🏷️ Basic Information Identification Make: BMW Model: 525i Chassis Code: E28 Generation Generation Name: First Generation E28 Generation Years: 1981-1988 Codes Engine Code Common: M30B25 👋 Introduction Market Position Market Segment: Executive Sedan, Luxury Sports Sedan Competitor Comparison: Competed with Mercedes-Benz W123/W124, Audi 100, Volvo 240, Jaguar XJ Series Key Features Driving Dynamics: Renowned for its balanced chassis, rear-wheel drive, and driver-focused engineering Build Quality: Exemplary German engineering and build quality, designed for longevity Powertrain Reliability: M30 engine series is known for its robust construction and durability when properly maintained Interior Comfort: Comfortable and driver-oriented cabin with high-quality materials 📋 Manual Details Coverage Areas Coverage Scope: Comprehensive Service, Repair, and Maintenance Page Count Estimated Page Count: 1000+ Manual Type Manual Type: Workshop Service Repair Manual Language Language: English Format Format: Digital Download (PDF) 📖 Manual Coverage Systems Covered Engine Mechanical: Complete overhaul, component diagnostics, timing belt/chain replacement, cooling system, lubrication system Fuel System: Bosch L-Jetronic/Motronic injection system, fuel pump, injectors, fuel lines, tank Ignition System: Distributor, ignition coils, spark plugs, timing adjustments Exhaust System: Catalytic converter, mufflers, exhaust manifold, O2 sensors (if applicable) Transmission Manual: Clutch, gearbox, drive shafts, differential, fluid changes, rebuild procedures Transmission Automatic: Fluid changes, torque converter, electronic controls (if applicable), general maintenance Brakes: Hydraulic system, ABS (if equipped), brake discs, pads, calipers, master cylinder, lines, bleeding procedures Suspension: Front struts, rear shocks, control arms, bushings, anti-roll bars, steering linkage Steering: Power steering system, steering rack/box, tie rods, steering column Electrical System: Battery, alternator, starter, wiring diagrams, fuses, relays, lighting systems Climate Control: HVAC system, blower motor, A/C system, heater core, diagnostics Body And Interior: Body panel removal/installation, door mechanisms, interior trim, seats, glass replacement Diagnostics And Troubleshooting: Step-by-step diagnostic procedures, common fault codes, symptom-based troubleshooting Procedures Included Routine Maintenance: Oil changes, filter replacements, spark plug checks, fluid level checks, tire rotations Major Repairs: Engine rebuilds, transmission overhauls, brake system repairs, suspension component replacement Component Replacement: Alternator, starter, water pump, fuel pump, radiator, clutch assembly Wiring Diagrams: Complete and detailed electrical schematics for all systems Torque Specifications: Precise torque values for all critical fasteners Special Tool Identification: Identification of BMW-specific tools required for certain procedures Technical Depth Depth Of Information: From basic DIY maintenance to advanced engine and transmission rebuilds Diagnostic Capability: Extensive diagnostic trees and component testing procedures Rebuild Instructions: Detailed step-by-step instructions for complete engine and gearbox overhauls 📊 Manual Specifications File Format File Type: PDF Searchability: Text-searchable for quick information retrieval Print Quality: High-resolution for clear diagrams and text Print Quality Diagrams Clarity: Clear, well-annotated technical drawings and schematics Binding Type Binding Type: N/A (Digital Download) Paper Type Paper Type: N/A (Digital Download) ⚙️ Engine Specifications Primary Engine Engine Type: Inline-6 Cylinder, SOHC Engine Displacement: 2.7 Liters (2693 cc) Engine Code: M30B27 (known as 'Eta' or 'Economy' version) Bore X Stroke: 89.0 mm x 73.5 mm Performance Horsepower: Approx. 121 hp @ 4800 rpm (US Spec) Torque: Approx. 170 lb-ft @ 2400 rpm (US Spec) Fuel System Fuel Delivery: Bosch L-Jetronic Fuel Injection Fuel Type: Unleaded Gasoline Engine Internals Compression Ratio: 8.3:1 (for M30B27 Eta) Cooling System Cooling Type: Water-Cooled, Thermostatically Controlled Fan 🔧 Transmission Standard Transmission Type Standard: 4-Speed Manual Optional Transmission Type Optional: 3-Speed Automatic (ZF 3HP22) Features Rear Axle Ratio: Typically 3.25:1 (Manual) / 3.46:1 (Automatic for Eta models) Fluid Specs Manual Transmission Fluid: BMW MTF LT-2 or equivalent (e.g., Pentosin, Red Line MTL) Automatic Transmission Fluid: Dexron III / Mercon compatible fluid 📐 Dimensions Exterior Length: 4755 mm (187.2 in) Width: 1700 mm (66.9 in) Height: 1420 mm (55.9 in) Wheelbase: 2795 mm (110.0 in) Weights Curb Weight: Approx. 1450 kg (3197 lbs) Gross Vehicle Weight Rating: N/A (Varies by spec) 🛡️ Safety Features Ratings Crash Test Ratings: NHTSA ratings from the era, generally considered safe for its time; specific ratings may vary by year/market. Active Features ABS: Optional Anti-lock Braking System (ABS) Passive Features Seatbelts: Three-point inertia-reel seatbelts Head Restraints: Front and rear head restraints Crumple Zones: Designed with front and rear crumple zones for impact absorption 💡 Technology Features Infotainment Audio System: Factory AM/FM/Cassette stereo system (upgradable). Climate Control Features: Manual or optional automatic climate control (ECC - Electronic Climate Control). Driver Assistance Cruise Control: Standard or optional cruise control system. Connectivity Connectivity Features: Limited by era; primarily focused on mechanical and electrical diagnostics rather than modern digital connectivity. 🔧 Maintenance Service Intervals Oil Change Interval: Typically every 5,000-7,500 miles or 6-12 months, depending on driving conditions. Spark Plug Replacement: Approximately every 20,000-30,000 miles, depending on spark plug type. Coolant Flush: Every 2-3 years or 30,000 miles. Fluid Specifications Engine Oil Specification: API SG or higher, SAE 15W-40 or 10W-40 (check owner's manual for specific climate recommendations) Engine Oil Capacity: Approximately 5.7 Liters (6.0 US Quarts) with filter change Coolant Type: Ethylene Glycol based antifreeze, typically BMW Blue...