On Tue, 21 Sep 1999 rickaye@xxxx wrote: > has anone tried to use a engine treatement to the engine in there DMC. I have written on the subject of oil additives quite frequently. You might want to look in the archives. Anyway, the short answer is that an oil additive is just not going to do your engine any good. If you want to do your engine a good thing, use synthetic oil, or use regular oil and change it regularly. The basic reason for this is that the oil companies invest more money into R&D on their oil than the additive makers' whole company is worth. If there is some miracle ingredient that makes oil better, the oil makers would be using it already. Yet none of the reputable oil makers manufactures any additives - they don't even have any third party additives that they recommend. To compound things, oil is a very complex set of chemicals. Every oil is a little different, even though most of them are fairly similar, none are identical. The additive makers don't even know what sort of chemistry their product will be going in. Fuel treatments are typically in the same boat, except for fuel treatments that perform a specific task (stabilizer, injector cleaner, whatever - these are frequently, but not always, good at what they do).