You absolutely must consult a repair manual specific to your 2000 Ford Expedition's engine. This manual will show you the routing of the belt around the various pulleys *with* and *without* the AC compressor. It will also give you the correct belt size for the bypass configuration.
Attempting to guess the belt size is risky and could lead to:
* Incorrect belt tension: Too tight and you could damage bearings; too loose and the belt will slip.
* Belt slippage: The bypass might not have the correct length for proper engagement on the pulleys.
* Component damage: Improper routing can damage pulleys or other accessories.
Finding the correct belt size:
1. Locate your owner's manual: This might list belt sizes or refer you to a recommended parts source.
2. Use a vehicle-specific repair manual: These are readily available online and in auto parts stores.
3. Visit an auto parts store: Take your vehicle's information with you, so they can look up the correct belt size. They might even have a belt cross-reference guide.
Using the wrong belt size could cause serious damage, so take the time to find the correct information before attempting this repair.