What you guys think???? Does fresh oil have enough extra chemical capacity to make it worth useing for a 5-15 minute solvent based flush? Is it worth it to drain out the old oil after say 6 months and add 4 fresh quarts and 1 quart of oil flush? The reason I ask is becasue I am going to use an Amsoil Engine Oil Flush. It is a simple solvent based product. The engine is clean and is being flushed as a preventive item. I could not afford Auto-Rx or a gallon of LC. The engine is 3 years old and has slightly less then 40,000 miles. The car has been run on M1 mostly but has seen some GIII and GII oils. In the past long before Auto-Rx or Lube Control I would simple add the flush to the exsisting crankcse oil. Now I am thinking that 4 fresh quarts of cheap dino oil might be able to hold more of what ever the flush disolves. Let the debate begin!!! P.S. When I was a young aprentice in Germany we used 5W20 Flushing Oil and did not add anything else. The most popular one was Motul 5W20 Flushing Oil. Boy how things change!