Segment:
Executive Sedan / Luxury Mid-size
Competitors:
Mercedes-Benz W124 E-Class, Audi 100/200, Jaguar XJ6, Volvo 740/760.
Key Strengths:
Renowned BMW driving dynamics, build quality, inline-six engine smoothness, sophisticated engineering for its era.
Design Philosophy:
The E28 generation represented a refinement of BMW's traditional 'Ultimate Driving Machine' ethos with improved aerodynamics and modern amenities.
Manual Value Proposition:
Essential for owners and technicians looking to maintain, repair, and restore the E28 525i, preserving its performance and longevity.
Applicable Years:
1981, 1982, 1983, 1984, 1985, 1986, 1987, 1988
Estimated Pages:
Comprehensive (typically 500+ pages for this era)
Type:
Workshop Service Repair Manual
Engine Mechanical:
Full overhaul, cylinder head, block, crankshaft, pistons, connecting rods, timing belt/chain, lubrication system, cooling system.
Engine Management:
Fuel injection (Bosch L-Jetronic/Motronic), ignition system, sensors (MAF, O2, coolant temp), troubleshooting, component testing.
Transmission:
Manual and Automatic transmission overhaul, clutch, driveshafts, differential.
Suspension:
Front and rear suspension, shock absorbers, springs, bushings, control arms, steering linkage.
Brakes:
Front and rear brake systems (discs), hydraulic lines, master cylinder, calipers, ABS (if equipped), bleeding procedures.
Electrical:
Wiring diagrams, starter, alternator, battery, lighting, fuses, relays, power windows, door locks, instrument cluster.
Body And Chassis:
Body panel removal/installation, interior trim, bumpers, glass, seals, frame alignment (basic).
Maintenance:
Scheduled maintenance, oil changes, filter replacements, spark plugs, coolant flushes, brake fluid changes.
Diagnostics:
Troubleshooting guides, symptom-based diagnostics, fault code interpretation (OBD I era).
Repair:
Step-by-step repair instructions for all major systems.
Rebuilds:
Engine and transmission overhaul procedures with detailed component specifications.
Adjustments:
Valve adjustments, idle speed adjustments, timing adjustments.
Depth:
Comprehensive, from basic maintenance to full mechanical rebuilds and advanced diagnostics.
Engine Type:
Naturally Aspirated Inline-6
Displacement:
2.5 Liters (2494 cc)
Bore X Stroke:
84.0 mm x 75.0 mm
Compression Ratio:
8.5:1 (typical)
Horsepower:
168 hp @ 5800 rpm (approx.)
Torque:
164 lb-ft @ 4000 rpm (approx.)
Fuel Delivery:
Bosch L-Jetronic or Motronic electronic fuel injection
Fuel Type:
Premium Unleaded Gasoline (91+ octane recommended)
Coolant Type:
BMW recommends BMW Coolant/Antifreeze or equivalent ethylene glycol-based with corrosion inhibitors. (Refer to manual for specific BMW part number)
Oil Capacity:
Approximately 5.5 Liters (5.8 US Quarts) with filter change.
Recommended Oil Viscosity:
SAE 20W-50 or 15W-40 depending on climate (Refer to manual for specific API service classification and BMW LL-XX approval codes).
Timing Drive:
Timing Chain
Type:
Getrag 260 5-speed Manual Transmission
Type:
ZF 4HP22 4-speed Automatic Transmission
Manual Transmission Fluid
Fluid Type:
GL-4 or GL-5 Manual Transmission Fluid (refer to manual for specific viscosity and BMW approval).
Automatic Transmission Fluid
Fluid Type:
Dexron III / Mercon or equivalent (refer to manual for specific BMW approval and capacity).
Clutch:
Hydraulically actuated single dry plate clutch.
NHTSA Front Impact:
Not rated by modern standards (1980s era vehicle).
IIHS Crash Tests:
Not rated by modern standards (1980s era vehicle).
ABS:
Optional Anti-lock Braking System (ABS)
Airbags:
Driver airbag became standard in later years of the E28 production. Passenger airbag not generally available on this model.
Seatbelts:
3-point inertia-reel seatbelts with pretensioners (driver/front passenger).
Chassis Design:
Unitized steel body with crumple zones.
Audio System:
Factory fitted cassette player with AM/FM radio, optional CD changer.
Climate Control:
Manual or optional automatic climate control system.
Cruise Control:
Standard cruise control system.
Diagnostics Port:
Early OBD I system, accessed via diagnostic connector under the hood or dash (refer to manual for location and procedure).
Oil Change:
Every 7,500 - 10,000 miles or 12 months, whichever comes first (depending on driving conditions).
Spark Plugs:
Inspect every 15,000 miles, replace as needed (recommend high-quality platinum or iridium plugs, e.g., Bosch W8AC or equivalent).
Coolant Flush:
Every 2 years or 30,000 miles.
Brake Fluid:
Flush and replace every 2 years.
Power Steering Fluid:
BMW Power Steering Fluid or ATF Dexron III / Mercon (Refer to manual for specific BMW approval).
Brake Fluid Type:
DOT 4 Premium Brake Fluid (Refer to manual for specific BMW approval).
Engine Oil Leaks:
Common leaks from valve cover gasket, oil pan gasket, and oil filter housing due to aged seals.
Cooling System:
Radiator, hoses, and water pump degradation; potential for head gasket failure if overheated.
Fuel System:
Clogged fuel injectors, failing fuel pumps, and aged fuel lines are potential issues.
Electrical Gremlins:
Corroded grounds, failing relays, and brittle wiring insulation can cause intermittent electrical problems.
Suspension Wear:
Worn control arm bushings, ball joints, and sway bar links are common and affect handling.
Bmw Legacy:
BMW has a long-standing reputation for engineering performance sedans with a focus on driver engagement and advanced technology.
E28 Introduction:
The E28 generation succeeded the E12 5 Series and was produced from 1981 to 1988. It was a significant step forward in terms of design, aerodynamics, and technology.
E28 Positioning:
The 525i was positioned as a strong mid-range model in the E28 lineup, offering a balance of performance and luxury.
Production Period:
1981-1988
Manufacturing Locations:
Germany (Dingolfing plant)
Editorial Awards:
Consistently praised by automotive journalists of its era for performance, handling, and build quality. Often cited as a benchmark for sports sedans.
Driving Dynamics:
Highly rated for its responsive steering, balanced chassis, and powerful inline-six engine, earning it a reputation as a driver's car.
Manual Accuracy:
Reputable workshop manuals of this era are generally considered highly accurate and based on manufacturer specifications.
