2003 c5 vert
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Instructor
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From: Sea Girt NEW JERSEY
Thread Starter
Instructor
Joined: Oct 2005
Posts: 112
Likes: 0
From: Sea Girt NEW JERSEY
i wouldn't mix dexcool (likely what is in your c5) with anything but dexcool.
Therein lies the rub. It is extremely difficult to get all the coolant out of a c5. There are no block drains and about half the coolant is in the block. So even removing the lower radiator hose to drain as much as possible leaves a gallon to a gallon and a half in the block.
Allow me to adjust my flame suit.
There, all set.
I changed to a coolant other than dexcool a few years back and i used a process of draining the system, filling it with straight water, running the car until the t-stat opened to mix the water and coolant left in the block, draining the the system, filling it with straight water, running the car.......... I repeated the process 6 times in total before i felt the original coolant left in the block was as close to straight water as i could get.
Then i drained the system one last time. I added straight antifreeze until the system appeared full. I ran the car and burped the air and let the car cool. I tested the antifreeze concentration and it was a little above 50-50 favoring the antifreeze. I topped off with straight water.
I'm happy with the results.....................
Therein lies the rub. It is extremely difficult to get all the coolant out of a c5. There are no block drains and about half the coolant is in the block. So even removing the lower radiator hose to drain as much as possible leaves a gallon to a gallon and a half in the block.
Allow me to adjust my flame suit.
There, all set.
I changed to a coolant other than dexcool a few years back and i used a process of draining the system, filling it with straight water, running the car until the t-stat opened to mix the water and coolant left in the block, draining the the system, filling it with straight water, running the car.......... I repeated the process 6 times in total before i felt the original coolant left in the block was as close to straight water as i could get.
Then i drained the system one last time. I added straight antifreeze until the system appeared full. I ran the car and burped the air and let the car cool. I tested the antifreeze concentration and it was a little above 50-50 favoring the antifreeze. I topped off with straight water.
I'm happy with the results.....................
i am gona drain and replace all the coolant. The car is 10 yrs old, system never changed and has about 60k miles.
Thnx everyone who answered for all the help...
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Personally I would just drain and refill with Dex-Cool. It works well.
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