I have an overheating problem

I need help finding the problem on my 1996 Chevy Lumina. The car is always overheating. I use to lose a ton of coolant but i think it is staying in the reserviour since i changed the bypass hose. But my car is still overheating when i first get it on the highway, then after a drive a little ways it will overheat and i will slow down, stop, or turn the car off and it cools down. I go through that process about 4 or 5 times then the thermostat begins to register in the middle and it will continue to fluctuate between the center and hot. But it doesnt get all the way to the red. Can someone please help me out with this.

you might need a new thermostat

I agree with Topgun, better change it before it goes completely and leaves you stranded somewhere.

After you change the thermostat, make sure there is no air lock in the cooling system, remove all air pockets. Make sure your radiator fan kicks in at around 108 C.

If you haven't done so yet, have a cooling system pressure test done, just to ensure there are no more leaks. I would also look in to replacing the T-stat. Replacing the radiator cap would probably be a good idea as well. Also make sure the fans are kicking in when they are suppose to.

I have a similar problem......and a silly question; where is the thermosat located. I have a 95 Lumina, I just got a new thermostat but I can't see exactly where it goes. I see one hose that comes off the radiator that is big enough for the thermostat to fit in. Is it at the top of the hose where it enters the block, or at the bottom where it enters the radiator? Or am I in the wrong area?

I have a similar problem......and a silly question; where is the thermosat located. I have a 95 Lumina, I just got a new thermostat but I can't see exactly where it goes. I see one hose that comes off the radiator that is big enough for the thermostat to fit in. Is it at the top of the hose where it enters the block, or at the bottom where it enters the radiator? Or am I in the wrong area?

3.1 engines? under the throttle body on the end of the intake manifold

if you follow the top radiator hose you will find on the engine not the radiator there should be two bolts that go into the engine holding the piece that the hose is clamped to that is the easiest way to find the thermostat.

i got a simular problem with the addition to the above that my fans never kick in....I think it may be my head

My car started to overheat and then it just ened up dying on us the heater went out to and i think it could be the thermostat but im not to sure and i aslo have no idea where the thermostat is located so if someone could please walk me through this step by step that would really help out.

I would check all your hoses, make sure the radiator doesnt have leak somewhere, after running it for awhile turn the engine off and listen to see if you hear a hissing sound coming from your radiator, a temporary short term fix would be to use the additive that blocks up the holes.

Thermostat would definitely be an easier and cheap fix than replacing the whole radiator. Make sure you have equal parts coolant and water in your radiator as well.

Make sure that the water pump is creating good flow in the system.