MANY TYPES OF LUBRICANTS ARE USED IN A VEHICLE. Engine oil and transmission fluid, on a volume basis, provide a major portion of the lubricants in a typical car or truck, and a great number of standard tests are associated with these fluids. Greases provide a variety of highly specialized functions and are found in many locations within a vehicle (for example, in door locks, gears for seat adjustments and windshield wipers, bearings, electrical contacts, and numerous other places).