4.6L, 5.4L V-8 Serpentine Belt Replacement

How to Replace the Belt on a 4.6L and 5.4L Ford F-150

Nothing is more annoying than a squealing belt. Squealing upon start up is the first sign that the serpentine belt needs to be replaced. Eventually, the noise will stop going away after start up and will occur continuously. Replacing the belt is fairly straight forward, as all that's needed is a 1/2 inch breaker bar or belt removal tool. A belt removal tool is favorable because it seems to fit the 1/2" square drive on the belt tensioner more securely. The tensioner is made of soft aluminum and easy to strip, but it is also not difficult to replace.

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Serpentine belt tool installed

• Make sure you have the correct belt length and rib count. These vary depending on model year and engine configuration.

• Locate the belt tensioner. On our 4.6L, the belt tensioner assembly is located passenger side on the front of the engine (just below the alternator).

• Insert your 1/2 inch drive breaker bar or belt tensioner tool into the front of the tensioner. The tensioner is made of very soft cast aluminum, so ensure your tool is fully inserted before continuing.

Belt tensioner location

• Rotate the tensioner clockwise (towards driver side) to release tension on the belt. While maintaining pressure on the tensioner, slide the belt off of the top pulley. Release the tensioner and completely remove the old belt.

• Study the diagram found on the fan shroud or in your owner's manual and begin installing the new belt to those specifications. It is vital that the belt is installed per this diagram.

• You should have the belt installed with the exception of the top pulley (alternator, in our instance). Once again use your 1/2 inch drive tool to release the tensioner. This should allow you ample room to install the belt over the last pulley.

• With the belt completely installed, release the tensioner and double check your work. Make sure the belt is installed properly on all pulleys.