Over time and miles, your car might start to slow down. It might not accelerate as quickly as it once did; the engine may not run as smoothly as you remember, or the fuel economy may dip—but ...

Question:I own a 2003 Dodge Ram 2500, 5.7-liter V-8, and manual transmission, and the truck has 122,000 miles. Since new, I have used Mobil 1 fully synthetic oil and started using the Mobil 1 extended ...