What Is the Difference Between the Upper and Lower Radiator Hose?

Your radiator is an essential part of your automobile. It does more than just hold the bulk of the car’s coolant, though. It’s actually responsible for removing excess heat from the coolant before it is sent back to the engine once more to start the process over again.

How a radiator works

Your radiator is made of both metal and plastic. Metal fins allow the heat absorbed by the coolant to radiate outward, where it is wicked away by moving air. Air flows over the radiator from two sources – the cooling fan (or fans) blow air over the radiator when it reaches a certain temperature. Air also flows over the radiator when you’re traveling down the road.

Coolant is transported into and out of the radiator by hoses. There’s an upper and lower radiator hose. While they both transport coolant, they’re very different. If you were to place them side by side, you’d find that they were different lengths and different shapes. They also do different jobs. The upper radiator hose is where the hot coolant enters the radiator from the engine. It cycles through the radiator, cooling as it goes. When it reaches the bottom, it moves out of the radiator through the lower hose and back into the engine to start the cycle once more.

The upper and lower radiator hoses on your engine are not interchangeable. What’s more, at least one of the two is probably a molded hose, rather than just a length of standard rubber hose. Molded hoses are specially designed for specific applications and are not interchangeable with other hoses, even other molded hoses on different vehicles.


The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

Related articles

How Long Does a Flexible Clutch Hose Last?
Within Within your vehicle's hydraulic clutch system is a flexible clutch hose. The purpose of this hose is to send fluid to your clutch, and it also works with your clutch salve cylinder. It is called a flexible hose because...
Symptoms of a Bad or Failing Flexible Clutch Hose
Common signs include difficulty shifting, low clutch fluid, and feeling no resistance at the clutch pedal.
How to Replace a Vacuum Hose
A vacuum hose is failing if the Check Engine Light comes on, the engine does not run smoothly, or the engine loses power and does not start.

Related questions

My radiator blew and overheated my van
You may have damaged the engine from continuing to drive it with it overheating. Specifically, you may have warped cylinder heads, cracked the cylinder heads, or pistons seizing in the cylinders causing a slower acting engine. The engine might start...
The CHECK FUEL FILL INLET message came on while I was driving down the highway and had not fueled in several days.
Try removing the gas cap and putting it back on. While the gas cap is off, check the seal on the cap and see if there is any cracks or damage to the seal. If the seal is good and...
What would cause coolant to be splashed on the engine and you hear a air sound while the car is running?
Hello, thank you for writing in. The first component that comes to mind is the water pump. It is one of the most common places to develop a leak. It may also spray out of that area, or drip down...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (855) 347-2779 · hi@yourmechanic.com