A radiator hose is a flexible tube used to carry coolant between the radiator and other parts of your vehicle’s cooling system. There are many radiator hose sizes available in the market.
You must be aware of all standard radiator hose specifications. That is why we have written this guide. You will explore options for radiator hose diameter, wall thickness, angles and many more.
Radiator Hose Size Chart
To buy perfect radiator hoses for cars, trucks or other vehicles, you need to choose a size that matches radiator and engine connections. So if you are an auto parts distributor, wholesaler or B2B buyer, you can use the chart below to compare common radiator hose sizes.
These measurements will help you to select the right hose for your product range or bulk purchasing requirements.
| Inside Diameter (ID) | Outside Diameter (OD) | Wall Thickness | Working Pressure | Burst Pressure | Applications |
| 127 mm | 140 mm | 6.5 mm | 66.7 psi (4.6 bar) | 13.8 bar | Industrial equipment/trucks and marine engines |
| 115 mm | 128 mm | 6.5 mm | 73.9 psi (5.1 bar) | 15.3 bar | Heavy-duty industrial & commercial vehicle |
| 102 mm | 113 mm | 5.5 mm | 70.1 psi (4.8 bar) | 14.5 bar | Large agricultural or marine machinery |
| 90 mm | 101 mm | 5.5 mm | 79.7 psi (5.5 bar) | 16.5 bar | Trucks, buses & heavy equipment |
| 76 mm | 87 mm | 5.5 mm | 94.2 psi (6.5 bar) | 19.5 bar | Custom turbo/intercooler piping setups |
| 70 mm | 81 mm | 5.5 mm | 101.5 psi (7 bar) | 21 bar | Tractors and stationary generators |
| 66 mm | 77 mm | 5.5 mm | 101.5 psi (7 bar) | 21 bar | Commercial refrigeration or bus cooling systems |
| 61 mm | 70 mm | 4.5 mm | 95.7 psi (6.6 bar) | 19.8 bar | Construction equipment or auxiliary pump assemblies |
| 51 mm | 60 mm | 4.5 mm | 101.5 psi (7 bar) | 21 bar | Performance cars and light trucks |
| 48 mm | 57 mm | 4.5 mm | 101.5 psi (7 bar) | 21 bar | Classic cars or industrial engines |
| 45 mm | 54 mm | 4.5 mm | 101.5 psi (7 bar) | 21 bar | Off-highway vehicles or passenger cars |
| 40 mm | 49 mm | 4.5 mm | 101.5 psi (7 bar) | 21 bar | Light commercial vehicles |
| 38 mm | 47 mm | 4.5 mm | 102.5 psi (7 bar) | 28 bar | Medium duty trucks or buses |
| 35 mm | 44 mm | 4.5 mm | 102.5 psi (7 bar) | 28 bar | Passenger cars, trucks and engine cooling systems |
| 32 mm | 41 mm | 4.5 mm | 102.5 psi (7 bar) | 28 bar | Tractors and compact machinery |
| 30 mm | 39 mm | 4.5 mm | 102.5 psi (7 bar) | 28 bar | Small vehicle / motorcycle radiators |
| 28 mm | 37 mm | 4.5 mm | 102.5 psi (7 bar) | 28 bar | Small cars, motorcycles and auxiliary cooling lines |
| 25 mm | 34 mm | 4.5 mm | 102.5 psi (7 bar) | 28 bar | Small engines, motorcycles and sometimes for bypass lines |
Definition of Technical Terms
What is ID and OD of Radiator Hose?
Inside diameter is an open space inside the radiator tube where coolant flows. It basically tells you the width of the hose opening. In contrast, the outside diameter shows you how wide the radiator hose is from the outside.
You can use these specifications to select a hose that can perfectly fit radiator and motor connections. Suppose a connection has a 1-inch opening. Then you should look for a radiator hose with a matching 1 inch ID. However, OD will help you to check the hose wall thickness as well as choose the right clamp size.
Wall Thickness
It is the thickness of material between the inside and outside of the radiator pipe. You need to verify wall thickness if you are conscious about hose strength, flexibility and overall construction.
Because it has a direct effect on radiator tube heat resistance power and pressure handling. If we make it simple, a thicker hose wall can handle higher internal pressure plus offer better protection against outside damage.
Pressure Rating and Burst Pressure
Pressure rating is a safe range of pressure that a radiator hose can safely handle during normal use. You can see this value listed as working pressure in the above table.
Regarding burst pressure, it is the force hose can handle before it fails or bursts. Mostly, this value is much higher than the normal working pressure of a coolant tube.
Radiator Hose Angles / Bends
Engineers also design radiator hoses with various pre-formed bends and angles. The main goal is to make your job easy if you want to fit a pipe in a tight place.
You will face this situation in case your car engine parts are located very close to each other. To prevent sharp bends and kinks, you can consider these options.
45 Degree Radiator Hose
A 45-degree radiator hose elbow has a fixed bend of approximately 45°. This angle works well if the radiator and engine connection points do not line up directly. Manufacturers produce these hoses from materials such as EPDM rubber and reinforced silicone. You will find their inside diameter around 0.75 to 3 inches (19 to 76 mm).
Radiator Hose 90 Degree Bend
This radiator hose has a sharp right-angle turn. Due to this shape, you can use it to connect two points if the radiator & engine connections are at 90° to each other. In most cars, you will generally find top radiator hoses with two 90 degree bends. Because it gives the hose some flexibility as the engine moves or twists inside the engine bay.
135 Degree Radiator Hose
You will find this tube with a wider bend as compared to 90 egress hose. Due to this angle, you can make a 135-degree change in direction. This shape is perfect if the cooling system requires a wide turn around engine parts or other obstacles.
They are made of multi-layer silicone or reinforced rubber. These materials make them able to handle high temperatures and cooling system pressure.
180 Degree Radiator Hose
This tube has a U-shaped bend. It changes the hose direction by 180 degrees. This shape lets you route coolant back in the opposite direction.
You can use it if radiator and engine connections face the same general direction but need a U-turn. Further, it makes a U-turn in a tight space without sharply bending a straight hose.
What Size Radiator Hose Do I Need?
If you want to select the perfect radiator hose size, you need to start with measurement of the inside diameter of your old hose. As you can see in the above sections, radiator hoses are sized by their inner diameter.
Most passenger vehicles use upper and lower radiator hoses between 1.25 and 2 inches in diameter. But remember, the exact dimension depends on your vehicle’s model and engine.
How To Measure Radiator Hose Diameter?
To check the inside diameter (ID) of the radiator hose, you have to place your measuring tool across the hose opening (one inner edge to the other). You have two options for measurements. A caliper gives you the most accurate details. However, you can use a ruler or tape for a quick check. For a practical guide on how to find accurate radiator hose diameter, you can watch this video.
Tip: We also recommend that you confirm the hose length between its two ends. In case you want to replace a bent hose, you should check the bend angle and leg lengths too.
How To Find Radiator Hose Size Without Removal?
If you notice a hose has a size printed on its surface, you should always use that information first. You can also measure the outside diameter with a caliper. Then estimate the inside diameter by subtracting twice the wall thickness.
But if you cannot find the size marking, another option is to check the radiator or engine connection size where the hose attaches. The best approach is to compare the hose with the vehicle manufacturer’s specifications or the original hose part number.
Can You Stretch a Radiator Hose?
No, you should not stretch a radiator hose to make it longer. In fact, it can become risky if you try to force a radiator hose onto a connection that is too large. The reason is very simple, radiator hoses have a fixed size plus contain reinforcement layers for strength.
If you stretch the hose, these layers can get damaged. As a result, the hose can lose its proper shape and place extra stress on the material. So, there will be a high possibility of leakage or hose failure.
Customized Radiator Hose Dimensions For Retailers and Wholesalers
The sizes listed above cover standard radiator hose dimensions. But if you are a distributor or bulk supplier, you need hoses with different sizes, shapes or bends. In that scenario, you can choose custom hoses made to your required dimensions.
RONTEIX engineering team can make custom radiator hoses for different vehicle engines as well as industrial applications. We offer OEM & ODM services for business. You can request custom ID, wall thicknesses, lengths, shapes, bend angles and colors.
We can handle customization of a single sample plus large production order. You can also get custom-made rubber or silicone radiator hoses based on your required temperature or material. Contact us and share your 3D/simple hand sketch, OEM sample or basic requirements and we will start manufacturing process as soon as possible.
Conclusion
When you are talking to an automotive hose manufacturer, the first thing you need to confirm is their certifications & product standards. Then you can ask about the customization options, MOQ and production capacity. We advise you to request samples of hoses before placing a bulk order.
If you care for attention to detail, it is best to get company’s official specification sheet or catalog. Once you carefully check all these details, we are confident that you can choose right coolant hoses for your vehicle.
