One area of ??auto service that is often neglected is the vehicle's cooling system and this neglect can lead to catastrous consequences. There are a couple of reasons why the proper service and maintenance of the cooling system is so important. The first reason is the fact that cars today tend to be engineered "on the edge" with very little margin. This is especially true of the cooling system. In an effort to lighten the weight of a car, make them more energy efficient, and increase gas mileage, everything is smaller. Cooling systems today hold about half of the coolant that cars did many years ago. Modern radiators are also much smaller and light weight, so there is much less room for error. In the old days cars could have as much as half of the radiator plugged and still operate fine, but that's not the case today. In fact with some cars today, if they get as little as one quart low on coolant they can overheat. Everything has to be perfect for the system to operate correctly.
Another problem is the trend toward extended life coolants. All of the manufacturers today, in an effort to be more environmentally friendly, are installing extended life coolants that presumably do not need to be replaced as often. In fact some manufacturers do not recommend changing these coolants for up to 150,000 miles. This may work fine in the laboratory but it does not work so well in the real world. In normal operation, coolants tend to get acidic over time. When this happens and you have an acidic fluid in a cooling system it begins to set up a process called "electrolysis" that can do a lot of damage to your engine and other parts. One of the first components that can be damaged by this process is the heater cores. These units have the thinnest metal in a car. Repairing and or replacing a heater core can be very expensive, just ask one of your friends who has had to have this repair done. And if this component has been affected, chances are that other components are degraded as well. The main radiator in your vehicle can also be damaged because of an acidic coolant. Replacing a radiator in a car is also an expensive repair. Head gaskets are another area that can be adversely affected by this process. In the case of a head gasket, the electrolysis eats away at the aluminum surface of the cylinder head which ruins the sealing surface. Once this happens the gasket can not longer maintain the seal and it blows. If this happens there will be an expensive repair job in store. Even the cooling system hoses can be eaten away by the electrolysis problem. A hose may look perfectly fine from the outside, but the interior surface can be eroded, and if a hose blows it can also lead to a major repair.
While the manufacturers do not recommend changing the coolant for 150,000 miles, a good auto repair shop will have the ability to test the coolant for acidity level. If it is out of tolerance it can be flushed and changed before it becomes a problem. This service is much, much less expensive than repairing a blown head gasket. Make sure that your mechanic checks the acidity level of your coolant when you are having routine auto service or tune up performed on your vehicle. It just takes a minute to stick a test strip into the coolant and your mechanic can show you the results. This simple test could save you a lot of money.
Source by Pat Nicoll