Segment:
Sport Sedan/Coupe/Convertible, Premium Mid-Size
Target Audience:
Enthusiast drivers seeking performance, luxury, and advanced technology.
Key Rivals:
Audi A4, Mercedes-Benz C-Class, Lexus IS, Infiniti G35/G37
Engine Technology:
Twin-turbocharged inline-six engine (N54/N55), Direct Injection, Valvetronic, VANOS
Driving Dynamics:
Rear-biased weight distribution, sophisticated suspension tuning, optional xDrive AWD.
Interior Quality:
Premium materials, driver-focused cockpit, advanced iDrive infotainment system.
Engine Mechanical:
Complete overhaul, component testing, timing, seals, gaskets, lubrication system
Engine Management:
Fuel injection, ignition system, emissions control, sensors, actuators, DME (Digital Motor Electronics)
Transmission:
Manual (Getrag GS6-37BZ, GS6-17BG) and Automatic (ZF 6HP19, 6HP26, 6HP28) RWD/xDrive variants, fluid service, rebuild procedures
Drivetrain:
Driveshafts, differentials (rear and front for xDrive), CV joints, transfer case (xDrive)
Suspension:
Front and rear suspension components, struts, shocks, control arms, sway bars, bushings, alignment specifications
Brakes:
Hydraulic system, ABS, DSC (Dynamic Stability Control), EBD, brake pad/rotor replacement, caliper service, bleeding procedures, parking brake
Steering:
Power steering system (hydraulic), steering rack, tie rods, steering column, alignment
Electrical System:
Battery, charging system, starter, lighting (headlights, taillights, interior), fuses, relays, wiring diagrams
Body And Chassis:
Body panels, doors, hood, trunk, interior trim, chassis components, welding, structural repair (limited in typical PDF manuals)
Climate Control:
HVAC system, refrigerant handling, blower motor, evaporator, heater core, climate control unit
Comfort And Convenience:
Power windows, power locks, mirrors, seats, sunroof, keyless entry, central locking
Safety Systems:
Airbags (SRS), seat belts, pre-tensioners, related sensors and control modules
Infotainment And Navigation:
Radio, CD player, iDrive system (CCC or CIC depending on year), display, speakers, antenna (basic troubleshooting and component identification)
Routine Maintenance:
Oil changes, filter replacements, fluid checks and top-offs, spark plug replacement, brake inspections
Troubleshooting:
Diagnostic trouble codes (DTCs), symptom-based troubleshooting, electrical diagnostics, common failure analysis
Repair And Rebuild:
Component removal and installation, internal engine/transmission repair (where applicable), brake caliper overhaul, suspension component replacement
Diagnostics:
Use of diagnostic tools (e.g., ISTA/D, DIS), reading live data, actuator tests, component coding
Replacements:
Replacement of all major and minor components, sensors, actuators, modules, and accessories
Adjustments:
Wheel alignment, belt tensioning, idle speed adjustments (where applicable)
Depth Of Coverage:
Comprehensive from basic fluid services to in-depth engine and transmission overhauls, including electrical system diagnostics.
Diagnostic Tools:
Mentions procedures requiring BMW proprietary diagnostic equipment (ISTA/D, ISTA/P) for certain electronic modules and coding.
Wiring Diagrams:
Detailed electrical wiring diagrams for all systems, crucial for electrical troubleshooting.
Transmission Type 335I:
6-speed Manual (Getrag GS6-37BZ)
Transmission Type 335Xi:
6-speed Manual (Getrag GS6-17BG with xDrive interface)
Transmission Type 335I:
6-speed Automatic (ZF 6HP19, later 6HP26 with Steptronic)
Transmission Type 335Xi:
6-speed Automatic (ZF 6HP26 with xDrive interface)
Automatic Transmission Features:
Steptronic manual shifting mode, adaptive shift logic.
Manual Transmission Features:
Close-ratio gearing, dual-mass flywheel.
Manual Transmission Fluid:
BMW MTF LT-2 (or equivalent API GL-4/GL-5 specification)
Automatic Transmission Fluid:
ZF Lifeguardfluid 6 (or equivalent ATF specifications like Mercon SP, Dexron VI)
Oil Change Interval:
Variable Oil Service Interval (Condition Based Service - CBS), typically every 10,000-15,000 miles or 12-24 months, whichever comes first.
Engine Air Filter:
Every 30,000 - 60,000 miles or as indicated by CBS.
Cabin Air Filter:
Every 15,000 - 30,000 miles or as indicated by CBS.
Spark Plugs:
Typically every 60,000 miles for N54/N55 engines.
Brake Fluid:
Every 2 years, regardless of mileage.
Coolant:
Initial fill is long-life; replacement typically every 4-5 years or 100,000 miles.
Engine Oil Specification:
BMW Longlife-01 (LL-01) or Longlife-04 (LL-04) approved synthetic oil, typically 5W-30 or 5W-40.
Coolant Specification:
BMW Blue Antifreeze/Coolant (G48 or equivalent)
Power Steering Fluid:
Pentosin CHF 11S or equivalent (specific to hydraulic systems).
Turbocharger Failures:
Early N54 models (pre-2009) prone to turbo wastegate rattle and premature failure due to design. High-pressure fuel pump (HPFP) failures are also common in early N54s, leading to misfires and stalling.
Ignition Coils And Spark Plugs:
Can fail prematurely, causing rough running and misfires.
Oil Gaskets And Seals:
Valve cover gasket, oil pan gasket, and oil filter housing gasket are known to leak over time.
Water Pump And Thermostat:
Electric water pump failures can cause overheating. Thermostat failures can lead to temperature regulation issues.
Vacuum Lines And Boost Leaks:
Cracked or disconnected vacuum lines can affect boost pressure and engine performance.
Power Steering Pump:
Can develop leaks or fail, leading to loss of power steering assist.