

Oil and filter changes, fluid level checks and top-offs, tire rotation and pressure checks, spark plug replacement, air filter replacement.

Troubleshooting:

Step-by-step diagnostic procedures for common and uncommon faults across all vehicle systems.

Repair And Replacement:

Detailed instructions for removing, repairing, and reinstalling all major and minor components.

Wiring And Schematics:

Comprehensive electrical wiring diagrams for all vehicle systems, including power distribution, grounds, and signal paths.

Specifications And Tolerances:

Torque specifications for fasteners, diagnostic data, component clearances, and operating parameters.

Depth:

Comprehensive, covering everything from basic maintenance to complex diagnostics and complete overhauls. Includes detailed component diagrams and procedural steps.

📊 Manual Specifications

File Type:

PDF (Portable Document Format)

Quality:

High quality, designed for clarity with detailed text and images. Printable page-by-page or in its entirety.

Binding:

N/A (Downloadable digital format)

Paper:

N/A (Digital format, printable on various paper types)

Device Compatibility:

Compatible with all PC and Mac computers, tablets, and mobile phones. Requires Adobe Reader (free download).

⚙️ Engine Specifications

Engine Code 1:

L37 (Northstar V8)

Displacement 1:

4.6L (281 cu in)

Configuration 1:

DOHC 32-valve V8

Horsepower 1:

320 hp @ 6400 rpm

Torque 1:

315 lb-ft @ 4400 rpm

Fuel System 1:

Sequential Port Fuel Injection (SFI)

Compression Ratio 1:

10.5:1

Engine Code 2:

LY7 (3.6L V6)

Displacement 2:

3.6L (220 cu in)

Configuration 2:

DOHC 24-valve V6

Horsepower 2:

255 hp @ 6200 rpm

Torque 2:

252 lb-ft @ 4400 rpm

Fuel System 2:

Sequential Port Fuel Injection (SFI)

Compression Ratio 2:

10.2:1

🔧 Transmission

Type:

6-speed automatic (6L80/6L70 for V8, 6L70 for V6)

Gear Ratios:

Refer to specific transmission section for detailed ratios (e.g., 4.06:1 first gear).

Fluid Type:

Dexron VI Automatic Transmission Fluid (ATF)

Drivetrain Options:

Rear-wheel drive (RWD) or All-wheel drive (AWD) available for both engines.

Shift Modes:

Driver Shift Control (DSC) for manual gear selection.

📐 Dimensions

Length:

192.3 in (4884 mm)

Width:

72.5 in (1841 mm)

Height:

57.6 in (1463 mm)

Wheelbase:

113.5 in (2883 mm)

Curb Weight V6 Rwd:

3927 lbs (1781 kg)

Curb Weight V8 AWD:

4210 lbs (1909 kg)

🛡️ Safety Features

NHTSA Front Impact:

5 Stars (Driver & Passenger)

NHTSA Side Impact:

5 Stars (Front & Rear Passengers)

IIHS Front Offset:

Good

ABS:

Standard 4-wheel antilock disc brakes

Traction Control:

Standard All-Speed Traction Control (TCS)

Stability Control:

Standard StabiliTrak Electronic Stability Control

Airbags:

Dual-stage front airbags, front side-impact airbags, roof-mounted curtain airbags.

Seat Belts:

Front pretensioners with load limiters, rear LATCH system.

💡 Technology Features

Available System:

Infiniti audio system with Bose speakers, CD player, MP3 capability, and optional navigation system.

Connectivity:

Optional Bluetooth hands-free calling, auxiliary audio input.

Adaptive Cruise Control:

Optional; maintains set speed and distance to vehicle ahead.

Parking Assist:

Optional rear parking assist sensors.

Headlights:

Standard HID (High-Intensity Discharge) Xenon headlights with automatic leveling, optional adaptive forward lighting.

🔧 Maintenance

Oil Change Interval:

Every 7,500 miles or 12 months, whichever comes first (using synthetic oil).

Air Filter Replacement:

Every 45,000 miles or as needed.

Spark Plug Replacement V6:

Every 90,000 miles (NGK iridium).

Spark Plug Replacement V8:

Every 100,000 miles (ACDelco iridium or equivalent).

Engine Oil V6:

SAE 0W-30 Synthetic, API SM/SN certified.

Engine Oil V8:

SAE 5W-30 Synthetic, API SM/SN certified.

Coolant:

Dex-Cool (GM P/N 12346517 or equivalent), 50/50 mixture with distilled water.

Brake Fluid:

DOT 3 or DOT 4.

Northstar Head Gaskets:

While improved in later Northstar iterations, the 'thread-insert' type head gasket failures can still occur if overheated. The manual covers inspection and repair procedures.

Suspension Bushings:

Worn control arm bushings and sway bar links can lead to noise and handling degradation. The manual details their replacement.

HVAC Actuators:

Faulty blend door actuators can cause temperature control issues. The manual provides diagnostic steps for these components.

📚 Vehicle History

Brand Legacy:

Cadillac, a division of General Motors, has a long history of producing American luxury vehicles, known for comfort and technological innovation.

Sts Lineage:

The STS (Seville Touring Sedan) replaced the outgoing Cadillac Seville. It represented a significant shift for Cadillac, adopting a rear-wheel-drive platform and focusing on a more dynamic driving experience.

Manufacturing Location:

Lansing Grand River Assembly Plant, Lansing, Michigan, USA.

Production Years:

2005-2011 (First Generation).

🏆 Awards & Recognition

Year Award 1:

Named to Car and Driver's 10Best Trucks and Cars for 2005 (though this was for the previous generation Seville; the STS carried the torch for Cadillac's luxury sedan segment).

Year Award 2:

Received generally positive reviews for its chassis dynamics and ride comfort upon its introduction.