What is the difference between orange and green antifreeze?

I have a 1998 Chevy s10 pickup and i noticed the antifreeze was low so we put regular green antifreeze in and when we opened the radiator cap the antifreeze in there was orange. I know that orange is used in gm vehicles but what is the difference and was it bad that i mixed the green coolant with the orange.

What is the difference between orange and green antifreeze?
after talking to a master mechanic for gm he says to never mix green and orange anti freeze as they are entirely 2 different chemical compositions,plus once mixed and heat added by driving a chemical reaction takes place,and the antifreeze turns to a jello like substance,no joke. evacuate the antifreeze system promptly and flush prior to replacing with fresh uncontaminated antifreeze,or blow the engine
Reply:I don't think it makes a difference, but the orange color might also be an indication of rust... I would check and make sure the mixture in your radiator is 50/50, they sell a silly little tool for doing just that, so long it's 50/50 then you should be ok.





You should be able to get an antifreeze mix tester at most any auto parts store, it has a small rubber hose and a clear plastic part with a gauge and a primer bulb, cost is like $10'ish or so.
Reply:The two types should not be mixed.





Most of the antifreeze products on the market currently are ethylene glycol base material with additives to prevent corrosion, lubricate seals and water pumps and aid in heat transfer to the coolant from the metal of the engine. Antifreeze should be mixed with distilled water (tap water contains high amounts of minerals such as calcium and iron that can precipitate and coat internal parts) at the ratio of one part antifreeze to one part water. This gives freeze protection down to minus 34 degrees and boil-over protection up to +265 degrees. Never use pure antifreeze in a cooling system without using at least 30 percent water in the mixture. Most antifreeze products sold for the past several years have been the traditional "green" coolant. This type is good for two to three years and up to 30,000 miles. The green antifreeze contains silicates, phosphates and / or borates as corrosion inhibitors to keep the solution alkaline. As long as the solution remains alkaline, corrosion is controlled and the system is protected. Over time, the corrosion inhibitors will be depleted and the corrosion protection is lost. It is for this reason that green antifreeze should be changed every two years or so. Aluminum is especially vulnerable to corrosion and many vehicles have heads, radiators and other aluminum components in the cooling system. If the coolant in an engine cooling system is changed before corrosion inhibitors reach dangerously low levels, corrosion damage is prevented.





An alternative to tradition green antifreeze is a product currently used by many engine manufacturers. "Orange" antifreeze is a long life or extended life type of antifreeze used to increase the useful life of engine coolant. It is ethylene glycol base as is the green antifreeze. The difference between the two colors is that orange antifreeze contains a different type of corrosion inhibitor that has a much longer service life than silicates, phosphates and borates. Orange antifreeze contains organic acids that protect engine parts from corrosion. Silicate (green) type antifreeze does not mix with orange type antifreeze. Never mix the two colors in a cooling system. The organic acids in orange types will cause precipitation of silicates in the green type and corrosion protection is greatly reduced. Orange type antifreezes are good for five years or 100,000/150,000 miles in newer vehicles (1996 and later). They can be used in many older vehicles (ask your vehicle dealer if it is safe to use orange antifreeze) if all of the green mixture is flushed from the system and is replaced with the orange mixture. Useful life is about four years or 60,000 miles in older cars.
Reply:Yeah, it's bad news to mix 'em. They are chemically different. You can flush out the orange stuff and replace it with green, that's what I do (been a mechanic for 25 years). Since you have mixed it, you will need to flush it out really well and put whichever you prefer back in.
Reply:Flush the system and then go back with the Dexcool. Also may sure you put a new good quality radiator cap on it. The green has silicates in it which is an abrasive and causes premature wear of components. The orange does not and last much longer as far as protection goes.
Reply:Your truck has factory filled Dex cool antifreeze. It's available every where you turn. The color is always orange. It's meant to last 150,000 between changes. I'd do it much sooner but that's just me.





The green type contain silicates which now is found may hasten bearing and seal life in the water pump. The old established Ethylene Glycol rust inhibitors are very limited after two years.
Reply:real bad! you better get your whole system flushed now, the orange and green don't mix and will plug your system up eventually, the orange is the enviromentally friendly anti freeze and as they say lifetime anti freeze and the green stuff should be changed every 2 yrs., you can use one or the other but not together, if you choose to use the green make sure your whole system is completely flushed, heater core and all of the orange stuff.
Reply:Orange is extended life coolant, it has a slightly different chemical composition.... if it wasn't much, it may not hurt, but I would consider flushing it out and replacing it all with the right coolant.

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