Howdy, '99 SR5, ~200k miles, alternator replaced ~3 years ago with new OEM, battery about the same age. Runs like a top, ScanGauge always hooked up to monitor volts and water temp, always in charging ~13.5v +/-.2 or so, always ~198*+/- a few*.
Parked it yesterday for ~3 hrs, it was ~40*...