This comprehensive Mercedes 300 SEL 1988-1991 Service Repair Manual provides you with the complete factory service and repair information you need to maintain and repair your vehicle. The manual covers everything from routine maintenance like oil changes and filter replacements to more complex repairs like engine, transmission, and brake system work. The manual includes detailed instructions and diagrams to guide you through every step of the repair process. You'll find information on inspecting component condition, checking fluid levels, adjusting settings, replacing parts, and troubleshooting problems. This manual will help you understand how your vehicle works and give you the confidence to tackle any repair job. The manual covers all models of the Mercedes 300 SEL produced between 1988 and 1991, including the 1988, 1989, 1990, and 1991 model years. This manual is the same one used by your local Mercedes dealer, so you can be sure you're getting the most accurate and up-to-date information available. This manual includes information on: * Inspecting component condition * Inspecting condition of lines and hoses * Inspecting components, lines and hoses * Suspension and body structure inspection * Water leakage and corrosion inspection * Engine oil and filter change * Adjusting valve clearance * Checking valve clearance * Checking and adjusting idle speed * Checking injection timing * Adjusting injection timing * Replacing fuel filter * Cleaning metal reinforced air filter element * Replacing air filter elements * Checking condition and tension of V-belts * Inspecting poly V-belt * Checking intake & exhaust manifold seating * Replacing oxygen sensor * Check spark plugs, replace if necessary * Replacing spark plugs * Checking coolant level & antifreeze protection * Checking cooling & heating system * Replacing coolant * Adjust engine stop, re-torque engine mount bolts * Checking clutch disk for wear * Manual transmission oil change * Manual transmission, checking & correcting oil level * Automatic transmission fluid and filter change * Automatic transmission, checking & correcting fluid level * Transfer case fluid change * Transfer case, checking & correcting fluid level * Clutch system, checking & correcting fluid level * Clutch system, inspect * Inspecting & lubricating throttle linkage * Checking and adjusting idle speed adjuster * Level control,ADS,4MATIC,fluid level * Inspecting self-leveling suspension * Front axle, checking & correcting oil level * Checking front axle ball joints * Checking ball joints using special tool * Rear axle oil change * Rear axle, checking & correcting oil level * Rear axle mount, adjusting limiting stop * Inspecting & rotating wheels * Inspecting tires * Correcting tire pressure * Tightening wheel bolts * Inspecting drive shaft flexible coupling * Checking brake fluid level * Inspecting brake lines * Checking brake pads & disk thickness * Inspecting & cleaning brake disks * Inspecting parking brake cable * Adjusting parking brake * Replacing brake fluid * Brake test, parking brake check * Check power steering fluid level * Checking steering play * Re-tightening steering bolts * Checking fuel system condition * Re-tightening exhaust flange * Re-tightening exhaust system connections * Checking & correcting battery fluid level * Checking warning & indicator lamps * Cleaning water drains * Removing and installing engine compartment lower panel * Lubricating door hinges * Lubricating door locks * Hydraulic top, checking & correcting fluid level * Sunroof, clean & grease rails * Soft top, checking locking tabs * Checking & correcting windshield washer fluid level * Cleaning cassette deck tone head * Cleaning antenna mast * Headlamp & exterior lamp inspection * Windshield & headlamp wiper & washer inspection * Replacing windshield wiper blade * Checking & correcting AC refrigerant charge * Replacing dust filter for heating & ventilation * Replacing active charcoal filter * Replacing recirculating air filter * Lubricating folding side mirror * Lubricating hood * Inspecting safety belts * Backrest lock - check operation * Removing & installing lower noise encapsulation panels * Checking body for paint damage

The Mercedes-Benz 300 SEL, produced from 1988 to 1991, marked the end of an era for the German automaker's iconic S-Class lineup. This stately sedan, built on the W126 platform, represented the epitome of luxury and engineering excellence, embodying the hallmark Mercedes-Benz attributes of comfort, durability, and performance. The 300 SEL was powered by a 3.0-liter inline-six engine, known for its smooth operation and impressive torque. This engine, coupled with a robust four-speed automatic transmission, delivered a refined driving experience, capable of pushing the 300 SEL from 0 to 60 mph in around 9 seconds. However, the true essence of the 300 SEL lay in its opulent interior. Luxurious leather seats, intricate wood trim, and advanced features like automatic climate control and cruise control epitomized the ultimate driving experience. The car's design, with its classic long hood, flowing lines, and timeless elegance, signified its status as a true flagship model. Beyond its exquisite features, the Mercedes-Benz 300 SEL became synonymous with safety and reliability. Featuring a rigid passenger cabin, advanced anti-lock braking system, and a suite of passive safety measures, it set the benchmark for automotive safety during its time. The car's reputation for durability and longevity also cemented its place in automotive history, with many 300 SELs still gracing roads worldwide. Although production of the W126 300 SEL ceased in 1991, its legacy continues. The model's timeless design, sophisticated engineering, and enduring quality remain a testament to the enduring appeal of the Mercedes-Benz brand.