Consumers can find a vehicle's oil capacity in the owner's manual, on the manufacturer's website, on a specialty website, or by using the dipstick, states HowStuffWorks. Most vehicle manuals include the oil capacity with and without an oil filter.
For owners who do not possess a manual, most manufacturers show vehicle information and manuals online, according to HowStuffWorks. The vehicle's dipstick may also be used to find the engine oil capacity. To find the accurate oil capacity using a dipstick, the car engine must be cooled down and the dipstick should be clean from engine oil to provide a clear measurement. In addition, specialty websites offer oil capacity information based on a vehicle's model, make and year.