BMW 8er G15

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

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