The coolant system also has a branch that goes into the passenger cabin called the heating coil. This is where the car’s environmental controls draw heat from. In some cases turning on the heat can help to cool the engine.
Traditional coolant has a life expectancy of 3 years or 36,000 miles because it is petroleum based and it starts to break down. Around 2005 a new coolant was developed based on a synthetic base to give it an extended life. Now coolant lasts up to 100,000 miles.
What Can Go Wrong
The material in the rubber hoses used in the coolant system can break down and fail without proper maintenance. This is mostly due to the coolant becoming corrosive and eating away at the rubber. Additionally, coolant that is not working as well as it should allows for much higher temperature ranges that cause the rubber to expand and contract more, advancing the breakdown process.
In newer vehicles, in order to reduce weight, a plastic tank is used for the radiator. Extreme temperatures can cause the plastic tank to crack and leak the coolant out of the system.
The water pump requires lubrication to work properly. Older coolant can lack the lubrication needed to keep the water pump working well and this may result in water pump failure.
Care and Maintenance
Most manufacturers highly recommend maintenance on the cooling system within the 60,000 to 70,000 mile window. During this time, the fluid can become corrosive and the lubricants become depleted. The combination can cause the parts of the cooling system to wear over time. On cars older than 2005, most manufacturers recommend maintenance every 36,000 miles to keep the system operating properly.
Proper care and maintenance includes getting the cooling system inspected and serviced every 3 years or 36,000 miles to prevent issues from arising. AAA reports that the number 4 reason for car breakdowns is a failure in a coolant system hose. Inspection and service can illuminate these issues before they cause a breakdown.