<!-- from fixya rte -->How to Change Antifreeze? - 2008 GMC Yukon

Bubbling means that it was above the boiling point. This is an indication that the antifreeze coolant mixture might be wrong. You should check that first to see if it is 50/50 water (distilled) and antifreeze. If it is not, you should check / change the thermostat. Make sure it is ok and the proper temperature. Check the radiator to see if it is obstructed INSIDE. Check the water pump to make sure the pump impellor is ok. Check the cap on the radiator to make sure it is working ok. (they are rated by pressure) then change the antifreeze coolant. What damage is there in over heating? The engine can blow out a head gasket due to unequal expansion of the metals.

You won't have to change your antifreeze unless a water pump or a coolant hose breaks.Antifreeze doesn't break down like the old green kind did.

Depending on where you drive and what temperatures the car is driven in will determine the concentration of antifreeze to water. As a general rule premix, which is 50/50, is fine for most application. Different concentrations will change the freezing and boiling points of the antifreeze mixture, as well as, change the ability of the mixture giving off heat. A typical 50/50 mixture has a freezing point of about -35*F and boiling point of about 265*F.

Hello,

For "ordinary" antifreeze, the vehicle manufacturers generally recommend coolant changes every two to three years or 30,000 miles. Others say it's not a bad idea to change the coolant every year for maximum corrosion protection -- especially in vehicles that have aluminum heads, blocks or radiators. But such recommendations may soon be obsolete. Several antifreeze suppliers have just recently introduced "long life" antifreeze formulations that claim to provide protection for four years or 50,000 miles.

General Motors just introduced a new five year, 100,000 mile antifreeze in its 1996 cars and light trucks. The new coolant is called "Dex-Cool" and is dyed orange to distinguish it from ordinary antifreeze (which is green).

The life of the antifreeze depends on it's ability to inhibit corrosion. Silicates, phosphates and/or borates are used as corrosion inhibitors to keep the solution alkaline. As long as the antifreeze remains so, corrosion is held in check and there's no need to change the coolant. But as the corrosion inhibiting chemicals are used up over time, electrolytic corrosion starts to eat away at the metal inside the engine and radiator. Aluminum is especially vulnerable to corrosion and can turn to Swiss cheese rather quickly when conditions are right. Solder bloom can also form in copper\brass radiators causing leaks and restrictions. So changing the coolant periodically as preventative maintenance is a good way to prevent costly repairs.


The basic idea is to change the coolant before the corrosion inhibitors reach dangerously low levels. Following the OEM change recommendations is usually good enough to keep corrosion in check, but it may not always be the case. That's why more frequent changes may be recommended to minimize the risk of corrosion in bimetal engines and aluminum radiators.


One way to find out if it's time to change the antifreeze is to test it. Several suppliers make special antifreeze test strips that react to the pH (alkalinity) of the coolant and change color. If the test strip indicates a marginal or bad condition, the coolant should be changed.

Regardless of the type of antifreeze you use, it should be disposed of properly. In many areas, it is okay to flush used coolant down the toilet (sanitary sewer) as long as the amount does not exceed a few gallons. But it should not be poured down a floor drain or into a storm sewer.
Both types of antifreeze are biodegradable but take some time to break down. Dumping used antifreeze into a storm sewer, ditch, creek or on the ground can contaminate ground water and kill plants and fish. What's more, used antifreeze picks up lead from solder in copper/brass radiators. Lead is a toxic heavy metal that can also cause pollution problems of its own.
Some areas prohibit ANY dumping of used coolant (sanitary or storm sewers). They also may not accept used antifreeze in a sealed container for landfill collection because eventually the container will leak its contents into the ground causing possible ground water contamination.
So how do you get rid of the stuff? You can take it to a local collection center that accepts used antifreeze for disposal or recycling, you can pay to have it disposed of as a hazardous waste (yeah, right) -- or you can take your vehicle to a garage or service facility that has a coolant recycling machine. The latter is the best choice because it eliminates the disposal problem altogether.
Coolant recycling machines work their magic by a variety of means. Some use filtration while others use a distillation process to remove the harmful contaminants from the old antifreeze. Corrosion inhibiting chemicals are then added to restore the coolant's corrosion protection. The auto makers have all approved coolant recycling as an effective means of eliminating coolant disposal problems, and each publishes a list of machines that meet their specifications. Recycled coolant must meet minimum standards of purity before it can be reused.


Reverse flushing is the best way to change the coolant because draining alone can leave as much as 30 to 50% of the old coolant in the engine block. Reverse flushing also helps dislodge deposits and scale which can interfere with good heat transfer.
The concentration of antifreeze in the coolant also needs to be checked prior to the onset of cold weather. A 50/50 mixture of antifreeze and water is recommended and will protect against freezing down to -34 degrees F and boilover protection to 263 degrees F.
For maximum protection, up to a 70% mixture of antifreeze can be used for freezing protection to -84 degrees F.

CAUTION: Do not use more than 70% antifreeze, and never run straight water in the cooling system because it offers no corrosion, freezing or boilover protection.

Take care and good luck

50% water 50% coolant. There will be a chart on the side of the Anti Freeze bottle. By the correct antifreeze GREEN Ethylene Glycol. NOT some fits all universal fluid.

Locate the antifreeze tank, If it's empty, just fill it with half water and half antifreeze but it's much easier to use 50/50 Antifreeze cause it's already premixed for you by the manufacturer all you have to do is fill it up to the maximum line.

At the bottom of the radiator there is a plastic knob this is the petcock drain plug it can be hard to see and turn so you may need to jack up the front of the car a little to crawl under the front and look at the bottom of the radiator but if you can reach it from the top and turn it with a pair of pliers do so that way this will allow you to drain the radiator, remove the radiator cap if it has one to allow air to pass through radiator, if it has no radiator cap remove the cap on the radiator expansion reserve tank, after all antifreeze is drained turn petcock drain plug back in till tight then refill raidiator with 50% water 50% anti freeze mixture, start car and top off antifreeze run the car or drive for ten minutes then top off antifreeze.

Best way to change the antifreeze is to open the petcock at the bottom of the radiator to drain the antifreeze/coolant. Once completely drained close the petcock and refill. Only other way would be to get a flush kit which involves cutting a heater hose, inserting a T and running a garden hose through the system with the radiator open at the bottom through the petcock while the motor is running.
Hope this answers your question. Good luck!
Greg

THE RADIATOR PLUG? IF SO THEY MAKE A SPECIAL SOCKET, ASK FOR A RADIATOR PETCOCK SOCKET. THEY ARE CHEAP, $2-$3

below radioator or side low should b plastic plug which u can unscrew & emty the fluid