[George Bongert]

Not to start an argument here, but my 99 Bonneville is not equipped with a roller cam, and I have had no problems using synthetic oil, and I do not believe the camshaft in my engine is any harder, or had any different type of heat treatment than a camshaft from a 1960's era engine. In fact, the last 75,000 miles my car has been driven has been with synthetic oil. In fact If I had an engine of that vintage (1960 and on), I would not be afraid to use synthetic oil in it, even without the zinc additive, since synthetic oils have better lubricating qualities than regular engine oils. Case in point being, synthetic oils are not recommended for use until new or rebuilt engines are thoroughly broken in, since new piston rings do not break in properly due to the the excellent lubricating qualities of synthetic oils. Again, just my opinion, and not meant to offend or upset anyone in this forum.