How Do You Remove Engine Oil Sludge?

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To remove engine oil sludge, use an approved sludge-removing additive, such as a synthetic oil with sludge remover or a flushing oil concentrate. Applying these additives and correctly flushing the engine effectively removes engine oil sludge.

  1. Change oil and filter

    Replace the filter with a new one, and add the sludge-removing agent to the crankcase. If the vehicle recently had its oil changed and is using an approved synthetic oil, the additive can be poured into the crankcase without first removing the oil.

  2. Start the engine, and run a check

    Start the engine, and let it run for 10 minutes to blend the additive properly. Drive the vehicle 1,000 miles if using conventional oil and 1,500 miles if using synthetic oil. After these distances, change the oil filter and drain the oil by placing a drain pan below the oil pan and unscrewing the oil plug.

  3. Refill the engine’s crankcase

    Fill the engine’s crankcase with a premium synthetic motor oil that meets the requirements of the vehicle. The vehicle’s manual indicates what type of motor oil is best for the vehicle. Use a high-grade synthetic oil that resists oxidation and features good dispersant properties. Continue to change the oil and filter after 3,000 miles.