🏷️ Basic Information

Make:

Mercedes-Benz

Model:

R-Class

Year:

2009

Chassis Code:

W251

Product Name:

2009 Mercedes R-Class (W251) Service and Repair Manual

👋 Introduction

Positioning:

Luxury crossover SUV positioned as a versatile family vehicle with Mercedes-Benz engineering and comfort.

Competitors:

BMW 5 Series Gran Turismo (later model), Audi Q7, Volvo XC90, Cadillac SRX.

Vehicle Features:

Spacious interior, optional third-row seating, available 4MATIC all-wheel drive, sophisticated ride quality, advanced safety features, and premium Mercedes-Benz interior appointments.

Value:

Empowers owners and independent technicians with factory-level repair information, enabling accurate diagnosis, maintenance, and repair, potentially saving significant costs compared to dealership service.

Purpose:

To provide comprehensive, accurate, and easy-to-understand repair and maintenance information for the 2009 Mercedes R-Class (W251) to enable DIY enthusiasts and professional mechanics to effectively service the vehicle.

📋 Manual Details

Coverage:

All models and all repairs A-Z

Page Count Estimate:

Extensive (detailed step-by-step instructions, diagrams, illustrations, wiring schematics)

Type:

Factory Service and Repair Manual

Language:

English

Format:

PDF

Digital Features:

Searchable text within the PDF for quick information retrieval. Ability to bookmark important sections and print specific pages or diagrams.

📖 Manual Coverage

Systems:

Engine, Control System, Mechanical, Fuel Service, Emission Control, Intake/Exhaust/Cooling, Lubrication, Ignition/Starting/Charging, Automatic Transmission, Manual Transmission, Transfer/Propeller Shaft, Drive Shaft, Differential, Axle/Suspension, Tire & Wheel, Brake Control, Brakes, Parking Brake, Steering Column, Power Steering, Air Conditioning, Supplemental Restraint System (SRS), Seat Belts, Engine Immobilizer, Cruise Control, Wiper & Washer, Door Locks, Meter/Audio/Visual, Horn, Windshield/Glass/Mirrors, Instrument Panel, Seats, Engine Hood/Doors, Exterior & Interior, Electrical Systems, Multiplex/CAN Communication.

Engine Mechanical:

Engine overhaul, piston and ring replacement, cylinder head service, valve train maintenance, crankshaft and bearing service, timing chain/belt replacement.

Engine Control:

Engine Control Module (ECM) diagnostics, sensor testing (MAF, O2, TPS, CKP, CMP), fuel injector testing, ignition system diagnostics (coils, plugs), emissions control systems (catalytic converter, EGR, secondary air injection).

Procedures:

Maintenance, Servicing, Diagnosis, Repair, Troubleshooting, Component Replacement, System Adjustments, Wiring Diagram Interpretation.

Brake Procedures:

Brake pad and rotor replacement, caliper service, brake line and hose inspection/replacement, ABS component testing, parking brake adjustment and repair.

Suspension Steering Procedures:

Strut and shock absorber replacement, spring replacement, control arm and bushing service, ball joint inspection/replacement, power steering pump and rack repair, wheel alignment.

Depth:

Vehicle-specific, factory-level detail identical to dealership technician manuals, covering everything from basic maintenance to complex system diagnostics and complete repairs.

Electrical Diagnostics:

Detailed troubleshooting flowcharts for electrical system faults, power distribution, grounding points, fuse and relay identification, and module testing.

Body And Interior Repair:

Panel removal and installation, door and latch mechanisms, window regulators, seat adjustments and heating elements, airbag system service and replacement, interior trim components.

📊 Manual Specifications

File Type:

PDF

Printability:

All pages are printable; allows for enlarged image printing.

Binding:

Digital (PDF) - no physical binding. Eliminates issues of greasy or torn paper manuals.

Paper Type:

N/A (Digital format)

Operating Systems:

Windows Vista (32/64-bit), XP, ME, 98, NT, 2000, and Mac compatible.

Software Requirements:

Adobe PDF Reader and Winzip (free online).

⚙️ Engine Specifications

Engine Options:

Likely includes 3.0L V6 (e.g., M272 engine code) and 3.5L V6 (e.g., M272 engine code) gasoline engines, and potentially a 3.0L V6 turbodiesel (e.g., OM642 engine code).

Performance Details:

Varies by engine. V6 gasoline engines typically offer a balance of power and refinement. Diesel variants provide strong torque and fuel efficiency. Specific horsepower and torque figures will be detailed within the manual.

Fuel Delivery:

Likely features sophisticated fuel injection systems (e.g., Electronic Fuel Injection - EFI, or Direct Injection for later variants not specified but generally found in Mercedes engines of this era). Details on fuel pump, injectors, and pressure regulators are covered.

Cooling Components:

Engine coolant, radiator, water pump, thermostat, cooling fans, coolant hoses, and expansion tank. The manual will detail inspection, testing, and replacement procedures.

Oil Specifications:

Likely requires synthetic engine oil meeting specific Mercedes-Benz specifications (e.g., MB 229.5 or similar). The manual will provide exact viscosity grades and capacities. Covers oil pump, oil filter, oil pan, and oil pressure.

Common Engine Codes:

M272 (3.0L/3.5L V6 gasoline), OM642 (3.0L V6 turbodiesel). The manual will specify exact codes for all covered variants.

🔧 Transmission

Transmission Type:

Likely the 7-speed automatic transmission (7G-TRONIC) as standard on most models.

Optional Transmission:

While the 7G-TRONIC was prevalent, the manual might cover variations or earlier iterations if applicable to specific configurations.

Transmission Features:

Electronic control, adaptive shifting programs, manual shift mode (Tiptronic). The manual will detail transmission fluid type, capacity, filter replacement, and diagnostic procedures.

Transmission Codes:

722.9 (7G-TRONIC automatic transmission).

📐 Dimensions

Exterior Dimensions:

W251 R-Class is a large crossover/minivan. Specific length, width, height, and wheelbase will be detailed. Typically around 199 inches in length, 78 inches wide, and 67 inches tall, with a wheelbase around 121 inches.

Interior Space:

Known for its spacious cabin, offering ample legroom and headroom, especially in the first two rows. Optional third-row seating is available. The manual covers seat adjustments, trim removal, and interior component access.

Cargo Capacity:

Generous cargo volume, especially with rear seats folded. Specific cubic feet figures for various configurations (seats up/down) will be in the manual.

Curb Weight:

Curb weight varies by engine and drivetrain, typically ranging from approximately 4,600 to 4,900 lbs. Gross Vehicle Weight Rating (GVWR) will also be specified.

🛡️ Safety Features

Safety Ratings:

Mercedes-Benz vehicles of this era generally achieved good safety ratings. NHTSA and IIHS crash test results for the 2009 R-Class will be a key reference point, detailed in the manual's safety sections.

Active Safety:

ABS (Anti-lock Braking System), ESP (Electronic Stability Program), ASR (Traction Control System), Brake Assist (BAS), optional adaptive cruise control (DISTRONIC), tire pressure monitoring system (TPMS).

Adaptive Dampers:

If equipped with optional AIRMATIC suspension, the manual will cover the diagnostics and repair of the adaptive damping system and air springs.

Passive Safety:

Multiple airbags (front, side, curtain, optional rear side), front active head restraints, crumple zones, reinforced body structure. Supplemental Restraint System (SRS) coverage is extensive.

💡 Technology Features

Infotainment System:

Likely features the COMAND infotainment system with a central display, radio, CD/DVD player, navigation (optional), and Bluetooth connectivity. The manual will cover system diagnostics, component replacement (head unit, speakers), and antenna systems.

Driver Aid Systems:

Parking sensors (front and rear), rearview camera (optional), cruise control, and potentially lane departure warning or blind-spot monitoring depending on the trim level. The manual details the operation and repair of these systems.

Connectivity Features:

Bluetooth for hands-free calling and audio streaming, aux input for audio devices. The manual covers the diagnosis and repair of the Bluetooth module and related wiring.

Electrical Architecture:

Features a complex electrical system with multiplexed communication (CAN bus). The manual provides detailed wiring schematics for all circuits, module locations, and diagnostic procedures for electrical faults.

🔧 Maintenance

Scheduled Maintenance:

The manual will provide detailed factory-recommended service intervals for oil changes, fluid flushes (coolant, brake, transmission), filter replacements, spark plugs, and inspections. This will be based on time or mileage (e.g., 'Service A' and 'Service B' or similar designations).

Fluid Types Capacities:

Exact specifications for engine oil (type and viscosity), coolant (type and mixture ratio), brake fluid (DOT 4), power steering fluid, and transmission fluid. Capacities for all fluid reservoirs will be provided.

Coolant Specifications:

Likely requires a specific Mercedes-Benz approved coolant concentrate (e.g., G48 or similar blue/green coolant) mixed with distilled water in a 50/50 ratio. Manual will confirm.

Common Problems:

While the manual focuses on repair, it implicitly addresses common issues by providing solutions. For the W251, potential areas of concern might include air suspension components (if equipped), certain electronic modules, and HVAC system performance. The manual's diagnostic section will be invaluable for troubleshooting these.

Tire Wheel Specifications:

Recommended tire sizes, inflation pressures, wheel specifications (bolt pattern, offset, diameter), and alignment procedures. The manual will cover wheel bearing replacement and suspension component checks.

📚 Vehicle History

Brand History:

Mercedes-Benz has a long-standing reputation for engineering excellence, luxury, and safety, dating back to the invention of the automobile.

R Class Evolution:

The R-Class (W251) was introduced in 2005 as a 'Grand Sports Tourer,' blending elements of an SUV, minivan, and wagon. The 2009 model year would have received minor updates or refinements as part of its lifecycle.

Production Details:

The R-Class was produced at the Mercedes-Benz plant in Tuscaloosa, Alabama, USA. Sales figures and market reception were mixed, leading to its discontinuation in many markets after 2013.

🏆 Awards & Recognition

Industry Awards:

While specific awards for the 2009 model are not widely publicized, Mercedes-Benz vehicles consistently receive recognition for safety, luxury, and engineering from various automotive publications and organizations.