Internet chatter concerning engine oil sludge problems associated with Toyota Corollas has been circulating for years. Multiple site listings appear when one researches the key words "oil sludge and Toyota." Sites such as ripoffreport.com and corolland.com have documented cases of disgruntled Corolla owners who've had bad experiences with the oil sludge in the engines of their cars.
Synlube.com says that 3.3 million Toyota engines were affected by engine oil sludge. According to the website, out of the above said number, 7,000 of those engines experienced serious failure. Corolland.com says Toyota engines are prone to sludging, and cars that are only a couple years old are not immune. Reports logged on corolland.com tend to mirror this statement.
Engine oil sludge is the thickening and the breakdown of the engine oil as it deteriorates. Auto technician Norris Schleer wrote on his website that contaminants and moisture build up and the oil gels, which results in excess wear as friction increases. Oil circulation is compromised and engine seizure can result.
Since April 2002, Toyota's response to the oil sludge problem was instituted as customer satisfaction program for owners of 1997 to 2002 Toyota and Lexus vehicles equipped with the 2.2-liter four-cylinder and 3.0-liter V-6 engines. The satisfaction program, according to corolland.com, states that Toyota "is taking this action because a very small number of customers have reported engine damage from motor oil breakdown, also known as oil gelling or 'sludging,' a result of oil change intervals delayed beyond the factory-recommended schedule. While any make vehicle can suffer from this condition if the oil is not changed often enough, Toyota has initiated this program to ensure owner peace of mind."
One of ways to look for oil sludge is to remove the valve cover and examine the parts underneath. Photos on Norris Schleeter's website and synlube.com show an engine with an oily gel coating its parts. At this point the oil cannot prevent contaminants from harming the engine.
Signs of oil sludging are oil gelling on the internal parts, which are especially visible when the oil filler cap is removed. Fixes include engine flushes, more frequent oil change intervals (more often the recommended 5000 miles), use of synthetic oil and even engine replacement.
