2004 vs 2005 BMW 5 Series

Both years

• A failed brake booster All years One source so far

  What to check: Feel for a hard, stiff brake pedal.

  CarGurus lists failed brake boosters, which can stiffen the pedal dramatically, among the E60's typical problems.

  CarGurus

• Worn control arms and bushings All years

  What to check: Feel for vibration under braking and listen for clunks, and look for uneven tire wear.

  CarGurus lists broken or worn-out control arms, and Euro Premium Parts says worn front bushings cause vibration under braking.

  CarGurus, a seller's guide (unofficial)

• Early iDrive units that fail 2004–2007 One source so far

  What to check: Try every iDrive function, and watch for a blank screen or a unit that restarts itself.

  Euro Premium Parts says early CCC units are prone to failure and expensive to replace, and that the later CIC system is far more reliable.

  A seller's guide (unofficial)

• Cooling system parts All years

  What to check: Look for coolant leaks, and ask whether the water pump and thermostat have been replaced.

  Euro Premium Parts says radiator, expansion tank, water pump and thermostat failures are routine at around 80,000 to 100,000 miles on the sixes. CarGurus lists bad thermostats and fuel pumps too.

  CarGurus, a seller's guide (unofficial)

• Oil use and leaks on the V8s All years One source so far

  What to check: Look for blue smoke at start-up and oil around the timing covers.

  Euro Premium Parts lists worn valve stem seals, timing cover and alternator bracket gasket leaks, and high oil use even on well-kept cars.

  A seller's guide (unofficial)

• Battery drain and electrical faults All years

  What to check: Ask about battery warnings, and try the locks, lights, windows and climate control.

  Euro Premium Parts lists battery drain from the battery sensor or the trunk wiring, and CarGurus lists a variety of electrical issues and leaky sunroof seals.

  CarGurus, a seller's guide (unofficial)

Both years

• 08V384000 2004–2006

  Cracks can form in the front passenger seat's sensor mat, switching off the passenger airbags and lighting the warning lamp. Dealers rework the mat, and BMW extends the warranty on it. NHTSA

• 10V446000 2004–2010

  A check valve in the brake vacuum pump can leak oil, which over time can contaminate the brake booster. Dealers repair it. NHTSA

• 12V126000 2004–2010

  The positive battery cable's connector may have been fitted wrongly to the trunk floor, so its bolt can loosen and the connection overheat. Dealers inspect and secure it. NHTSA

Both years

Engines

2.5L inline-six (2004–2005) CarGurus, Edmunds, a published reference, 3.0L inline-six (2004–2005) CarGurus, Edmunds, a published reference, 4.4L V8 (2004–2005) Edmunds, CarGurus, a published reference

Transmissions

Six-speed manual Edmunds, Six-speed Steptronic automatic Edmunds, a published reference, Six-speed SMG automated manual Edmunds, CarGurus, a published reference

Drivetrains

Rear-wheel drive Edmunds, a published reference

Body styles

Sedan Edmunds, a published reference

Packages

Sport Package Edmunds, Cold Weather Package Edmunds

Both years

• Watch for: The SMG gearbox All years Walk away One source so far

  CarGurus lists trouble with the SMG transmissions among the E60's problems and says it is better just to stay away from them. CarGurus

• Watch for: An early 545i without full records 2004–2005 Walk away One source so far

  Euro Premium Parts says to avoid an early 545i unless it is fully documented. A seller's guide (unofficial)