Six common maintenance mistakes

The six common mistakes

• Checking viscosity such as 5W-40 but ignoring API, ACEA or JASO
• Assuming higher numbers and thicker oil always protect better
• Adding extra oil or additive in the hope of a stronger effect
• Topping up without changing the oil and filter on schedule
• Treating dark oil as automatic proof of poor quality
• Relying only on additives after warning lights, noise or vibration appear

A simple order to follow

Identify the vehicle, year and engine first, then note the manual's viscosity and performance requirements. Only after every requirement is met should you compare brands, price and operating conditions.

Find the cause of a fault first

Maintenance products cannot replace fault diagnosis. Warning lights, obvious leaks, unusual noise, overheating or an abnormal brake pedal call for a technician's inspection before further do-it-yourself attempts.