Splash And Lubricate

In typical modern vehicles, oil pressurefed from the oil galleries to the main bearings enters holes in the main journals of the crankshaft. From these holes in the main journals, the oil moves through passageways inside the crankshaft to exit holes in the rod journals to lubricate the rod bearings and connecting rods. Some simpler designs relied on these rapidly moving parts to splash and lubricate the contacting surfaces between the piston rings and interior surfaces of the cylinders. However, in modern designs, there are also passageways through the rods which carry oil from the rod bearings to the rodpiston connections and lubricate the contacting surfaces between the piston rings and interior surfaces of the cylinders.
This oil film also serves as a seal between the piston rings and cylinder walls to separate the combustion chamber in the cylinder head from the crankcase. The oil then drips back down into the oil pan. To see these details on a crankshaft, see How Car Engines Work at HowStuffWorks or Types of Lubricating Systems at Integrated Publishing.Automatic transmission fluid is a separate fluid. It is typically colored red to distinguish it from the motor oil and other fluids in the vehicle. oil lubricates the joints and keeps them from overheating and gasoline burns in the engine generating exhaust and powering then car.