There is no real solution to the Toyota engine oil sludge problem. It does not matter when you change your oil or what kind of oil you use (even synthetic), you cannot guarantee that you will not develop Toyota engine oil sludge. This is documented well by Toyota owner experiences. Some would like you to believe that Toyota owners aren't telling the truth; their accounts are accurate.
Please read the Toyota owner accounts at "Toyota Owners Unite for Resolution: Engine Oil Sludge" at http://www.petitiononline.com/TMC2003/petition.html.
Engine oil analyses are important in uncovering what is happening in these engines. The TBN is going below 2 with 5,000 mile oil changes. The TBN is below 3 even with 3,000 mile oil changes. The viscosity is reduced with as little as 3,000 miles on the oil. There is high silicon levels on each oil analysis.
The oil is designated "Abnormal Lubricant Condition." All this in a 1999 Toyota Sienna, currently with roughly 70,000 miles on it.
So what is really going on in these engines? More importantly, why are we being blamed? This is unacceptable.
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