Man - You're about 10 years late for any warranty work! A dealer or the Toyota 800# can tell you if and when the SSCV06 DEC 97 head gasket recall was done (if its a V6). I suspect there was a time/mileage limit on having it done that probably expired since its now 13 years old. If you know where the vehicle was serviced they may be able to provide additional maintenance records.