The 2005 5.9 diesel is a Cummings engine that can be found in the 2005 Dodge Ram model trucks. The accessories on the front of the engine are controlled by a single serpentine belt. The serpentine belt is tensioned to the accessories by a spring loaded belt tensioner device. This device keeps the proper amount of tension on the belt as it travels around each accessory pulley. Once the spring inside of the tensioner becomes weak or breaks, it cannot properly tension the belt and will need to be replaced.
Open the hood on the 2005 Dodge Ram and prop it open with the rod attachment.
Inspect the top left portion of the radiator cover for the serpentine belt routing diagram. This diagram shows exactly how the belt is routed around each accessory pulley.
Inspect the front of the engine and locate the spring loaded belt tensioner. The tensioner has a roller pulley on one end and a square hole at the top of the tensioner arm on the other end. Use this square hole to rotate the tensioner device.
Insert the head of the breaker bar into the square hole of the tensioner arm. Turn the tensioner device counter- clockwise. Once the tension is off of the belt, slide it out from under the roller pulley that is attached to the bottom of the tensioner. Release the tensioner and remove the breaker bar.
Locate the bolt head in the center of the tensioner arm. Loosen and remove this bolt head with the ratchet and a metric socket. Then, pull the bolt out of the hole and the tensioner will come straight off of the front of the engine block. Pull the tensioner off and match it to the new tensioner to make sure the tensioners are the same.
Position the new tensioner up to the engine block and screw the bolt back through the center of the tensioner arm. Tighten the bolt with the ratchet and socket until the bolt is very tight.
Turn the tensioner from the square hole with the breaker bar again. Slide the belt around the new roller pulley that is attached to the new tensioner. Remove the breaker bar and inspect the belt to make sure it is still seated within all of the accessory pulleys.
Crank the engine and inspect the new tensioner as the belt is traveling under it. The new tensioner should move up and down with the movement of the belt as the engine is running. Then, shut the engine off and close the hood.
