Segment:
Premium two-seater sports roadster
Competitors:
Audi TT Roadster, Porsche Boxster, Mercedes-Benz SLK-Class
Design:
Long hood, short deck, classic roadster proportions, retractable hardtop
Driving Dynamics:
Rear-wheel drive, balanced chassis, responsive handling
Target Audience:
Enthusiast drivers seeking a blend of performance, luxury, and open-top driving experience
Engine:
Comprehensive engine overhaul, diagnosis, and repair for all Z4 variants
Transmission:
Repair, service, and diagnosis for automatic and manual transmissions
Brakes:
Detailed procedures for ABS, DSC, brake pad replacement, rotor service, and hydraulic system maintenance
Electrical:
Wiring diagrams, component testing, diagnostic procedures for all electrical systems
Suspension:
Front and rear suspension component replacement, alignment specifications, shock absorber service
Steering:
Power steering system diagnosis and repair, steering column service
Bodywork:
Body panel alignment, convertible top mechanism service, interior trim removal and installation
HVAC:
Air conditioning system service, heater core replacement, climate control diagnostics
Maintenance:
Scheduled maintenance, oil changes, filter replacements, fluid checks
Troubleshooting:
Diagnostic trees and symptom-based troubleshooting for common issues
Repair:
Step-by-step repair instructions for all major vehicle components
Replacement:
Detailed instructions for replacing common wear items and major components
Diagnostics:
OBD-II code interpretation, component testing procedures, scan tool usage
Rebuilding:
Complete engine and transmission rebuild procedures with torque specifications and clearances
Depth:
Comprehensive: Covers routine maintenance to complete engine and transmission overhauls, including advanced diagnostics and electrical troubleshooting.
Engine Codes:
N55B30 (30i), N20B20 (28i)
Sdrive28I Horsepower:
240 hp @ 5,000-6,500 rpm
Sdrive28I Torque:
255 lb-ft @ 1,250-4,800 rpm
Sdrive35Is Horsepower:
300 hp @ 5,800-6,000 rpm
Sdrive35Is Torque:
300 lb-ft @ 1,350-4,500 rpm
Injection Type:
Direct Injection (High-Pressure)
Fuel Type:
Premium Unleaded Gasoline (91 octane or higher recommended)
Configuration:
Inline 4-cylinder (28i), Inline 6-cylinder (35is)
Valvetrain:
Double Overhead Camshafts (DOHC), 4 valves per cylinder, Double VANOS, Valvetronic
Cooling System:
Pressurized liquid-cooled system with electric fan
Sdrive28I:
8-speed Steptronic automatic transmission
Sdrive35Is:
7-speed M Double Clutch Transmission (M DCT) with Drivelogic
Availability:
Manual transmission was not offered for the 2015 model year Z4 in most markets.
Automatic Modes:
Sport, Manual modes with paddle shifters
M Dct Features:
Launch Control, Low-Speed Drivability
Automatic Transmission Fluid Atf:
BMW recommends specific Steptronic ATF (e.g., ATF 3+
M Dct Fluid:
BMW M DCT Fluid
NHTSA Overall:
Not officially rated by NHTSA for 2015 model year due to low volume sports car classification.
Dsc:
Dynamic Stability Control with DTC (Dynamic Traction Control)
ABS:
Anti-lock Braking System
Drivetrain Stability:
Electronic Limited Slip Differential (eLSD) on sDrive35is
Airbags:
Front airbags, side airbags integrated into seats, rollover protection system (pop-up bars)
Seatbelts:
Three-point inertia-reel seat belts with pretensioners and force limiters
System:
BMW iDrive infotainment system (Professional Navigation system optional)
Display:
6.5-inch or 8.8-inch color display
Optional Features:
Parking Assistant, Backup camera, Adaptive headlights
Connectivity Options:
Bluetooth, USB audio interface, optional SiriusXM Satellite Radio tuner
Oil Change Interval:
Condition Based Service (CBS) system typically recommends oil changes between 10,000-15,000 miles or annually, whichever comes first.
Brake Fluid Flush:
Every 2 years, regardless of mileage.
Engine Air Filter:
Typically every 30,000-40,000 miles or as indicated by CBS.
Cabin Air Filter:
Typically every 15,000-20,000 miles or annually.
Engine Oil:
BMW Longlife-01 (LL-01) or Longlife-04 (LL-04) compliant synthetic oil, typically 5W-30 or 0W-40.
Coolant:
BMW Blue Long-Life Coolant (G48), mixed 50/50 with distilled water.
Brake Fluid:
DOT 4 LV (Low Viscosity) or DOT 4+.
Common Complaints:
Occasional issues with electric power steering pump, oil leaks from valve cover gasket or oil pan, sticky convertible roof mechanisms, and potential turbocharger issues on higher mileage N55 engines.
Legacy:
BMW's long history of producing iconic roadsters, following in the footsteps of the 328, 507, and Z3/Z4 generations.
Generation:
E89 (second generation Z4), introduced in 2009, updated with a facelift for 2013. The 2015 model represents the later phase of this generation.
Manufacturing Location:
Regensburg, Germany