One problem related to engine belts and pulleys has been reported for the 2003 Subaru Legacy. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2003 Subaru Legacy based on all problems reported for the 2003 Legacy.
Vehicle had coolant flush in Dec 2007 (39,924 miles). Coolant leaked after this service. In Jan 2008 (40,912 miles) Subaru dealer put additive in coolant to seal leak and indicated manufacturer extended drivetrain warranty for this model. In Dec 08 coolant leaked. Head gasket replaced 6 weeks after warranty expired (46,457 miles). There was no extension to the drivetrain warranty despite being told such by service advisor (apparently that ended in 2002). Subaru did pay for all by $500 of work. Subaru also indicated they would not guarantee the drive train belt from failing and recommended replacement at my cost.