Just did my Impala SS,, I removed the lower rad hose and let it drain, The refilled with clean water,, drove it for a half an hour, let it cool and drained it again from the lower hose. I put the old fluid back in the new coolant jug and tapped the cap shut and put it out in the recycle bin,, trash folks took it with out an issue!!
Check your situation it may be different than mine but recycle will take oil and any other automotive fluids as long as they are secured (tapped shut) and labeled!!
Also,, I wore gloves also,, Dexcool is not people friendly!! or environment friendly!! make sure you flush skin with water if you get it on you and Protect your eyes!!

 

I just did my 2011 truck recently. Did like poster above. Drained it from
Lower hose. I also pulled the lower hose on my water pump to drain that. Reattached, filled with distilled water. Ran it to full temp, drained again the same way and refilled with dexcool/distilled water mix. I washed everything down afterwards in my engine bay. Definately remove the skid plate. I'd wear gloves and just wash your skin afterwards but don't get all crazy, it's not like it's flesh burning acid.

 

In addition to the gr8 advice you've already gotten....make sure you cleanup any spills. For some reason dogs and cats are drawn to engine coolant and it's very hazardous to them.

CityRado.

 

So by removing the bottom rad hose and thermostat the coolant in the block and radiator will drain out completely?

 

Don't need to remove the thermostat, although some people take the opportunity to replace it at that time just as a maintenance item. I also drained the water pump cuz it has probably a half gallon of coolant in it, but most people don't. Guess I just like to be thorough

 

Personally, I wouldn't mess with the water pump to do a coolant change. IMO, it would just invite potential problems. If it ain't broke, don't mess with it. Anyway, drain it once, refill with water and run it enough to get the thermostat to open and the water circulate, then drain it again and refill with coolant. But keep in mind, you likely won't be draining out all the coolant and will have to account for the fact that some of the water is still in the system. It is mostly water. So instead of putting a 50/50 mix in, you will want to add a portion of pure coolant to balance out the water still in the system. When you first drain the system, if you keep track of how much comes out, you will be able to figure out real close how much should still be in the system, provided it was full to start.

Also, I noticed someone mentioned to use distilled water to flush the system. I suppose that would be ideal, but for flushing purposes, I question the benefit of using distilled water. It isn't in there long enough to cause any problems with minerals (calcium) clodding the system. If you buy pure coolant and mix it 50/50 with water, then distilled would be beneficial. IMO.

 

Wont the thermostat close right back up when letting the engine cool down to remove the hoses? Would it be easier to just remove the thermostat and pour some distilled water into the top rad hose which will then come out from the thermostat location to flush out the block? Then put the bottom hose and the thermostat back in place and add 50/50 coolant into the top rad hose to fill the block up then connect the hose back then add coolant into the reservoir?

 

One thing I forgot,,, after you refill with clean water,, drive it and turn the heater on HOT at full blast to circulate thru the heater core.. Yeah as said,, you will not get 100% old stuff out, but you will get at least 95%!!

 

Sure, you don't have to drain the water pump or use distilled water, but doing so will help you get more of the old stuff out and when you flush with water and then drain, again you're not getting all the water out so using distilled helps make sure you're system stays as clean as possible. Again, I'm very thorough. Do it right and you'll sleep better.

 

Okay, here's what I'm getting out of all this:

So it seems I don't need to mess with the drain plugs on the block.

Looks like there are 2 ways people are suggesting:

1. Drain the old fluid from the lower hose, reconnect the hoses, fill system with water then drive around with the heater on to flush water thru the system. Come back, let the truck cool, drain the water out, then fill it back up with 50/50 dexcool/water and I'm done.

I'm voting for distilled water because if any of the non-distilled water stays in the system, it could cause a problem. I also have REALLY hard water, so I'm going with distilled.

2. Same as above, except remove the thermostat and drain the water pump. However, seems if I'm removing the thermostat, I don't need to drive it; I can just flush it with water from the hose (per the Haynes Manual).

Am I understanding everyone correctly?

I still need to find out about disposal locally. Maybe I can take it to a Chevy dealer?

 

AutoZone,Oriely's, and any or most auto parts store will take your fluids! I agree with you on the distilled water,, its cheap enough can't hurt.. Remember,, its not brain surgery,, your replacing the old fluid,, how in depth you wish to get is up to you!! You could even buy a "Flush Kit" and definitely get 100% of it!! My Impala only has 47K on it so for me the coolant looked ok,, I feel I got 85-90% replaced with fresh so I am happy!! If you find the drain blocks on the motor and you pull the thermostat and the lower hose,,, you will get close to 95% out.. That should be good!!

 

In SC the auto parts stores do not take coolant. Might be different in California. I'd call the stores, first.

 

For assurance, you could purchase an anti-freeze hydrometer; they don't cost much. It won't measure the actual concentration of water and coolant, but it will indicate if you have sufficient protection from either freezing or boiling.

If cost is not an issue and you want to do it yourself, then you may want to look into the pre-mixed fluids that are already 50/50. The water they use is compatible with your engine so you won't have to worry about using distilled water.

 

your lower rad hose should be below the thermostat hose..thus gravity will do its job. the only coolant left will be in the heater core...which can also be flushed (my 04 has never had its core flushed...doesnt really need it heater blows hotter than gang busters

also your coolant should be dex cool which isnt Ethyl-Glycol (the "bad" coolant that kills animals) PG or prop-glycol is 100% eco-friendly which i think spawned the specification as well as it being good for alum. radiators and preventing corrosion/long lasting life.

 

I'm in the process of doing this. I drained the coolant out. It was easier to use the hose that goes to the thermostat instead of the one that goes to the radiator. I filled it with hose water, drove it around for about 10 minutes and let it idle to get hot enough to get the hose from the thermostat to the radiator (bottom one) hot. Top hose was hot. I ran the heater the whole time.

1. The fans never went on; is that a problem?

2. I filled about half of a 5 gallon bucket with coolant. Probably spilled a gallon. Seems like there should be more.

3. I'm waiting for the truck to cool so I can drain the water. Should I drain and fill it with water once more to get more out?

4. I bought the pre-mixed Dexcool/Water mix. How critical is it to get the 50/50? What if it's 45/55 or something?

 

2009 Silverado 100k Coolant Flush
Read here
It will tell you exactly what you need to do, start to finish.

 

Excellent suggestions for changing out coolant for a newbie '11 Sierra 4.8L owner like me. I've done 2 drains so far with at least one more planned. I've taken off the engine side radiator hose both times and I've learned that some patience and planning does reduce mess. For starters I taped together a couple of long sheets of tin foil and molded that around the belts as best as I could to reduce coolant splashing on them. Then I took an extra minute or two letting coolant drain more slowly and controlled the fluid drain direction to the gap in the splash shields on the passenger side of the engine to avoid that initial big messy surge. I placed a catch pan right under that spot and used a washing machine pan to get other minor unavoidable drips the catch pan's too small to get. Once the coolant's been drained to a very slow drip the radiator hose is wiped down & reconnected. I used an oblong 4 gallon pail to mix 1 gallon each of coolant and distilled water and have a long neck plastic funnel that fits the reservoir fill hole perfectly so I can fill with no spillage. After filling I've been measuring both the drained and newly added coolant. In both cases I've only squeezed in roughly 6.5L (6.8 qts) initially and I'm estimating (based on 16.9 qt coolant capacity) that 2 fills gives ~70% new coolant. I know it's a bit overkill but I'll get 80% new coolant with a 3rd drain. The Dexcool jug says it's supposed to be good for up to 240K km so 80% new charge should hopefully keep things in good stead for a few years. Incidentally the coolant I got back after the 2nd flush looked way better than the old brownish stuff that was originally in there. I do wonder if the last owner did anything like a coolant drain in the past (the Sierra's got 250K km) so it's overdue I think. I did take the truck out for 1/2 hr minimum drives between flushes with the heater set to max. The engine temp (touch wood) has been steady at 100C.