Does flushing the engine before an oil change make sense?

Flushing the engine before an oil change is a topic that divides mechanics. In some situations it helps, in others it can do harm.

When does flushing make sense?

• When we don’t know the car’s service history
• When deposits and sludge in the engine are suspected
• After very overdue oil
• When switching to a different oil type in a neglected engine

When is it better to skip it?

In high-mileage engines with a thick layer of deposits, flushing can dislodge contaminants that then clog the oil channels. In a regularly serviced car it’s usually not needed.

The best prevention is simply a regular oil change — then flushing isn’t needed at all.