BMW 640d
Successor to the M57 with aluminium crankcase and piezo injectors. Extremely smooth and torquey. EGR cooler, DPF and turbocharger are the main wear points.
Diesel GT
Diesel R6 in the sports coupe — surprisingly enjoyable, with mountains of torque.
Engine Weaknesses 6
The N57D30 timing chain can break; plastic guide rails break and block the oil pump. Damaged valves and bearing shells follow. No reliable audible advance warning.
Symptoms: Rattling or clattering on cold start (warning sign!). Often no advance warning — engine dies suddenly.
Main bearings and connecting rod bearings wear from around 150,000–200,000 km. The aluminium crankcase with steel bearing housings has differing thermal expansion coefficients. Bearing shells can spin — catastrophic engine damage.
Symptoms: Dull knocking or hammering from the engine block under load; oil pressure warning; metallic tapping; engine oil with metallic particles
Leaking EGR coolers cause gradual coolant loss. BMW carried out a voluntary service campaign. Overheating from coolant shortage risks a cracked cylinder head. Repair costs without goodwill are very high.
Symptoms: Gradual coolant drop with no visible external leak; white-blue exhaust smoke; sweet smell inside the cabin; engine warning light; overheating warning
The N57 bi-turbo system shows bearing wear at high mileage. Broken turbine blades can destroy the cylinder bores and cause total engine failure. Repair costs often exceed €8,000.
Symptoms: Whistling or rattling from the turbo area; sharply reduced power delivery; blue or white exhaust smoke; engine warning light; limp mode
Diesel injectors wear at high mileage. Diagnosis via cylinder balance test and return flow measurement. Individual injector replacement possible at around €450 including installation.
Symptoms: Rough running especially at idle (engine "runs like a tractor"), hesitation, increased fuel consumption, smoke clouds.
Glow plugs and the glow plug control unit fail regularly at higher mileages. The fault memory often shows all plugs as defective even though only the control unit is faulty. Cold-start problems and DPF overload possible in frost.
Symptoms: Glow plug warning light stays on; difficult starting below 5°C; slight judder in the first minute after cold start
Vehicle Weaknesses 19
The auxiliary damper and its dust cover at the rear axle wear prematurely and become oil-soaked. As EDC dampers are only available as BMW originals (~1,800 € per side), repair is extremely expensive.
On diesel engines (640d), the EGR cooler can leak and lose coolant. Combined with soot deposits in the intake tract, glowing particles can form that may cause engine fire in extreme cases. BMW conducted a recall.
Identical issue to the F06/F13: the auxiliary damper and dust cover at the rear axle wear and become oil-soaked. EDC dampers are only available as BMW originals (~1,800 € per side).
On the 640d diesel (N57), the EGR cooler can lose coolant. Soot deposits in the intake can produce glowing particles, posing a fire risk in extreme cases. BMW has carried out recalls and service campaigns.
Both the N55 (640i) and N63 (650i) in the F12 are known for early electric water pump failures.
Same issue as on F06/F12: the auxiliary damper dust cover at the rear axle tears and EDC dampers become oil-soaked. Original dampers cost ~1,800 € per side; always replace in pairs.
On the 640d (N57), the EGR cooler can lose coolant; soot particles in the intake can create a fire risk. BMW has conducted service campaigns and recalls.
N55 (640i) and N63 (650i) in the F13 coupé are known for electric water pump failures. Possible from 100,000–150,000 km.
The standard rear air suspension suffers from porous air bellows that lose pressure. If not caught in time the compressor overloads and fails too. Complete system failure can cost 5,000–8,000 €.
On diesel variants of the G32 (630d, 640d), the EGR cooler can leak and lose coolant. BMW has conducted multiple recalls and service campaigns (extended through to 2022).
The frameless windows on the F13 coupé tend to produce wind noise, especially at the driver's door from around 130 km/h. New door seals and window guides help.
The N63 in the 650i F13 suffers from elevated oil consumption caused by porous valve stem seals, resulting from the extreme heat of the hot-V turbos.
The optional panoramic glass sunroof has 4 drain channels that block with leaves and dirt. Water then runs into the cabin blower or reaches the boot.
The optional dual-axle air suspension with adaptive dampers shows similar problems to the F series: dampers become oil-soaked, fault codes appear.
The frameless door windows on the Gran Coupé tend to produce wind noise at the driver's door from around 130 km/h. The window seals don't sit flush due to minor body flex.
The NBT infotainment system crashes sporadically and restarts. Stability deteriorates especially after smartphone OS updates. A vehicle software update usually helps.
On older examples seat rails loosen, causing rattling and movement in the seat. The frameless doors allow torsional forces on the body that cause creaking.
The NBT infotainment system restarts sporadically or permanently shows the boot screen. Bluetooth/USB stability deteriorates especially after phone OS updates. A BMW software update usually helps.
The G32's power tailgate can be disrupted by faulty spindle drives. After drive replacement, the tailgate control unit must learn the new position.