BMW 7er G11

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.

• !! EGR cooler failure from 120,000 km

  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
  600–2,000 $
  Ad BMW B57 EGR-radiator
• !! Timing chain elongation on early models from 130,000 km

  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
  1,500–4,000 $
  Ad B57 timing chainB57D30 timing chainB57 chain tensioner
• !! Turbocharger bearing damage at high mileage from 180,000 km

  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
  1,500–8,000 $
  Ad B57 turbochargerB57D30 turbochargerBMW 3.0d Lader

+ 2 more engine weaknesses + vehicle weaknesses

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.

• !! EGR cooler failure from 120,000 km

  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
  600–2,000 $
  Ad BMW B57 EGR-radiator
• !! Timing chain elongation on early models from 130,000 km

  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
  1,500–4,000 $
  Ad B57 timing chainB57D30 timing chainB57 chain tensioner
• !! Turbocharger bearing damage at high mileage from 180,000 km

  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
  1,500–8,000 $
  Ad B57 turbochargerB57D30 turbochargerBMW 3.0d Lader

+ 2 more engine weaknesses + vehicle weaknesses

Closed-deck aluminium block as standard — a feature normally reserved for racing engines. Water-cooled turbo with mechanical wastegate linkage that rattles at cold start — by design, not dangerous. Barely audible at idle; from 3,000 rpm a rich, deep six-cylinder thrust builds linearly to 6,500. The B58 sounds fuller than the S55 from outside — but inside the motorsport aggression is absent. Dual injection (direct + port) reduces intake valve carbon build-up significantly. The PCV membrane in the valve cover is the known weakness: BMW had to extend the warranty to 15 years. Plastic oil filter housing cracks around 100,000 km — coolant mixes into oil, act immediately. Oil changes every 10,000 km; inspect the cooling system from 70,000 km. Tuning: Stage 2 brings 500 hp — the closed deck makes it possible.

• !! Oil filter disintegrates — engine damage risk from 30,000 km

  On B58-equipped M140i/M240i the oil filter can disintegrate on first change and distribute filter material through the oil circuit. BMW covers the costs with proven service history.

  Symptoms: Oil pressure warning, metallic noises, engine damage after oil change
  100–8,000 $
  Ad BMW B58 oil filterBMW M140i oil filter
• !! Plastic oil filter housing cracks — coolant/oil mixing from 100,000 km

  The plastic oil filter housing becomes brittle from heat cycling and cracks — often during oil changes from overtightening the filter cap. Coolant and oil mix; engine damage likely if unnoticed.

  Symptoms: Milky oil on the filler cap, coolant loss without visible leak, oil pressure warning, coolant level drops slowly
  400–1,500 $
  Ad BMW B58 oil filter housing KunststoffBMW B58 oil filter housing 11428637215B58 oil filter housing replacement
• !! PCV valve / valve cover membrane failed from 80,000 km

  The PCV membrane in the integrated valve cover tears or hardens from heat cycles. Crankcase builds positive pressure, oil is forced through seals. BMW extended the warranty to 15 years/150,000 miles.

  Symptoms: Whistling or squealing from the engine bay, white or blue smoke, rough idle, oil in the charge pipe or air filter
  800–2,500 $

+ 9 more engine weaknesses + vehicle weaknesses

Modular four-cylinder turbo and workhorse of the current BMW lineup. Wide power range from 135 to 306 hp (M135i/M235i). Structurally the best four-cylinder petrol BMW has ever built: timing chain at front, closed oil circuit, Valvetronic variable valve lift. Oil consumption stays under control when BMW-spec oil (LL-01 or LL-17FE+) is used. Typical wear items are the electric water pump (from around 80,000 km) and the high-pressure pump with direct injection. Not an engine to fear — but BMW service intervals are too long; those who care for their B48 change oil every 10,000-12,000 km.

• !! Timing chain guide rail breaks from 60,000 km

  Timing chain guide rail can break; chain jump and engine damage follows. More common on early production years and with spirited driving.

  Symptoms: Rattling, clattering from the engine, sudden power loss, engine damage
  2,000–4,000 $
  Ad BMW B48 timing chainBMW B48 GleitschieneBMW B48 chain tensioner
• !! Oil filter housing leaking — coolant loss from 60,000 km

  Oil filter housing with integrated oil/water heat exchanger leaks. Coolant loss and overheating risk from about 60,000 km.

  Symptoms: Coolant level warning, oil puddle under engine, overheating
  400–1,200 $
  Ad BMW B48 oil filter housingBMW B48 heat exchanger11428643747
• !! Coolant bleed line at cylinder head breaks from 70,000 km

  A plastic bleed line between the cylinder head and expansion tank becomes porous and breaks. Coolant loss follows; the mounting location is difficult to access, so labour costs dominate.

  Symptoms: Dropping coolant level; coolant warning on the instrument cluster; faint sweet smell; no visible puddle under the car
  300–700 $
  Ad BMW B48 coolantleitung cylinder headBMW B48 breather line

+ 6 more engine weaknesses + vehicle weaknesses

The Technical Update resolved the worst problem of the first generation — away from piezo injectors, new piston rings, Valvetronic added. The character remained: a commanding V8 that is barely audible in Comfort mode and sends a powerful growl from afar in Sport. Hot-V heat soak remains by design — short oil change intervals (max. 7,000 km) are mandatory, not an optional extra.

• !! Timing chain wear at high mileage from 130,000 km

  The timing chain system remains the weak link in the TU as well. Plastic guide rails degrade. Preventive replacement from 120,000–150,000 km is advisable. Repair requires complete engine removal (~40 labour hours).

  Symptoms: Rattling on cold start, engine warning light, in extreme cases loud clattering and engine failure
  4,500–8,000 $
  Ad timing chain N63TU settiming chainnführung N63TUchain tensioner N63B44TU
• !! Valve stem seals — oil consumption despite revision from 130,000 km

  Despite revision, valve stem seals can wear at high mileage. Oil consumption of 0.5–1 L/5,000 km is reported by TU owners. Significantly better than the original N63, but not fully eliminated.

  Symptoms: Slightly elevated oil consumption, occasional light blue smoke on cold start, oil level warning earlier than expected
  3,290–3,800 $
  Ad valve stem seal N63TUvalve stem seal N63B44TU setpiston rings N63TU
• !! Turbo bearing damage from Hot-V heat build-up from 150,000 km

  Hot-V design remains structurally prone to oil carbon build-up in the turbo feed lines. Switching the engine off immediately after hard driving promotes deposits and premature turbo wear.

  Symptoms: Power loss under load, occasional hissing or whining from the engine bay, rarely blue smoke after a motorway run
  2,000–5,000 $
  Ad turbocharger N63TU leftturbocharger N63TU rightÖlzufuhrleitung Turbo N63TU

+ 2 more engine weaknesses + vehicle weaknesses

Third-generation hot-V eight-cylinder — turbos sit INSIDE the cylinder V, not on the sides. This shortens exhaust paths and improves response but creates extreme temperatures in the engine valley. Electric wastegates react in milliseconds, 350 bar injection and forged internals. In Sport+ with the exhaust flap open, a deep bass-heavy V8 growl with turbo whoosh and pops on throttle lift — less theatrical than AMG but more refined. Noticeably sharper than TU/TU2, and the notorious original N63 with its oil issues is light years away. Stage 1 software tune realistically yields 570+ HP on stock turbos. Most reliable N63 variant, but the hot-V architecture demands discipline: short oil change intervals (max 5,000 miles) with 0W-40 are mandatory, always let the engine idle after hard driving. Check starter motor recall (overheating/fire risk) at the dealer.

• !! Recall: Starter Motor — Overheating with Fire Risk

  Repeated start attempts can cause the starter motor to overheat from electrical overload and ignite combustible materials in the engine compartment. Affects over 340,000 BMW vehicles (2019–2021). Free repair at BMW dealer.

  0–0 $
• !! Valve stem seals — residual risk at high mileage from 160,000 km

  The fundamental design with valve stem seals is retained. At very high mileages (>150,000 km) and aggressive use the seals can suffer thermal wear. Repair costs €3,300–3,800 (approx. 6–8 hours' work, engine removal required).

  Symptoms: Increased oil consumption at very high mileages, slight blue smoke on cold start or after extended standstill, oil deposits in the exhaust
  3,290–3,800 $
  Ad valve stem seal N63TU3valve stem seal N63B44TU3 set
• !! Timing chain guides at risk from oil quality degradation from 150,000 km

  The plastic timing chain guide rails are sensitive to degraded engine oil. Extended oil change intervals (BMW Longlife) accelerate degradation. Complete engine removal (~40 labour hours) required; preventive replacement at >150,000 km is advisable.

  Symptoms: Rattling on cold start, engine warning light, occasionally loud clattering with heavily degraded oil
  4,500–8,000 $
  Ad timing chain N63TU3 settiming chainnführung N63B44TU3chain tensioner N63TU3

+ 6 more engine weaknesses + vehicle weaknesses

The N74B66 is an N74B60 with more stroke — 6.6 instead of 6.0 litres; otherwise identical architecture. Two DME control units, two high-pressure pumps, two turbochargers. The power increase to 585 or 609 hp comes not from higher boost but from the larger displacement — the engine runs more relaxed than comparably powerful six-cylinders. 850 Nm from 1,550 rpm available immediately. In everyday use barely audible; on the motorway almost frighteningly fast. The solenoid injectors of the later models are significantly more reliable than the first piezo units. Observe all service intervals strictly — short oil changes (maximum 15,000 km) and cool-down after hard use are not a recommendation but a requirement for BMW's last V12.

• !! Bi-turbo bearing wear at high mileage from 150,000 km

  The bi-turbochargers of the N74B66 show bearing wear at higher mileages, especially with irregular oil changes. Failing to let the engine cool after full-load driving accelerates bearing wear considerably.

  Symptoms: Whistling or whining under acceleration, bluish exhaust smoke, power drop, boost pressure faults.
  3,000–9,000 $
  Ad turbocharger N74B66Turbo 760i N74Lader BMW V12 Biturbo
• !! Early piezo injectors leaking — full set required from 60,000 km

  Early N74B66 units (2016–2018) used piezo injectors prone to internal leakage. Conversion to solenoid type recommended. Mixing old and new injectors is not permissible — full set required.

  Symptoms: Rough running on individual cylinders, misfires, increased fuel consumption.
  3,500–9,000 $
  Ad fuel injector N74B66fuel injector BMW M760Li setPiezo fuel injector V12
• !! Cooling system ageing — thermostat and water pump from 120,000 km

  The elaborate cooling system of the N74B66 V12 uses multiple thermostats and an electric auxiliary water pump. Plastic thermostat housings and seals fail with age. Coolant loss is increasingly common.

  Symptoms: Coolant level drops without visible leak, engine temperature warning, steam from under the bonnet.
  500–2,000 $
  Ad thermostat N74B66water pump BMW 760icoolantleitung V12

+ 8 more engine weaknesses + vehicle weaknesses