Front control arm bush knock over broken surfaces
- Typically appears
- 50,000+ miles
- What to inspect
- Drive a rough road and listen for a knock at low speed

A 2020 BMW X4 is now 6 years old, so an average example has covered around 81,000 miles. An early car in the generation · most of the launch teething issues were still being worked through, so recall completion and dealer rectification history matter. Check the state safety inspection and service history alongside the documented faults below, which are sorted by whether a 2020 car has usually reached the mileage where they appear.
Compiled & reviewed by the VehicleFaults Research Team
The 2020 BMW X4 is 6 years old, so an average example has covered roughly 81,000 miles. At that mileage 6 of the documented faults are already due, so check those first.
Documented onset mileage is at or below the ~81k miles an average 2020 car has covered.
Front control arm bush knock over broken surfaces
Uneven wear from run flats and wide rear rubber
Timing chain and turbo actuator faults on diesels
Slow coolant loss and white crust around the expansion tank seams.
Juddering or binding sensation from the transfer case during tight turns.
Metallic rattling noise from the rear silencer on cold start.
Age, electronics and build-related issues that are not mileage-driven.
iDrive and driver assistance camera calibration faults
Active kidney grille shutters stuck, potentially triggering a check engine light.
Generate a tickable pre-purchase checklist for this exact year, mileage and variant · add photos and notes as you inspect.
Check this exact carYes with service history and honest tyre wear.
Ride harshness and premature tyre wear on large wheels.
Chain work on high mileage diesels.
The B58 3.0-litre petrol in the M40i is widely regarded as the most robust powertrain, provided it receives punctual servicing. For diesel buyers, the B47 2.0-litre in the xDrive20d is dependable but requires regular long motorway runs to prevent DPF and EGR blockages, which are common with urban use.
Yes, it is critical to fit BMW star-marked tyres and replace them in sets or axles to maintain identical rolling radiuses. Tread depth differences exceeding 2mm between the front and rear axles can cause severe wind-up in the VTG transfer box, leading to premature and costly drivetrain failure.
The panoramic sunroof drains are prone to blocking with leaves and debris. Water typically overflows into the headlining or runs down the A-pillars into the front footwells. Always lift the front carpets to check for dampness and inspect the boot floor cavities where sensitive electronic modules are housed.