2001 Ford E-Series Van Transmission Service

I scheduled a routine maintenance service to have my transmission fluid replaced on my Ford Econoline 250 van. This model van comes with a transmission filter. What I would like to know is if the filter needs replacement as well? My mechanic says he usually just changes the fluid. I don't drive under any severe conditions just normal commuting type driving but if it needs changing I would want him to do it. Any help would be appreciated. Thanks.
Joe