I have changed my waterpump on 97 f250, no leaks,and the rest of the cooling sys is new. Now my temp. guage is all over and moves close to red when i travel past 60mph, when I slow down or stop at red

SOURCE: Temp gauge fluctuation on 95 explorer

it is possible it might have a cracked or blown gasket head! simple trick check the oil to see if its milky colored if it is then its your head or head gasket if not let me know thanks josh........

SOURCE: Engine Temperature Guage on Dashboard indicates overheating

Hi and welcome to FixYa,

Offhand, your described condition indicates a sticking thermostat, that is there is considerable delay before the thermostat opens. It is also possible that there is some restriction wherein the thermostat is not opening completely when the triggering temperature has been reached. As a test and to confirm, you could try temporarily removing the thermostat and operate the engine without one; observe temperature. The side effect of this test is that it would take some time to warm-up the engine, but operationally should not cause anything untoward. Of course, care has to be exercised that the gasket would still be intact.

Good luck and thank you for using FixYa.

SOURCE: Cressida still pegs temp guage????????

1st do you loose water from the header tank or water dripping anywhere under car when stopped yes or no if yes to loss of water from h/tank then the problem is you have a Head Gasket blowing compression into the water jacket next to the cylinder,and its only small now but will get worse very soon, so get the Head removed and cracked tested and Head surface ground . Ron

SOURCE: 97 Cougar....Radiator not leaking....water pump

If your not low, and your not overheating, chances are that the level sensor is either dirty, or faulty. It's located in the coolant resevoir.