What is this?
In your car’s cooling system, coolant flows between the engine, radiator and heater core through a bunch of metal tubes and rubber hoses. The hoses are held in place by metal clamps.

These hoses, clamps and metal tubes need to be inspected for wear and degradation and replaced if they are in poor condition.

Should I do this service when it’s recommended?
Yes.

Why do I have to do this?
Rubber hoses degrade over time, and metal tubes can corrode. The metal clamps that hold the hoses in place can also loosen and/or corrode over time.

What happens if I don’t do this?
When rubber hoses degrade, they may develop cracks or holes. The metal clamps may loosen and fail to hold the hoses in place. In both cases, the coolant will leak out and your car will overheat. You might even melt your engine. At the very least, you’ll be stuck on the side of the road waiting for a tow truck.

Can I do this myself?
It depends on where you rank on the Car Talk do-it-yourself scale:

___ There are two kinds of screwdrivers?

___ I’ve successfully hung pictures around the house.

___ I’ve changed my own oil.

_X_ I’ve fixed things on my car that involve removing more than five bolts.

___ I’ve built a working nuclear reactor out of wood.

Note: You can do this service yourself, but it can be time consuming. Many coolant hoses can be difficult to reach. You’ll need to carefully drain the old coolant and refill the system with new coolant when you’ve replaced the hoses, and you also need to bleed any air that is trapped inside. Finally, remember to properly dispose of the old, toxic coolant by taking it to a local garage or to your town’s hazardous waste disposal center.

Is there any maintenance required between intervals?
Whenever you have the hood of your car up, take a moment to inspect the condition of the coolant hoses you can see, and wiggle or gently tug on the hoses near the clamps to make sure the clamps are still securely in place.

Car Talk Tip: If you do this service yourself, we recommend that you buy the hoses directly from your dealer. That way, you’ll be sure to have hoses that are shaped precisely like the old ones, and they will stay out of the way of other engine parts.