How to Replace the Lower Radiator Hose on a 6.4 Diesel

Hose clamps fasten radiator hoses securely.

Radiator hoses provide a continuous circulation route for antifreeze to cool an engine. Cooled antifreeze travels from the bottom of the radiator to the engine. The upper hose carries hot coolant from the engine to the radiator top to be cooled. Radiator hoses deteriorate over time, causing cracks, breaks or an inner suction that causes collapsing hoses, rendering them useless. If the engine temperature is higher than normal, check the radiator hose with a visual inspection while the vehicle is running to notice abnormalities in a 6.4-liter diesel vehicle.

Things You'll Need

• Bucket
• Slotted screwdriver
• Lower radiator hose
• Ready-to-use antifreeze

Instructions

1. Park the diesel vehicle, raise the hood, and allow it to cool completely.

2. Open the radiator cap in a counterclockwise direction, and pull it straight off. Place a bucket under the radiator drain. Turn the petcock one-quarter turn to open the valve. The antifreeze will drain out of the radiator bottom and into the bucket. Allow all fluid to drain.

3. Insert a slotted screwdriver into the worm screw of the lower hose at the radiator. Turn the screwdriver counterclockwise to loosen the hose clamp. Slide the hose clamp down the hose away from the radiator, and pull the hose off. Repeat this procedure to remove the other end of the radiator hose.

4. Slide the hose clamps off each end of the old hose. Slide one hose clamp on the radiator end of the new hose about 4 inches from the end. Push the hose onto the radiator, slide the clamp over the end, and tighten the worm screw clockwise with a screwdriver. Attach the opposite end of the hose in the same manner.

5. Close the radiator petcock. Pour ready-to-use antifreeze in the radiator up to the bottom of the fill neck. Turn the vehicle on, and allow it to reach operating temperature. Squeeze the new radiator hose three or four times to purge the system of air bubbles. Add antifreeze to the radiator as the volume decreases to maintain a level at the fill neck bottom. Replace the radiator cap by pressing down and turning it clockwise to lock.

Tips & Warnings

• Do not reuse broken hose clamps.

• Check under the vehicle for antifreeze leaks at the hose ends while the car warms up, and tighten either connection if necessary.

• The antifreeze level in the radiator lowers when purging air from the system and when the thermostat opens and allows fluid into the engine block.

• Ready-to-use antifreeze is generally made up of 50 percent antifreeze and 50 percent distilled water. Check with your vehicle's owner's manual for manufacturer recommendations for coolant.

References

• RepairPal: Lower Radiator Hose Replacement