Oil sludge residue help

Question

I have a 2007 Dodge Charger with 119k miles.. My engine randomly just seized and died while I was driving.. I towed the vehicle to dodge dealership for diagnostics, and they told me I've been poorly maintaining my oil because there is oil residue all over my oil filter, and it also clogged the screen which prevent passage for the oil which cause my engine to seized. But I have been routinely doing oil changes at this large franchise oil change company. I change my oil every 5k-8k and I do synthetic.. And before my engine seized my oil and oil filter was change about 3k miles prior. My question is can oil build up happen that fast within 3k of driving miles in my oil filter? Because my filter is full of gunk. Or is this poor workmanship?

And also, can oil build up happen if Oil changes were made routinely?

Answer 1

Oil sludging is caused by buildup of acids in the oil. This acid breaks down the oil. The acid is formed when water remains in the oil. The water reacts with contaminants in the oil. This combination of chemicals overwhelms the detergents in the oil. Water in the oil is normally removed through the PCV system. This works poorly when the engine is used for shorts trips because it does warm sufficiently to vaporize and get pulled into the intake. Water removal can also be impaired if the PCV system is compromised due to blocked hoses or a worn or incorrect PCV valve. Engine designs that include a PCV hose heater can significantly decrease incidence of sludge build up. Removal of these PCV heaters systems is common when intake systems are modified.

While oil quality is important it is not the determining factor in most sludge cases. Synthetic oil is no less prone to sludge that high quality blends, the protection additives matter more. Oil change interval must be significantly shortened for engines prone to sludge that are used in cool damp climates and used for short trips. Also PCV maintenance is very important in these cases.

Toyota and Chrysler each had several engines prone to sludge in the 1990’s. These cases were traced to a combination of lack of PCV heaters and short trip driving.

Answer 2

Poor maintenance would be the most obvious answer initially to such a failure. Just because the inside of the motor really does look baked. You can see how the oil has dried hard on the cranks main bearing caps etc. However this could also be as a result of the final seizure & extreme heat.

This certainly shouldn't happen though if the correct grade & weight of manufacturer's recommended oil and filter type have always been used, along with the correct oil level. There is always more of a risk involved when using spurious service parts. A cheapo oil filter can be the cause of this type of failure as I've seen them degrade in rare instances and as the internal paper construction material breaks down it can start to come apart. It shouldn't happen if services are regular enough though and decent quality parts are used.

If left too long between services the engine oils molecular structure can break down and become more and more contaminated as it degrades, oil sludge is the result, which can then cause flow issues & restrictions, and eventually as in your case lead to severe over-temperature conditions & seizure.

There is also the chance that perhaps something has failed internally lowering oil the pressure, bolts, clips and seals etc can break or degrade sometimes which could certainly cause an issue, maybe even something has gotten into the oil at some point, perhaps during service, and helped to block an oil way. Only a full strip down and investigation may help with that though.