The 740d is the performance diesel in BMW's sixth-generation 7 Series, pairing the twin-turbo B57D30T0 inline-six with 320 hp and 680 Nm through a ZF 8-speed automatic. It combines near-V8 acceleration with diesel economy, making it a popular choice among European executive drivers. The carbon-fibre-reinforced body and standard air suspension deliver a refined, composed ride. The B57 engine is widely regarded as one of BMW's most dependable modern diesels, though the flagship platform's electronics and air suspension add complexity that demands respect.· more· less
Air springs and compressor wear out, causing the car to sag or ride unevenly · more· less
All G11 models come with air suspension as standard. The air springs develop leaks over time, typically after 80,000-120,000 km or 6-8 years. When a spring leaks, the compressor runs continuously to compensate, overheats, and eventually burns out. A single OEM air strut costs approximately €700-900 for the part. The compressor with bracket runs €400-800 aftermarket. With labor, replacing a single strut plus compressor typically costs €1,500-2,500. If multiple struts fail simultaneously (common as they age together), costs escalate quickly to €3,500-4,500. BMW extended the warranty on G11 air struts in some markets (8 years / 80,000 miles). Always check whether this applies. Prevention: listen for the compressor running excessively (whirring noise from the trunk area) and inspect struts for oil misting.
AdBlue/SCR system faults (NOx sensor, pump, heater)
€400 - 1,8002 of 8
NOx sensors and SCR components fail, triggering restricted-start countdown warnings · more· less
The B57 uses an AdBlue (urea injection) system for Euro 6 compliance. NOx sensors are the most frequent failure point, typically between 50,000-100,000 km. A single NOx sensor replacement costs €350-600 including labor. The SCR pump can fail and costs €600-1,200 to replace. The AdBlue heater (prevents freezing) can also fail at €400-800. Symptoms include engine management light, AdBlue system warnings, and eventually a restricted-start countdown that limits the number of remaining engine starts before the car refuses to run. Use only sealed, high-quality AdBlue, top up regularly, and address warning lights promptly. This is a common issue across all BMW B57 diesel applications, not specific to the 740d.
EGR cooler leak (fire risk recall)
€0 - 2,5003 of 8
EGR cooler can leak coolant internally, causing intake manifold damage or fire risk · more· less
BMW issued a major recall (initially 2018, expanded 2021, further extended 2024) affecting approximately 800,000 diesel vehicles worldwide, including G11 740d models with the B57 engine. The EGR cooler can leak glycol coolant into the intake system, where it mixes with diesel soot at high temperatures and can cause smoldering, intake manifold melting, or in rare cases a fire. The recall covers free EGR cooler and intake manifold replacement at BMW dealers. However, the recall has been expanded multiple times as earlier fixes proved insufficient. An optimized replacement cooler from a different supplier was only introduced in 2022. If the car is not covered or the recall was not completed, repair costs are €1,500-2,500. Always verify recall completion with VIN before purchase. This is one of the most critical pre-purchase checks for any used BMW diesel of this generation.
Oil filter housing gasket leak
€500 - 1,2004 of 8
Gasket between oil filter housing and engine block degrades, causing oil and coolant leaks · more· less
The oil filter housing gasket is a known weak point on BMW inline-6 engines. It sits in a high-heat area and the gasket material degrades over time. Both oil and coolant pass through this housing, so a failed gasket can cause either or both fluids to leak. Typically appears between 80,000-130,000 km. Repair costs €500-800 at an independent specialist or €800-1,200 at a BMW dealer. The repair involves removing the intake manifold for access, which drives up labor time. If coolant mixes with oil due to this leak, it can cause bearing damage if not addressed promptly. It is advisable to replace the valve cover gasket at the same time if both show signs of age.
ZF 8HP mechatronic / valve body wear
€1,200 - 3,5005 of 8
Internal seals harden and leak, causing rough shifting or gear selection faults · more· less
The ZF 8HP is one of the most reliable modern automatic transmissions, but it is not immune to problems. The mechatronic unit contains rubber seals and sleeves that harden over time, especially if transmission fluid is never changed. Despite BMW originally claiming the fluid was a lifetime fill, ZF recommends servicing every 80,000-100,000 km. Symptoms include harsh shifts when cold, hesitation at low speeds, or transmission warning lights. One G11 740d owner on a specialist forum reported a complete mechatronic failure at around 150,000 km, costing £2,000 for replacement plus a full gearbox service. Valve body repair costs €800-1,500 at a specialist, while full mechatronic replacement runs €2,000-3,500. Regular fluid changes (€250-400) every 80,000 km significantly reduce this risk.
DPF clogging from short-trip driving
€500 - 2,5006 of 8
Diesel particulate filter clogs without regular motorway driving for regeneration · more· less
The DPF requires high exhaust temperatures sustained over 20-30 minutes to complete regeneration cycles. Cars used primarily for short urban trips accumulate soot faster than it can be burned off. Symptoms include DPF warning light, reduced power, and eventually limp mode. Professional cleaning costs €200-500 and can restore function if caught early. Full DPF replacement costs €1,500-2,500 including labor. This is largely preventable with regular motorway driving of at least 30 minutes per week at sustained speed. The B57's improved thermal management makes it somewhat less prone than older N57 engines, but the issue remains common on any diesel used predominantly in urban traffic.
Oil residue from the turbocharger and EGR system deposits carbon on the intake manifold swirl flaps over time. The engine ECU detects restricted movement and triggers a warning. This typically becomes noticeable after 100,000-150,000 km. Symptoms include reduced power, poor fuel economy, and engine warning lights. Professional cleaning costs approximately €400-600. Some specialists offer permanent swirl flap removal with blanking plates at similar cost, which prevents recurrence. The B57 is somewhat less prone to this than older N57 engines, but it still occurs with age, especially on cars that see frequent short-trip or city driving.
Electrical system glitches and battery drain
€200 - 8008 of 8
Complex electronics cause intermittent faults, iDrive freezes, and parasitic battery drain · more· less
The G11 has extensive electronic systems that can develop intermittent faults. Common issues include iDrive screen freezes (usually resolved by firmware update), door latch malfunctions in cold weather, window regulator failures, and parasitic battery drain from modules that fail to enter sleep mode. A healthy G11 in full sleep mode should draw under 50 mA; anything above 80 mA signals a parasitic drain that needs investigation. The AGM battery itself costs €250-400 to replace. Individual module repairs vary from €200-800. Many issues are resolved by software updates at a BMW dealer. Cars that sit unused for more than a week frequently experience flat batteries. A quality trickle charger is strongly recommended for infrequent use.
Strong engine, but luxury platform complexity demands budget
The twin-turbo B57 diesel is one of BMW's most capable and reliable modern engines, comfortably reaching 200,000+ km with proper maintenance. However, the G11's standard air suspension, extensive electronics, and emissions equipment (AdBlue, DPF, EGR) add layers of cost that make repairs significantly more expensive than a comparable 5 Series. Budget for air suspension wear as a near-certainty on higher-mileage examples, verify the EGR cooler recall has been completed, and ensure the car has been used for the regular motorway driving that diesel emissions systems require.
Service history
Complete BMW dealer or specialist records essential. Verify oil changes every 12 months or 15,000 km, and that ZF gearbox fluid was changed at 80,000 km.
Tires
Check tread depth, age (date codes), and uneven wear. Staggered setups (wider rear) wear unevenly if alignment is off.
Cold start
Start the engine completely cold. Listen for any unusual diesel knock, excessive smoke, or extended cranking time.
Test drive
Drive for at least 30 minutes including motorway speeds. The car must get fully warm to reveal gearbox, suspension, and emissions system issues.
Specific for this vehicle
Check air suspension ride height on all four corners
Park on level ground and visually check the car sits evenly. Start the engine and listen for the compressor running (whirring from the trunk). Excessive compressor activity indicates a leak.
Verify EGR cooler recall completion
This is a critical safety recall affecting most G11 diesels. Contact BMW with the VIN before viewing. Do not buy without confirmation that the latest recall remedy has been applied.
Check AdBlue system status on dashboard
Look for any AdBlue warning messages. Check the AdBlue level is adequate. Ask about any previous NOx sensor or SCR component replacements.
+ 3 more checksShow less
Inspect under the engine for oil and coolant leaks
Check around the oil filter housing and valve cover for seeping oil or coolant. Look at the ground under the engine after a test drive for fresh drips.
Test all electronic systems thoroughly
Operate every button, screen, seat adjustment, climate zone, and driver assist feature. Check iDrive responds without freezing. Test all door latches open and close cleanly.
Check DPF regeneration history with diagnostic tool
A BMW-compatible diagnostic tool can show DPF soot loading and regeneration frequency. High soot levels or infrequent regeneration indicate short-trip use that accelerates wear.
Starter motor fire risk (selected G11/G12 models, 2025 recall)Verify with VIN
Driveshaft connection flange durability (2016-2017 select models)Verify with VIN
The EGR cooler recall is critical and has been expanded multiple times since 2018. BMW's initial fixes proved inadequate, and an optimized replacement part from a different supplier was only introduced in 2022. Contact BMW with the VIN to verify the latest recall remedy has been applied, not just an earlier incomplete fix. Also check whether the starter motor recall applies to your specific car.
Warranty Status
Factory warranty (2 years, pre-Nov 2016)Expired on all pre-Nov 2016 production cars
Factory warranty (3 years, from Nov 2016)Expired on all models produced after Nov 2016
Air suspension extended warranty8 years / 80,000 miles in some markets. Verify with BMW.
BMW extended warrantyAvailable through BMW dealers, typically up to 2 years additional
All G11 740d models are now outside their original factory warranty. The 2+1 warranty (3 years total, introduced November 2016) also expired for all G11 production. Check whether the air suspension extended warranty applies to your specific car, as this can save significant repair costs on strut replacements.
Sources: Research draws on model-specific owner forums and owner communities, recall information from official authorities, German automotive press, and multiple workshop cost references cross-checked against each other.
This report is for informational purposes only and does not constitute professional advice. Estimates may be inaccurate. Always have a qualified specialist inspect the vehicle before purchase. We accept no liability for decisions made based on this information.
