Thermostat?

[lukecp]

I am having another thermostat problem with my truck. After i start it up and it runs for about 5 minutes, the temp guage will shoot way up, like to 240-250, then go back down to 215 or so, then back up to 240, and it will eventually go down to about 175, which is what it usually runs at. When it was running around 240, i popped the hood and felt the radiator hoses. The top hose was pressurized, but it was cold to the touch, about the same temp as the outside air. The bottom hose was getting pretty warm, and the heater hoses were pretty hot.

Is my thermostat the problem? I am running a Stant 160 degree stat in the truck. I have had bad luck with Stant themromstats....the last one i had which was rated at 195 degrees had the truck running at about 215 all the time. I put in the 160 degree stat, and it usually runs about 175 degrees. What is a good brand of thermostat to buy?