BMW 5 series 2003 2.5 petrol service and maintenance

Engine oil

Engine oil capacity: 6.5 litres (6.9 quarts)
Oil change interval is 10,000 km or one year, whichever comes first.
Recommended oil type (Oil Viscosity Classification SAE) is 5W-30

Air filter

Air filter change interval is 20,000 km.
After prolonged driving in particularly dusty conditions, it is advisable to check the condition of the air filter earlier and replace it if the filter is visibly dirty.

Fuel filter

BMW 5 series 2.5 petrol fuel filter change interval is 60,000 km

Spark plugs

Replacement interval for spark plugs is 60,000 km.

Timing chain

There is no manufacturer specified replacement interval for the engine timing chain on BMW 5 series 2003 2.5 petrol, expecting it to last until the engine is overhauled (approximately 220,000 km - 370,000 km).
Based on real life experience, the BMW 525i 2003 timing chain change interval is approximately 120,000 km as at this mileage it may become overstretched and require replacement, so it is recommended to check the condition of the chain periodically after this mileage is reached and replace the timing chain if it becomes excessively stretched or if unusual engine noises occur.

Serpentine (drive) belt

BMW 525i serpentine or alternator belt replacement interval is 100,000 km, but in reality it may have a shorter service life and it is advisable to pay close attention to the condition of the belt or to replace it after an interval of 60,000 km.

Engine coolant

Engine coolant (antifreeze) recommended replacement interval for BMW 5 series 2.5 petrol is 60,000 km or 4 years, whichever comes first.
Coolant capacity is 9.8 litres

Valve stem oil seals replacement

Valve stem oil seals replacement for BMW 5 series 2.5 petrol is recommended every 120,000 km.
Due to the high operating temperatures of the engine, valve seals often do not last more than 120,000 km. If valve seals are not replaced in time, there is a risk of damage to the catalytic converter, which can lead to more serious engine damage.

VANOS solenoid valves replacement

VANOS solenoid valves replacement for BMW 5 series 2.5 petrol is recommended every 60,000 km.
In order to avoid expensive repairs, it is recommended to carry out an inspection of the VANOS oil supply system with replacement of the solenoid valves and flushing of the return valves once every 60-80 thousand km.