The actual failure results for a typical 2008 z4 are available on the Web at https://good-garage-guide.honestjohn.co ... mw/z4/2008
Apparently at 10 years old they have a 74% pass rate which is better than average.
Failure reasons for 2008 Z4 are most likely for Springs, bushes, lamps and tyres, suspension being a particularly weak area compared to all other makes/models. Interestingly steering is 84% better pass rate compared to all other makes models. I've pasted in the figures,
9.8% fail on Suspension, specifically
4.4% fail on Coil springs
3.3% fail on Suspension arms (58% worse than other 2008 cars)
3.1% fail on Pins/bushes/ball joints (52% worse than other 2008 cars)
0.23% fail on Attachment (2 times worse than other 2008 cars)
1.0% fail on Shock absorbers
0.72% fail on Anti-roll bars (70% better than other 2008 cars)
0.72% fail on Front suspension joints
0.32% fail on Wheel bearings
0.045% fail on Trailing arms
0.045% fail on Radius arms
0.045% fail on Tie bars/rods
0.045% fail on Torque/reaction arms
0.045% fail on Macpherson strut
9.2% fail on Lamps, Reflectors and Electrical Equipment (46% better than other 2008 cars), specifically
2.5% fail on Headlamp aim (47% better than other 2008 cars)
2.5% fail on Registration plate lamp (44% better than other 2008 cars)
2.2% fail on Headlamps
1.9% fail on Headlamp (33% better than other 2008 cars)
0.23% fail on Headlamp defects which don't require an aim check on retest (2 times worse than other 2008 cars)
0.23% fail on Headlamp cleaning device (3 times worse than other 2008 cars)
0.045% fail on Headlamp defects which do require an aim check on retest
1.9% fail on Position lamps (56% better than other 2008 cars)
0.54% fail on Horn
0.41% fail on Stop lamp (89% better than other 2008 cars)
0.27% fail on Direction indicators (83% better than other 2008 cars)
0.14% fail on Rear fog lamp
0.090% fail on Hazard warning
0.045% fail on Battery
8.0% fail on Tyres specifically
4.4% fail on Condition
3.8% fail on Tread depth
0.63% fail on Tyre pressure monitoring system (8 times worse than other 2008 cars)
0.090% fail on Size/type
0.045% fail on Valve stem
4.8% fail on Brakes (31% better than other 2008 cars) specifically
2.1% fail on ABS (6 times worse than other 2008 cars)
1.4% fail on Hub components (52% better than other 2008 cars)
0.99% fail on Brake performance (67% better than other 2008 cars)
0.90% fail on Electronic stability system (5 times worse than other 2008 cars)
0.45% fail on Hydraulic systems (56% better than other 2008 cars)
0.23% fail on Parking brake
3.6% fail on Driver's view of the road (36% better than other 2008 cars)
1.5% fail on Exhaust, Fuel and Emissions (36% better than other 2008 cars)
0.72% fail on Road Wheels (110% worse than other 2008 cars)
0.63% fail on Registration plates and VIN
0.54% fail on Seat Belts and Supplementary Restraint Systems
0.23% fail on Steering (84% better than other 2008 cars)
0.090% fail on Body, Structure and General Items (84% better than other 2008 cars)
