Looking for a direct fit, OEM quality replacement for your 7.3 Powerstroke 1999-2003 belt tensioner? Look no further than Alliant's AP63421 belt tensioner. This top-of-the-line tensioner is designed to provide superior performance and durability, and is backed by Alliant's outstanding reputation for quality craftsmanship. Don't trust your vehicle to anything less - choose Alliant for the best in belt tensioner technology.