A car radiator is a mechanical component needed on a car that houses engine coolant. As engines run, they naturally build up a great amount of heat, and this heat would damage the engine if it were not cooled.
What engine coolant does is circulate through special passages on an engine, absorbing heat as it goes through. This heated coolant is then transferred to the radiator, where it is re-cooled to begin the circulation process again.
Every vehicle needs a radiator to survive because, without one, there is no way to re-cool the coolant. This would lead to engine overheating, which could lead to several problems, most of them severe.
An engine that has severely overheated is not going to run very well, especially if it is not attended to immediately.
A radiator is what keeps a vehicle from overheating, and as the tool that accomplishes this, it is a very necessary part of any vehicle. If you feel that your car radiator is in need of repair, then you should get it checked out before something goes wrong.
Being stranded due to overheating is a pretty common cause of breaking down, but this can be avoided, especially in older vehicles, by simply paying attention to the condition of your radiator. You can usually be very proactive against problems it may have just by checking for leaks, keeping it filled up, and by keeping antifreeze in it instead of water.
If you need to get a new radiator, consider taking the vehicle to the dealer or a professional mechanic. Not all mechanics will do radiator work, though most dealerships should be able to help you out. You can also get your radiator repaired. This can save you money, but it might require a bit of extra run-around time.
If you would like to find out more about the engine oil coolers as a different style of automotive cooling system, read this post.