now summer has come my car has been overheating going up a grade. It has always driven on this grade and stayed below the normal running temp. Where should i start?

 

In a word - thermostat.

Graham

 

I agree, definitely start with the thermostat.

If that does not solve the problem, the water pump vanes could be worn, or the radiator can be clogged (internally due to corrsion or mineral buildup, or externally due to dirt clogging the fins).

In any event, take care of this promptly. The coolant gauge on your car sits dead center until an overheating event actually occurs. Aluminum engines are not very tolerant of overheating.