BMW xDrive40d
Modular straight-six diesel with up to 340 hp in the M version. Extremely smooth and torquey; DPF and SCR catalytic converter are the main wear points.
Authoritative, but heavy
Powerful inline-six in a heavy saloon — authoritative on the motorway, but no corner carver.
Engine Weaknesses 5
EGR cooler can fail and allow coolant into the intake tract. Documented cases of engine damage shortly after EGR cooler replacement.
Symptoms: Coolant loss, white smoke, engine check light, overheating
Early B57 models (from about 2015/16) show chain elongation with rattling noises on startup. Timing chain replacement requires engine removal. Repair costs comparable to the N57. Significantly rarer from 2018 models.
Symptoms: Metallic rattling on cold start, especially at low temperatures; subsides after warm-up; in extreme cases engine stumble
Bearing damage occurs in the bi-turbo system at higher mileage. Turbine blades can break off and cause engine damage. Frequently encouraged by insufficient oil change intervals.
Symptoms: Whistling or howling under load; blue exhaust smoke; power loss; MIL; in extreme cases sudden power loss from turbo failure
The EGR valve cokes up with frequent short-trip driving and becomes stiff. Stumbling on cold start is characteristic. BMW carried out a voluntary service action.
Symptoms: Stumbling and hesitation on cold start until the engine warms up; power loss; 'Drivetrain malfunction' message; black smoke; EGR valve fault
NOx sensors and SCR dosing unit fail after about 100,000 km or through AdBlue crystallisation. Fault code 26F500 is typical. BMW repairs often cost 2,000–4,000 EUR as entire systems are replaced.
Symptoms: MIL with message 'AdBlue system faulty' or 'Emission system fault'; fault code 26F500; engine runs normally but warning persists
Vehicle Weaknesses 5
The X6 G06 (production from June 2022) is affected by the major BMW brake system recall. Signal faults in the IBS can cause ABS and DSC to fail. BMW replaces the brake system free of charge (Recall 0034670200).
The axle suspension on the X6 G06 is a frequent cause of defects at inspection. The high vehicle weight above 2 tonnes stresses suspension components disproportionately.
Oil loss occurs on the X6 across all model years and regularly causes problems at emissions tests. The six-cylinder N58/S58 petrol and V8 engines are particularly affected.
The electric tailgate on the X6 frequently shows hydraulic strut or control unit defects. Problems typically occur from 40,000–60,000 km.
The high kerb weight of the X6 G06 at over 2.1 tonnes causes above-average rapid wear of brake discs and pads. Maintenance costs are significantly higher than on comparable vehicles.
Reports & Tests
37 owner complaints filed with NHTSA (2019–2026). Most reported: Brakes (16), Electrical (7), Other (6).