I'm moving over from the C4 community I need some C6 answers
# 1 how do you back flush a C6.
# 2 can I use a Prestone back flush kit" I have 1 remaining from my C4"
# 3 must the cooling system be burped like you do on a C4?
# 4 Where can I acquire a Factory or after market C6 repair manual?
thanks boonie

 

#4 in the parts for sale section you can find shop manuals.

No clue on the antifreeze.

 

The burping is mostly done by filling up the coolant reservoir (not too high), warming up the car and watching it go down, then refilling. Can do that for one or more startups thereafter (watching coolant level in overflow tank to see if it's at proper height).

 

best tool I ever bought

 

The easiest way to change the fluid is to drain/refill w drinkable water/run the engine until the thermostat reopens then repeat until the drained fluid runs clear. This usually takes about 3 refills and ensures the coolant in the block is water. Then add straight Dexcool to make up half the system's capacity and top off with more water. This gets you right around 50% mix. Run the car for a while and let the cooling system get up to temp, let cool down and add water as necessary to bring the level back up after the air is purged. That will bring you in right at 50%. No need to try and use the backflush tools. I used to use one on my C4 but there is no need on the C5 and newer cars. Also make sure you do not use the Green Coolant like you did on your C4. That stuff is crap compared to Dexcool which will last for 5 years/150K miles instead of 2 years for the greenstuff. My 03 Tahoe is on its second 5 year flush and refill and two years after making the change the fluid still looks like the day I installed it two years ago. My 08 Malibu is on its 1st flush/refill and two years after it was flushed it looks great. The Corvette would be on its 1st flush/refill as well but it had its engine replaced 3 years ago so is out of sequence with the others.


Bill

 

I love how they use the words "drinkable water" in the manual. I guess they don't want us to use toilet water or green swamp water but everything else is ok.

 

These info are not entirely correct.

There are loads of info by using the search function.

This is a good read among many others:

https://www.corvetteforum.com/forums...+water+coolant

 

Interesting conversation. I buy the premix and forget about it. So I am paying extra just for water, but if you look at it, it really isn't much. Plus my mix is always 50/50.

Prestone GM pre-mixed dex-cool is recommended for use in all vehicles that require GM Dex-Cool coolant for topping off.

Rust and dirty coolant that circulates in cars cooling system can lead to a clogged radiator, resulting in overheating and engine damage, Prestone antifreeze contains inhibitors for extended performance and protection against rust and corrosion
Patented formula has a concentrated blend of premium long-lasting inhibitors for extended performance
Protects against temperature extremes and the ravages of rust and corrosion for 5 years or 150,000 miles

 

I'm with you. The BEST tool ever for filling cooling system to insure there are NO bubbles. Takes about one minute to fill cooling system. I use it on all my vehicles including my tractor.

 

I agree that this sounds nice, but since it is not possible to get all the coolant out of an engine block, how can you get the final mix up to 50/50 by adding 50/50 to the system? You will always end up with your 50/50 being added to some amount of water that is already in the system. The amount of water left in the block after flushing is significant too...it is many quarts.

 

I think their intent is that they don't want us to use distilled water, which is agressive and will attack metals in the system like radiator and block. Water that already has some minerals in it will not be as likely to try to pull minerals from the walls of the cooling system.

 

Good point! I just don't worry about it! I put a bottle of Water Wetter in every other year to help with corrosion (I know that dilutes my 50/50) and have never really had an issue with cooling system corrosion in any of my cars. I keep cars about 5 years. The Corvette is the exception.

 

X3 - I own one as well. Works like a champ!

 

Please provide link/links to solidify your ^^^ posting.

Or, is your above just what you think is true?

 

They could have just said tap water though instead of drinkable, which distilled certainly is not. I've been using tap water/coolant according to the manual in all my vehicles for 37 years and never had a single cooling system problem. Those are facts enough for me.

 

So...what happens to us if we drink distilled water?

 

It's just my opinion, that's all. I know that distilled water is aggressive from my knowledge of swimming pool and spa maintenance. Aggressive water is the enemy of pumps, heaters and other metal components. The same applies to aluminum engine blocks, water pump blades and radiators, except to an even greater degree because the higher temperatures accelerate these reactions. Some amount of dissolved minerals already in the water is a good thing...much better than the cooling system components providing them. The water is going to get them one way or the other.

And I agree with EVR, they could have made it simpler by just saying "tap water"

 

We need minerals and drinking water is a good natural source. There's no metal in our bodies for the water to pull minerals from, but distilled water is certainly not the natural drinking water of humans or animals.

 

The reason I bring this up is I think there is more at play here than just the use and debate of distilled or tap water. I think what is more important is the coolant in the system remain ph balanced so that electrolytic corrosion does not get started. I know in some places of the country there is a lot of dissolved minerals in tap water, I've seen it ruin shower heads, dishwashers, etc, so in no way shape or form would I add it to my cooling system. More importantly, the antifreeze used should be neutral ph balanced so it is neither acidic or basic. The only brand of antifreeze I would use and trust would be one from the manufacturer, in our case GM's Dexcool. I think more antifreeze manufacturers are paying closer attention to the issue but for me it more a matter of trust and assurance of what is in the container.

 

I agree but I would add that distilled water is theoretically a perfect 7.0 Ph, which means it is neither acidic or basic, and yet it will be aggressive and pull minerals from components in a water system, so this whole discussion is not simply an issue of Ph. Total alkalinity, total dissolved solids, calcium hardness all play a part. Also remember that the ruined shower heads and dishwashers are ruined by the minerals left by a long term flow of many thousands and thousands of gallons of water. The minerals in the cooling system are pretty much limited to the amount in a couple of gallons of water.