Have 2008 Mazda 3 Touring with about 53000. Dealer maintained since new with last service 10/13. The temp guage is going up to about 3/4 when I'm at highway speed and then drops back to regular 1/2 way spot when I get off highway. Checked fluid and appears to be right at max - it's really hard to see. Looks like things like temperature guage are covered under 60K warranty - should I be worried about driving on highway to dealer? Any thoughts or recommendations?

 

this is just me but i would go into the dealership and see what they can find out. i would also check over everything else,look for small leaks that kind of stuff

 

check if the thermostat is under warranty, it might be faulty due that is not fully opening, that if the fan is turning on with/ without ac on and there are no leaks