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 ...

Diesel truck fans may have heard the legends surrounding the 12-valve Cummins. Found in trucks like Dodge Rams from 1989 to 1998, its fully mechanical fuel system and rugged injectors are celebrated ...