Try checking the coolant level.

Here are a list of conditions that can cause an overheating condition;
A low coolant level, a coolant leak (through internal or external leaks), poor heat conductivity inside the engine because of accumulated deposits in the water jackets, a defective thermostat that doesn't open, poor airflow through the radiator, a slipping fan clutch, an inoperative electric cooling fan, a collapsed lower radiator hose, an eroded or loose water pump impeller, or even a defective radiator cap.

Loss of coolant because of a coolant leak is probably the most common cause of engine overheating. Possible leak points include hoses, the radiator, heater core, water pump, thermostat housing, head gasket, freeze plugs, automatic transmission oil cooler, cylinder head(s) and block.

Make a careful visual inspection of the entire cooling system, and then PRESSURE TEST the cooling system and radiator cap - with the engine cold. A pressure test will reveal internal leaks such as seepage past the head gasket as well as cracks in the head or block. A good system should hold 12 to 15 psi for 15 minutes or more with no loss in pressure. If it leaks pressure, there is an internal coolant leak (most likely a bad head gasket but possibly also a cracked cylinder or engine block).

It is important to pressure test the radiator cap, too, because a weak cap (or one with too low a pressure rating) will also cause the overheating.

The panel needs to be replaced. This is a common issue with GM trucks. The panel has to be programmed after installation which has to be done with a Tech II scan tool that the dealer uses.

Step 1: Open driver side door and leave open. Step 2: Lock and Unlock the drivers door using the power door lock switch etc.Read more : http://www.spobd2.com/

Probability here is greater than 75% that the wiper motor (which is an integrated module as well) is no good.

7.5 quarts of 5w30 and a new oil filter.

When your talking about performance, what exactly do you think this means? Go to the web and downlosd an owners manual if you need one otherwise always use what owner manual suggests as far as the octane rating. Be careful with ethenol

AutoMD does not.

Try http://www.autopartswarehouse.com/ JC WHitney, or US auto parts.net

Its headgasket problem

Check on-line for the many parts supply sources, such as; www.autopartswarehouse.com or www.rockauto.com for the replacement parts.