How to Prevent Oil Sludge

Additives blended into your engine oil keep it from becoming acidic, prevent foaming and limit oxidation, which are all good things. Waiting too long to change your oil or overheating your engine can cause the additives to separate from the oil and turn into the dreaded oil sludge. When oil additives break down, they tend to solidify and turn into sludge. A buildup of oil sludge in your engine can lead to a number of problems, including significant damage to the rod and main bearings, crankshaft, and turbocharger. Sludge can even cause engine failure. What makes oil sludge even worse is that engine failures caused by sludge are not covered under your engine’s warranty.

But there are simple ways you can prevent oil sludge from forming. Read on for a list of tips.

First, follow the maintenance procedures in your owner’s manual. Change your oil as indicated in your owner’s manual or when you are notified by your Electronic Vehicle Information Center (EVIC). Always use approved engine oil (Mopar products or equivalent) with an API CJ-4 classification. API is the American Petroleum Institute, which sets the performance standards for engine oils. API CJ-4 oils are specially formulated for improved protection from thermal and oxidation breakdown. Developed for use in 2007 engines, they are backward compatible, so you can use them on any model-year Cummins Turbo Diesel engine with no change in oil drain intervals. In addition, make sure you change your oil filter as recommended with a Mopar or equivalent oil filter.

Second, avoid overheating. Overheating can cause your engine oil to oxidize, which can lead to the accumulation of oil sludge. Pay close attention to your gauges and repair any cooling-system issues that can lead to high operating temperatures. Some up-rate kits will cause a Cummins Turbo Diesel to run hotter than normal, which can increase the buildup of baked-on oil deposits that turn into oil sludge.

Third, if you’re using biodiesel, make sure it is a B5 blend (95 percent diesel and 5 percent biodiesel) and meets the American Society of Testing Materials (ASTM) standards. B20 fuel may be used only in approved fleets that meet certain requirements. Check with your local dealer for appropriate applications. Using non-approved biodiesel fuels can contribute to the formation of oil sludge.

Preventing oil sludge is simple. Following these steps will help ensure that your high-performance Cummins Turbo Diesel engine is never stalled by oil sludge.