Get to be OCD about Oil+Filter changes, considering the notorious TimingTensioner\Guides.
In addition to the ThermoStat Housing & Shocks that Ed mentioned above,
watch for coolant leaks\cracks on the
~ Plastic Tanked Radiator
~ Plastic HeaterControlValve
~ Plastic HoseTee for the PCVCoolantLoop
If not already done, after 19yrs it's time to replace\service coolant system items
~ Hoses+Clamps
~ Pump+Fan+FanClutch+SerpentineBelt
~ HeaterCore+Radiator Flush Then Fresh50/50, BackWash Fins Thru Fan With WaterHose
Replace all Fluids+Filters: Air, Fuel, Tranny, TransferCase, Difs, Brakes, Steering...
Replace PCVValve.
Sight+Sound Inspect All VacuumHoses.
Clean MAF, ThrottleBody, IACValve, EGRValve+Tube.
Inspect\Replace SuspensionBushings+Links
Inspect\Replace BrakePads+Rotors+Drums.
Hope this helps.