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Using a Radiator Cap Pressure Chart
Each radiator cap has a specific amount of pressure that it will hold. The radiator cap pressure rating system shows a range of pressures that the individual cap has been tested for. Even with a cap that is properly rated, it may be necessary to do a physical radiator cap pressure check to determine the maximum pressure that the cap will hold. For the best chance of using the proper radiator cap and parts, always check your vehicle manual and resources from the manufacture to determine what type of radiator cap should be used with your vehicle. Select your caps and other parts accordingly.