I've been told not to change the Brand oil I use in my car. My mechanic says it will cause my engine to sludge up! Is their any truth to this statement?
Mark Sarlo my radio show co-host was the principal automotive engineer in charge of lubrication and combustion at SW Research in San Antonio, Texas. He and I have both looked very closely at such claims from others who have asked this very same question!
The truth is that not changing your oil is the MAIN reason for sludge formation! The other reason for sludge to build up is an engine running too cold! (Stuck open thermostat or wrong one)
This allows the engine to run "Too cool" and will never get hot enough to boil off moisture that has collected inside the engine. This will allow acids to form making SLUDGE in your engine, by overloading the additives that are in the oil to prevent this.
According to people that research oils, (Automotive engineers like Mark Sarlo) there is very little difference between brands in today's engine oils! What does matter is the API (American Petroleum Institute) and the SAE (Society of Automotive Engineers) approval symbol on the back of the oil bottle! It is a round "doughnut" with the letters API and SAE printed around the "doughnut". The words "Energy Conserving II” should be printed in the middle of the doughnut. You should see the letters SJ or SL printed in this symbol. These letters tell you that this oil is the most advanced formula of oil on the market, with ALL the mandated additives needed for today's cars.
So don't worry about the brands of oil you use. Just make sure they have the API, SAE approval! And change your oil regularly every 3 months or 3,000 miles. Taking care of your car is like putting money in the bank!
If you use synthetic oil you will be saving more money in the long run in fuel saving and engine wear and tear!
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