Alternator/Fan Belt

If you don't have a belt to start with just use a piece of string. Just adjust the alt. to the middle of its adjustment slot and run the string then measure it. As stated buy a few around that size. If the guy at the counter can't figure out how to tell the the size it's usually the last 3 numbers. Say a 15341 would be 34.1 inches long with 15 being the standard width designation.