Engine Coolant
Thread Starter
Instructor
Joined: Dec 2004
Posts: 168
Likes: 1
Engine Coolant
I am curious about what you guys think I should do.
My C6 is 5 years old, only about 18,000 miles, mostly driven on the highway. The car is always in my garage.
The engine coolant is a bit low, can I just add some 50/50 coolant/water mix or should I definitely have it flushed out?
My C6 is 5 years old, only about 18,000 miles, mostly driven on the highway. The car is always in my garage.
The engine coolant is a bit low, can I just add some 50/50 coolant/water mix or should I definitely have it flushed out?
Race Director
Joined: Feb 2006
Posts: 11,733
Likes: 15
From: SC
I am curious about what you guys think I should do.
My C6 is 5 years old, only about 18,000 miles, mostly driven on the highway. The car is always in my garage.
The engine coolant is a bit low, can I just add some 50/50 coolant/water mix or should I definitely have it flushed out?
My C6 is 5 years old, only about 18,000 miles, mostly driven on the highway. The car is always in my garage.
The engine coolant is a bit low, can I just add some 50/50 coolant/water mix or should I definitely have it flushed out?
I just did it this morning, needed 2 jugs of 50/50 dexcool from walmart total cost $22. Drained and refilled. I was also at the 5 yr mark and decided might as well do it.
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Le Mans Master
Joined: Aug 2007
Posts: 7,250
Likes: 6
From: Glassboro New Jersey
From my experience as an auto tech, I would recommend using Prestone Dex Cool.
There have been a lot of problems with GM Dex Cool in the past, like corroding and clogging radiators and heater cores.
I never saw any issues with Prestone Dex Cool.
There have been a lot of problems with GM Dex Cool in the past, like corroding and clogging radiators and heater cores.
I never saw any issues with Prestone Dex Cool.
Team Owner
Joined: Sep 2000
Posts: 25,002
Likes: 2,703
From: Far NW 'burbs of Chicago
St. Jude Donor '13
Before flushing/replacing the coolant, I'd want to know why it went down. In theory, it should never need any additional. In practice, a cupful a year is not uncommon.
Depending on how much/how fast yours went down, you might want the system pressure tested to see if there is a problem.
Good luck with yours.
Depending on how much/how fast yours went down, you might want the system pressure tested to see if there is a problem.
Good luck with yours.
Le Mans Master
Joined: Aug 2007
Posts: 7,250
Likes: 6
From: Glassboro New Jersey
Thread Starter
Instructor
Joined: Dec 2004
Posts: 168
Likes: 1
I would do it myself, but I have no way to lift the car. I need to lift it to drain the coolant, right?
My local GM dealer wants $200 for it, the local Valvoline asks $100, but I doubt either one runs water in it first to clean it and then adds the coolant as I read in some posts before.
My local GM dealer wants $200 for it, the local Valvoline asks $100, but I doubt either one runs water in it first to clean it and then adds the coolant as I read in some posts before.
Instructor
Joined: Dec 2007
Posts: 132
Likes: 0
From: Owasso OK
I would do it myself, but I have no way to lift the car. I need to lift it to drain the coolant, right?
My local GM dealer wants $200 for it, the local Valvoline asks $100, but I doubt either one runs water in it first to clean it and then adds the coolant as I read in some posts before.
My local GM dealer wants $200 for it, the local Valvoline asks $100, but I doubt either one runs water in it first to clean it and then adds the coolant as I read in some posts before.
I flushed mine a couple of times with distilled water and one thing that I didn't expect was how long it took to fill the system. Draining wasn't very fast either. I flushed with distilled water 2 times, and if I had more time I would have flushed it once or twice more to get all the old coolant out.
Thread Starter
Instructor
Joined: Dec 2004
Posts: 168
Likes: 1
You don't need a lift. It's hard to see the drain plug, but it's not hard to reach it from the passenger side. Also, you need a drain pan that fits under your air dam.
I flushed mine a couple of times with distilled water and one thing that I didn't expect was how long it took to fill the system. Draining wasn't very fast either. I flushed with distilled water 2 times, and if I had more time I would have flushed it once or twice more to get all the old coolant out.
I flushed mine a couple of times with distilled water and one thing that I didn't expect was how long it took to fill the system. Draining wasn't very fast either. I flushed with distilled water 2 times, and if I had more time I would have flushed it once or twice more to get all the old coolant out.
Where can I find a good guide to do it myself?
Instructor
Joined: Dec 2007
Posts: 132
Likes: 0
From: Owasso OK
Change coolant every 5 years or 150,000 miles, which ever comes first.
Buy 2 gals Prestone Dex Cool (Walmart) and 6 gals distilled water. I used 5 gals of distilled water this year and flushed it twice. I think three flushes would have been better.
1) Drain coolant (drain plug is on passenger side). Approx. 8 qts out of 12.6 qts will actually drain.
2) Refill surge tank to the neck with distilled water. It will take a while to replace the 8 qts or whatever was drained.
3) Start engine, idle 4 min
4) Top off surge tank
5) Rev engine at 2000-2500 rpm for 2 more min. (temp should reach ~200 F)
6) Shutoff engine, cool for 20 minutes
7) Repeat steps 1-6 until fluid drains clear (2-4 flushes)
8) Refill with 6.3 qts Dex Cool (it's a slow process) and then top off with distilled water.
9) Repeat steps 3-5, take test drive, refill as necessary with distilled water.
10) Dispose of your old antifreeze at a recycling center.
Race Director
Joined: Dec 2010
Posts: 18,090
Likes: 1,574
I would do it myself, but I have no way to lift the car. I need to lift it to drain the coolant, right?
My local GM dealer wants $200 for it, the local Valvoline asks $100, but I doubt either one runs water in it first to clean it and then adds the coolant as I read in some posts before.
My local GM dealer wants $200 for it, the local Valvoline asks $100, but I doubt either one runs water in it first to clean it and then adds the coolant as I read in some posts before.
Drifting
Joined: Dec 2010
Posts: 1,939
Likes: 2
From: Danielsville Georgia
I just had mine done at a Chevy store. 2006 with 20k. I went in to inquire about what they did and prices. They just got a new BG cooling system machine. I had a two trucks done with same machine a few months back at another shop.. Its pretty trick. It uses vacuum and sucks every bit of fliud,crud out of the cooling system,heater core etc. Then they cleaned overflow tank added about two gallons of Dex cool. $89.95
Thread Starter
Instructor
Joined: Dec 2004
Posts: 168
Likes: 1
I just had mine done at a Chevy store. 2006 with 20k. I went in to inquire about what they did and prices. They just got a new BG cooling system machine. I had a two trucks done with same machine a few months back at another shop.. Its pretty trick. It uses vacuum and sucks every bit of fliud,crud out of the cooling system,heater core etc. Then they cleaned overflow tank added about two gallons of Dex cool. $89.95
Drifting
Joined: Dec 2010
Posts: 1,939
Likes: 2
From: Danielsville Georgia
The Chevy store near me has been pretty much in line or better then the independents around here and quickie lubes. They know their competition on maintance items.. Now the Dodge store is outrageous on maintance items. I know the guys there really well and have for a number of years. I tell them often you can't base maintenance items on $90 bucks flat rate Some of their services are outta site price wise. They don't do much of it either. They say they tell the owners that often and it goes in one ear and out the other.
Last edited by Ketchum; Apr 17, 2011 at 01:11 PM.
Racer
Joined: Dec 2007
Posts: 417
Likes: 10
From: Orlando Florida
great process steps....one extra
Here are my notes that I gathered from the forum:
Change coolant every 5 years or 150,000 miles, which ever comes first.
Buy 2 gals Prestone Dex Cool (Walmart) and 6 gals distilled water. I used 5 gals of distilled water this year and flushed it twice. I think three flushes would have been better.
1) Drain coolant (drain plug is on passenger side). Approx. 8 qts out of 12.6 qts will actually drain.
2) Refill surge tank to the neck with distilled water. It will take a while to replace the 8 qts or whatever was drained.
3) Start engine, idle 4 min
4) Top off surge tank
5) Rev engine at 2000-2500 rpm for 2 more min. (temp should reach ~200 F)
6) Shutoff engine, cool for 20 minutes
7) Repeat steps 1-6 until fluid drains clear (2-4 flushes)
8) Refill with 6.3 qts Dex Cool (it's a slow process) and then top off with distilled water.
9) Repeat steps 3-5, take test drive, refill as necessary with distilled water.
10) Dispose of your old antifreeze at a recycling center.
Change coolant every 5 years or 150,000 miles, which ever comes first.
Buy 2 gals Prestone Dex Cool (Walmart) and 6 gals distilled water. I used 5 gals of distilled water this year and flushed it twice. I think three flushes would have been better.
1) Drain coolant (drain plug is on passenger side). Approx. 8 qts out of 12.6 qts will actually drain.
2) Refill surge tank to the neck with distilled water. It will take a while to replace the 8 qts or whatever was drained.
3) Start engine, idle 4 min
4) Top off surge tank
5) Rev engine at 2000-2500 rpm for 2 more min. (temp should reach ~200 F)
6) Shutoff engine, cool for 20 minutes
7) Repeat steps 1-6 until fluid drains clear (2-4 flushes)
8) Refill with 6.3 qts Dex Cool (it's a slow process) and then top off with distilled water.
9) Repeat steps 3-5, take test drive, refill as necessary with distilled water.
10) Dispose of your old antifreeze at a recycling center.
The process steps are accurate and will work sufficently for the out come you seek. I use exactly the same procedure when I changed out my coolant on my 2005 at 53,000 miles. However I suggest you do 2 more simple steps:
1. before dumping the old coolant drive your car normally so it is at normal operating temperature and RECORD this value.
2. After you have drained the fluid and recirculated the water through the system (step #2) and if you have the time, remove the surge tank and clean out the excess sluge and contaiments.
The extra 2 steps is just me.
Good luck
Mike