ZTR tranaxle fluid change

Hi Everyone I am in Wester PA & store my BZE38" ZTR mower over the winter months & I am concerned that there could be a build up of condensation in the transaxle fluid & wondered if changing it on my own is advisable? I am pretty competent at most all vehicle repair & maint. but couldn't find any info on the proceedure. It is a 2003 model & has never been changed.