BMW 5 Series 525d.
What to Check Before Buying.

The BMW 5 Series 525d suits business professionals and family buyers seeking executive comfort with impressive fuel economy. This diesel variant delivers strong mid-range performance ideal for motorway commuting whilst returning 45-55 mpg in real-world driving. The 525d offers an excellent balance between the entry-level 520d and pricier 530d, providing ample power without the higher running costs. When buying used, check the service history meticulously as these engines require regular oil changes using the correct BMW Longlife specification to prevent timing chain issues, particularly on pre-2013 models. Inspect for blue smoke on startup which indicates turbo or injector problems. The diesel particulate filter can become blocked on cars used mainly for short journeys, so verify the previous ownership pattern and look for dashboard warning lights. Check all electrical functions including the iDrive system, parking sensors, and adaptive headlights as repairs can be costly. A comprehensive inspection of suspension components is essential as worn bushes and dampers are common on higher mileage examples, affecting the renowned 5 Series ride quality.

The average used car has 3+ known model faults the seller won't mention.