Originally Posted by fuzz
If you have a leak you may want to look at the heater valve. I just had to replace it yesterday. My gauge spiked as well but the truck ran fine. Hope it helps.
I had the heater valve replaced last fall as it was leaking radiator fluid, but it's been good to go since then. The funny thing is that the needle in the temp gauge still worked fine during that time even with the leak. I think 05Edge is right in that it probably is just the gauge itself.
Since the truck is pretty beat-up and has 220,000 miles, is there any other way I would be able to tell it was overheating before it's too late? I've replaced just about every little small part on the Ranger that you can think of (EGR valve, heater valve, thermostat & sensor, etc.) and I don't really want to put that much more money into her.