Mitsubishi Repair: montero overheating problem, mitsubishi montero sport, cylinder head gasket

Question
I have a 2000 Mitsubishi montero sport, ls, 3.0, automatic. My problem is that every time i go up hill, my temperature gauge also goes up almost to the point where it start to overheat.I changed my radiator and my thermostat thinking that was the problem, but when i tried to go up hill again,it's still doing it.i dont know what else causes this problem or what the problem is.pls help.

Answer
Marlon,
I've seen this problem happen when the water pump cannot maintain proper pressure.  Lack of pressure while driving uphill causes the coolant to move towards the firewall and away from the radiator; resulting in overheating.  Lack of pressure can be caused by a weak water pump, lack of engine coolant, or potentially a warped cylinder head gasket.  I would recommend having your mechanic do a compression test to see if your cylinders have the proper compression.  Continuous overheating, even briefly, can cause significant damage to the engine.  Have this looked at as soon as possible.
Good luck!