"Is the 6 Serisi 640d reliable, and what should you check?"
Most commonly reported issue when buying a used BMW 6 Series 640d 2020 (F06 / F12 / F13 / LCI): Timing chain wear reports (rare). Also, EGR valve/cooler clogging is frequently reported.
Engine: B57
B57D30B · 640d · Used in this car from 2019-2023
Known engine issues
Swirl flapsThe most known problem of this diesel is contamination of the intake manifold and its swirl flaps, resulting in power loss and unstable engine operation. In severe cases, the flap axle breaks and the manifold must be replaced.
Timing chain stretchGenerally, the timing chain of modular series engines lasts 200-250 thousand km or more, but for powerful diesels with huge torque, replacement by 100,000 km is not uncommon.
Oil leaksOn the specialized forum, there are many complaints about leaks from the pressure sensor and valve cover. If replacing the cover assembly does not help, the gasket under the camshaft bed leaks.
+2 more issues on the engine detail page
Known issues and risks
Listed from most frequently reported, each with its source.
Timing chain wear reports (rare)
Often reported
Some reports indicate wear or abnormal noises from the timing chain on the 3.0 engine, but the newer B57 generation offers improved reliability.
Timing chain
EGR valve/cooler clogging
Often reported
The 3.0 diesel engine (B57 variants) has complex EGR circuits. Short-distance city driving can cause carbon deposits in EGR passages and coolers, leading to idle fluctuation, power loss, increased exhaust smoke, and warning lights.
Exhaust Emissions
High-pressure injector sensitivity (piezo)
Often reported
The B57 engine family uses piezoelectric injectors and ultra-high-pressure common rail systems. These components are very sensitive, but poor fuel quality or irregular maintenance can lead to injector failures or malfunctions.
Fuel System
BMW 6 Serisi 640d technical specs
BMW 6 Serisi 640d (2020): boot 600 L; fuel use 5,6 l/100 km (urban 6,9 l/100 km · extra-urban 4,8 l/100 km); 0–100 in 5.3 s.
Boot capacity
600 L
Fuel consumption
5,6 l/100 km (urban 6,9 l/100 km · extra-urban 4,8 l/100 km)
What should I look for when buying a BMW 6 Series 640d?+
When buying a 2020 640d, check service history, test drive, and look for engine/transmission warnings. Most commonly reported issues: timing chain wear reports (rare); EGR valve/cooler clogging; high-pressure injector sensitivity (piezo).
What are the common problems of the BMW 6 Series 640d?+
Rather than a simple yes/no, it's best to weigh the proven pros and cons together. This page lists 3 verified findings.
How does Carbeak collect data?+
The cards on this page are derived from Difetti fault database records; source and target vehicles are verified for brand, fuel, engine, and generation match. Topics with insufficient evidence are not shown.