4.6L & 5.4L V-8 Belt Tensioner Replacement

How to Replace the Belt Tensioner on a 4.6L or 5.4L F-150

If you've stumbled across this page, there's a fair change that you've managed to strip the 1/2 drive inlet on the belt tensioner. Fear not, this is extremely common as the tensioner is produced from relatively soft cast aluminum. If you're left with no way to get the serpentine belt off, simply cut it and install a new one once the tensioner has been replaced. For future reference, a serpentine belt removal tool seems to work much more effectively than a 1/2 inch drive breaker bar or ratchet.

Applicable Model Years: 1997 - 2010 4.6L & 5.4L equipped Ford F-150
1999 - 2010 5.4L Belt Tensioner: Motorcraft BT61
1997 - 1998 5.4L Belt Tensioner: Motorcraft BT62
1997 - 2001 4.6L Belt Tensioner: Motorcraft BT62
2002 - 2004 4.6L Windsor Belt Tensioner: Motorcraft BT62
2002 - 2004 4.6L Romeo Belt Tensioner: Motorcraft BT61
2005 - 2010 4.6L Belt Tensioner: Motorcraft BT61
Note - All P/N for engines with AC


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Belt tensioner location

Note - procedures based on 1997 to 2003 model year engine. Some details may differ for 2004 to 2010 model years.

• The belt tensioner is located towards the passenger side of the engine just above the AC compressor.

• Remove the belt from the engine. If you're replacing the tensioner because it is stripped, you may remove the belt by cutting it off (cautiously).

Belt tensioner removal

• Remove the (3) bolts that secure the belt tensioner to the engine block with a 10 mm socket.

Belt tensioner closeup removed from engine

• Install the new tensioner in reverse order. Use a liberal amount of anti-size on the bolt threads. Do not over-torque the bolts, the engine block is aluminum and easy to strip.

Serpentine belt reinstallation

• A common problem with the tensioner is that, even though it accepts any 1/2" square drive, is that some people will use a breaker bar or ratchet with a long extension. The spring loaded detent ball in these tools makes it difficult to fully insert the male square drive into the tensioner. Once pressure is applied, the square drive slips due to poor fitment, shredding the soft aluminum tensioner.

A belt tensioner tool, which is designed specifically for these applications, is inexpensive, more convenient, and more effective for these procedures.

• Reinstall the belt, rotating the tensioner tool clockwise to loosen the tensioner and releasing counter-clockwise to allow it to secure the belt. Follow the belt routing procedures posted for your specific engine on the underhood diagram.