Check all the wiring and the Thermal Relay for the fan.
Problem?
multiples of 12 are 12,24,36,48,60,72,84,96,108,120,132,144,156,168,and180
just because the thermostat is new doesnt make it good your supposed to boil it in water to see if it opens and closes so it may be bad. if your car is low on oil it will overheat also or start the car and watch the radiator hose it it collapses then the hose is clogged and the water isn't flowing right which will cause it to overheat.
Probably it has either run out of coolant or the cooling fan is broken. Some large engine cars in really hot weather need a larger radiator fitted so it doesnt overheat....like driving a v8 around town in the summer in Spain for instance.
if the pump and thermostat have been replaced on a 2001 malibu and it overheats and the heat doesnt work now but the air does. do it need bleeding still , will air in the line still cause that problem...
so it doesnt overheat and d3stroy itself
well hmmmm tough 1st and farmost check make sure ur fans ar running to cool it 2nd u checked water pump but doesnt mean its good the coil inside could be shot change it let me know
only if it doesnt have fluid.
Make sure you have the correct thermostat in there, if it is set too high you will get that bouncing. The thermostat is set to open at a certain temperature and allow the coolant to exchange with what is in the radiator. Under normal conditions you will notice a rise and fall of the temp gage as the coolant reaches max temp then lowers after the exchange. An overly sensitive sensor or an aftermarket gage set up will exaggerate it. I would not worry too much since it is a good indication that your cooling system is working well, the coolant in the radiator certainly seems to be cooling down enough to cause a big swing in temp. Check on that thermostat though as it may be letting the coolant get too hot before releasing it.
Replace the thermostat.
could be a sticking thermostat.
Ford doesnt have a 5.7l. On a 5.8 it is behind the thermostat housing at the front edge of the lower intake.