Thanks for the all the useful information you gave over the phone about Auto-Rx and Shell Rotella-T for my rinse cycle. I have been a big fan of your product, it really does work! I own 2 vehicles both which are 2001 Chevy Prizms. My First Prizm has 66k miles. I been using Auto-Rx as a maintenance dose since I purchased it with 59k. It has really improved the overall engine performance and miles per gallon and the engine burns no oil. My second prizm had 98K and a replacement engine with 50k. I did 2 Auto-Rx treatments. Ive noticed better performance and fuel mileage on this vehicle also. This car went from burning a quart every 1K miles to a quart every 6K miles. I was really impressed. When I recently took off the valve cover to replace the gasket I noticed the valve train looks very clean also due to Auto-Rx. This car has128K and the engine now has about 70k and its and still running strong with Auto-Rx. Both vehicles get about 2 MPG more. I would recommend Auto-Rx to anyone who like to keep their car engine running like it was when it was new.