G Morse

I have a 2007 C6. What is the procedure for flushing the cooling system? Has anyone done this yourself? How involved is It? Thanks for any help or suggestions.

Kenny94945

I done it myself and had shops do it.

Because of the mess....shop is the way to go. They have a recycling machine/ tool specific for this job.

Else, open the radiator drain. Don't worry about draining the block just drain from the rad.
Drain then fill with water. Start car until thermostat opens (turn off car) and drain again - repete until you get clear water draining out of the rad.

Remove and empty/ clean the overflow tank.

Fill with distilled water (foregoing the debate on distilled vs tap) and Dexcool 50/50 ratio directly into rad slowly watch for air bubbles (and squeeze the lower and upper hoses to help eliminate bubbles once filled) top off through overflow tank.

That is a briefing from my memory. Not very difficult. I think shops charges about $175 and DIY cost may be $50 plus the hazadous waste transportation.

AORoads

I assume you mean mix straight concentrate Dexcool with straight distilled water in a 50/50 ratio (they do make a 50/50 Dex which is pre-mixed, so if you mixed that formula with distilled water, you'd dilute the Dex below what's needed). also, I thought all coolant is added to the overflow tank.

Bill Suttie

Just remember if you are draining and flushing yourself, dumping the old coolant in the street is a major no no. Collect all old coolant and recycle.

WHT

Unless your cooling system has been compromised, it probably does not need to be flushed. Dex-Cool runs clean in a well maintained aluminum cooling system (aluminum engine and radiator) and does not produce the precipitants and scale caused by older coolants and/or systems that contained more iron and copper. For example, the silicate drop out that occurred in the past after the coolant was "spent" and its inhibitors dropped out of solution.

The corrosion inhibitors in OAT coolants are slower acting and much longer-lived than those in traditional coolants. And, they are designed to protect metal parts by forming a thin protective skin over the aluminum. Flushing the system will disturb or remove this protective skin and it will have to slowly reform after flushing.

Only use clean water or a lower concentration of Dex-Cool if you do decide to flush the system. Do NOT use one of the chemical flush products.

G Morse

Thanks for the great responses. I now have the necessary info with which I can make an informed decision.

WHT

If you will be doing the work yourself, check out the Uview 550000 Airlift at Amazon. About $104 and it makes changing coolant very easy (and, there will be no air in the system afterwards). The Uview will also pressure check the cooling system.