My '98 K1500 5.7Vortec uses a 195 thermostat. I would not change it out for a different temp, because the whole system is designed with that operating temp. If you're wondering about it, I'd go to my Chevy dealer and buy a high quality 195 thermostat (if that's the factory temp for your engine) and stick it in. I would NEVER AGAIN buy an important component from Auto Zone, O'Reilly's, or any other discount outlet. NEVER. I paid for that lesson once, and that's enough for me.