Skip to main content

The used car I bought wasn’t properly maintained, how can I get rid of sludge buildup?

The 2000 Jeep Cherokee I recently purchased with almost 232,000 kilometres on it clearly did not receive proper maintenance. After the replacement of a leaky valve cover gasket, my mechanic indicated that it was super gunked up. He suggested an engine flush and a fresh oil change. The reviews I've read state that engine flushes are a bad idea and can cause extensive damage to your engine. – Beth D.

Yes, your Cherokee's power plant is exhibiting excessive sludge buildup from a lack of oil changes, and an oil flush is a questionable solution, one that would possibly aggravate the situation.

As engine oil becomes severely contaminated, its viscosity migrates from that of a fluid into a solid, ceasing to flow, hardening into a solid-like mass commonly referred to as "sludge."

Story continues below advertisement

This build up occurs relatively slowly. Chemicals that cause rapid removal or loosening of that sludge may dislodge a large particle.

Oil manufacturers design products with additives intended to breakdown and suspend contaminants that can be safely delivered to the filtration system. When a large particle breaks off, the best we can hope for is that it gets caught by the filter, but it can also get lodged – blocking an important oil passage, ultimately causing engine failure.

I consider engine flushes to be periodic maintenance items intended for engines that are in relatively decent condition. I would ask your mechanic for a review of your situation. Since he is recommending this service, perhaps the sludge isn't as bad as initially thought, otherwise caution is in order.

Lou Trottier is owner-operator of All About Imports in Mississauga. Have a question about maintenance and repair? E-mail globedrive@globeandmail.com, placing "Lou's Garage" in the subject area.

Like us on Facebook

Follow us on Instagram

Add us to your circles

Story continues below advertisement

Sign up for our weekly newsletter

Report an error Editorial code of conduct
Due to technical reasons, we have temporarily removed commenting from our articles. We hope to have this fixed soon. Thank you for your patience. If you are looking to give feedback on our new site, please send it along to feedback@globeandmail.com. If you want to write a letter to the editor, please forward to letters@globeandmail.com.

Welcome to The Globe and Mail’s comment community. This is a space where subscribers can engage with each other and Globe staff. Non-subscribers can read and sort comments but will not be able to engage with them in any way. Click here to subscribe.

If you would like to write a letter to the editor, please forward it to letters@globeandmail.com. Readers can also interact with The Globe on Facebook and Twitter .

Welcome to The Globe and Mail’s comment community. This is a space where subscribers can engage with each other and Globe staff. Non-subscribers can read and sort comments but will not be able to engage with them in any way. Click here to subscribe.

If you would like to write a letter to the editor, please forward it to letters@globeandmail.com. Readers can also interact with The Globe on Facebook and Twitter .

Welcome to The Globe and Mail’s comment community. This is a space where subscribers can engage with each other and Globe staff.

We aim to create a safe and valuable space for discussion and debate. That means:

  • Treat others as you wish to be treated
  • Criticize ideas, not people
  • Stay on topic
  • Avoid the use of toxic and offensive language
  • Flag bad behaviour

Comments that violate our community guidelines will be removed.

Read our community guidelines here

Discussion loading ...

Cannabis pro newsletter