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This is primarily intended for new first time owners of diesel engines. Diesel engines require a special API designation of motor oil that starts with the letter C as in compression ignition while different gas and gasoline engines take the designation starting with S as in spark ignition. The main difference is in the oils capability to control soot contamination by keeping it suspended and preventing it from thickening the oil into a heavy type syrup liquid. This is very important since the soot or carbon can form deposits on the pistons or become an abrasive component for the other bearing surfaces in the engine. The latest API designation for 2007 is CJ which can be found on the oil containers label. CJ is designed to reduce emissions when used in conjuction with the new Ultra Low Sulpher Diesel (ULSD) that is now being dispensed at your local fuel store. There are claims that the newer CJ oil may be lacking in some of its lubrication qualities since the sulpher content has been lowered just as in the ULSD fuel. The jury is still out on this and there have been may discussions on other diesel forums on this subject. Time will of course be the ultimate judge. Oil manufacturers of course have made claims that the newer CH oils have improved lubricating qualities but that will still need to be proven. I have been using either Pennsoil or Shell's Rotell T for the last fifteen years. I had the opportunity to talk about this with a friend (who locally owns a small trucking company) yesterday and we both agreed that an oil lubricating additive would be a good idea. He has been using Lucas heavy duty oil additive for over the last year with good results. This by no means is an attempt to promote any brand specific items as you may be getting excellent results with whatever oil you may already be running. I just used the examples of what I am most familiar with her in Pennsylvania. I also went to Shells Rotella website and found their FAQ section worth looking through. I saved the link which is:
Your brand of oil should have a similar website already set up.
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