Coolant Change 101
Got Diesel?
Joined: Jan 2004
Posts: 4,345
Likes: 21
Personally, I am the leave well enough alone when it comes to freeze plugs kind of guy. I flush with distilled water and run my motor (with the T-stat in) and just run it until it opens (now I don't use the VC-9 cleaner).
I am a "keep it simple stupid kind of guy" and if I can strip a plug I probably will... and if it's going to break.. it will.. and it will be when the dealer/parts counter is closed!!!
This is also why I flush every 50,000 miles with distilled water and use a by-pass coolant filter. It is 1/2 the recommended change interval and I have just never worried about it and only use the Ford premium gold coolant... and hopefully with only distilled water and fresh coolant every 50,000 miles, I am time and money ahead???
However, you can't go wrong using the cleaner and flushing like crazy... just use common sense and take your time... no matter what method you use... and some will depend on what kind of tap or well water you have at home.. some is better than others.
I am a "keep it simple stupid kind of guy" and if I can strip a plug I probably will... and if it's going to break.. it will.. and it will be when the dealer/parts counter is closed!!!
This is also why I flush every 50,000 miles with distilled water and use a by-pass coolant filter. It is 1/2 the recommended change interval and I have just never worried about it and only use the Ford premium gold coolant... and hopefully with only distilled water and fresh coolant every 50,000 miles, I am time and money ahead???
However, you can't go wrong using the cleaner and flushing like crazy... just use common sense and take your time... no matter what method you use... and some will depend on what kind of tap or well water you have at home.. some is better than others.
New User
Joined: Feb 2010
Posts: 8
Likes: 0
From: Boise
I just completed a coolant flush following these directions word for word and it worked perfectly. Thanks to everyone that has helped compile this and all the other wonderful walk-throughs on this site. I appreciate your expertise. Thanks 
Posting Guru
Joined: Oct 2006
Posts: 1,693
Likes: 7
From: Francestown, NH
I will be doing this, but not the Thermostat removal option.
On the heater controls, with the heater on high, where is the best place for the other ****, the a/c, max a/c or one of the other cab settings, or does it matter?
On the heater controls, with the heater on high, where is the best place for the other ****, the a/c, max a/c or one of the other cab settings, or does it matter?
Got Diesel?
Joined: Jan 2004
Posts: 4,345
Likes: 21
You want your setting set for "heater" or floor heat.
You want maximum coolant flow through your entire system including your heater core and to circulate everything.
I have never removed my T-stat and all is well (to much work and to risky for me)... this is why you have to drive in between each drain and refill to get everything back up to temp and to get the t-stat to open on its own.
Just make sure after you drain and refill, let your motor idle for a bit to purge the air... the first drain and fill will be the worst (was for me)... maybe drive down the street with the degas cap off but have a gallon ready to pour in and allow gas/air to escape. Then you can replace cap and drive for 10 minutes or so to get it up to temp and get the t-stat to open and circulate the coolant fully.
The key is to get the coolant to circulate each time fully as to fully dillute.. so each time you drain and refill it becomes clearer and clearer... to the point the last 1 or 2 times, it just looks like pure clean distilled water that is draining out!!!
Will take about 3 - 4 gallons each time you drain and refill... so keep track and buy enough distilled water. I buy 16 - 20 gallons of water to do my complete flush... and this leaves me with 2 - 3 left over in the end so I can top of my system when done.
Good luck.
You want maximum coolant flow through your entire system including your heater core and to circulate everything.
I have never removed my T-stat and all is well (to much work and to risky for me)... this is why you have to drive in between each drain and refill to get everything back up to temp and to get the t-stat to open on its own.
Just make sure after you drain and refill, let your motor idle for a bit to purge the air... the first drain and fill will be the worst (was for me)... maybe drive down the street with the degas cap off but have a gallon ready to pour in and allow gas/air to escape. Then you can replace cap and drive for 10 minutes or so to get it up to temp and get the t-stat to open and circulate the coolant fully.
The key is to get the coolant to circulate each time fully as to fully dillute.. so each time you drain and refill it becomes clearer and clearer... to the point the last 1 or 2 times, it just looks like pure clean distilled water that is draining out!!!
Will take about 3 - 4 gallons each time you drain and refill... so keep track and buy enough distilled water. I buy 16 - 20 gallons of water to do my complete flush... and this leaves me with 2 - 3 left over in the end so I can top of my system when done.
Good luck.
Laughing Gas
Joined: Feb 2003
Posts: 998
Likes: 23
From: Tennessee
I take it you are not using the VC9 to clean the system. When I used the VC9 at 53,000 miles it took 48 gallons of distilled water to make mine run clear again. Twelve flushes.
Got Diesel?
Joined: Jan 2004
Posts: 4,345
Likes: 21
My coolant has never changed color or looked anything but perfect "gold in color". I have never had an EGR cooler or oil cooler leak... so, I see no need to use VC-9 cleaner in my cooling system.
I have always done my flushes at 50,000 mile intervals... which was long before Ford issued a TSB on flusing or testing the cooling system prior to the initial 100,000 mile service they wrote in the manual... and prior to that, there was never any mention or need for VC-9 (at least that I knew of or that was ever mentioned on this site).
I have always flushed at 50,000 miles and installed my coolant filter at the first one... so I am pretty confident that my cooling system is clean... or so I hope?
Spending .95 - $1.00/gallon for distilled water and needing 20 gallons is withing my budget... but spending $48 for 48 gallons as you wrote above is more than I am willing to spend... at least every 50,000 miles.
For me, frequant flushing (1/2 the interval of what Ford recommends) with distilled water and fresh Premium Gold coolant and the use of a coolant filter is good enough for me.
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Laughing Gas
Joined: Feb 2003
Posts: 998
Likes: 23
From: Tennessee
No, I have never used the VC-9 cleaner.
My coolant has never changed color or looked anything but perfect "gold in color". I have never had an EGR cooler or oil cooler leak... so, I see no need to use VC-9 cleaner in my cooling system.
I have always done my flushes at 50,000 mile intervals... which was long before Ford issued a TSB on flusing or testing the cooling system prior to the initial 100,000 mile service they wrote in the manual... and prior to that, there was never any mention or need for VC-9 (at least that I knew of or that was ever mentioned on this site).
I have always flushed at 50,000 miles and installed my coolant filter at the first one... so I am pretty confident that my cooling system is clean... or so I hope?
It would not hurt to use the VC9. It is good that you have a coolant filter but it is designed to catch very small particles.
I flushed the first time at 40,000 and everything looked great. Ten thousande miles later the coolant [Motorcraft Premium Gold] looked as good as new. I still decided to use the VC9 just for safe measure. I too had never had an EGR or coolant leak. After using the VC9 it took 12 flushes to get the distilled water to run clear. I am glad I cleaned mine.
Spending .95 - $1.00/gallon for distilled water and needing 20 gallons is withing my budget... but spending $48 for 48 gallons as you wrote above is more than I am willing to spend... at least every 50,000 miles.
For me, frequant flushing (1/2 the interval of what Ford recommends) with distilled water and fresh Premium Gold coolant and the use of a coolant filter is good enough for me.
My coolant has never changed color or looked anything but perfect "gold in color". I have never had an EGR cooler or oil cooler leak... so, I see no need to use VC-9 cleaner in my cooling system.
I have always done my flushes at 50,000 mile intervals... which was long before Ford issued a TSB on flusing or testing the cooling system prior to the initial 100,000 mile service they wrote in the manual... and prior to that, there was never any mention or need for VC-9 (at least that I knew of or that was ever mentioned on this site).
I have always flushed at 50,000 miles and installed my coolant filter at the first one... so I am pretty confident that my cooling system is clean... or so I hope?
It would not hurt to use the VC9. It is good that you have a coolant filter but it is designed to catch very small particles.
I flushed the first time at 40,000 and everything looked great. Ten thousande miles later the coolant [Motorcraft Premium Gold] looked as good as new. I still decided to use the VC9 just for safe measure. I too had never had an EGR or coolant leak. After using the VC9 it took 12 flushes to get the distilled water to run clear. I am glad I cleaned mine.
Spending .95 - $1.00/gallon for distilled water and needing 20 gallons is withing my budget... but spending $48 for 48 gallons as you wrote above is more than I am willing to spend... at least every 50,000 miles.
For me, frequant flushing (1/2 the interval of what Ford recommends) with distilled water and fresh Premium Gold coolant and the use of a coolant filter is good enough for me.
Post Fiend
Joined: Jul 2005
Posts: 6,127
Likes: 6
You can run it, then pull a sample out to see how much it reacted with scale etc inside the system.
Need a lab... but even a visual inspection of debris and color change would be revealing.
Got Diesel?
Joined: Jan 2004
Posts: 4,345
Likes: 21
1) Truck was bougth new.
2) Truck has never had major mechanical issues.
3) Truck had radiator flushed and refilled at 50,000 miles with new coolant (by me).... which is 1/2 the interval that Ford recommends.
4) Installed Coolant filter.
5) Maintain flush intervals with distilled water and Ford Prem. Gold Coolant every 50,000 miles (by me).
6) Send oil samples to Blackstone Labs and have never had coolant leaks into oil or vice versa (never had oily residue in degas bottle or puking degas bottle).
7) Every drain and flush interval, coolant has always looked like normal gold color coolant... no rust or "off-color" to it.
So with that.... why would using VC-9 cleaner be recommended, advised or "cheap insurance"... or what kind of scale or deposits would be in there if my system (as far as I know) has never been exposed to hard water or bad "outside influences"?
Thanks,
Laughing Gas
Joined: Feb 2003
Posts: 998
Likes: 23
From: Tennessee
My coolant looked like new at 10,000 miles after the first change. After adding 2 qts of VC9 and driving a few miles, it came out coal black. After 12 flushes and 5000 more miles, the new coolant still looks good.
Hotshot
Joined: Dec 2003
Posts: 15,368
Likes: 121
From: Stuttgart, Ar
You might be real surprised what can grow and hide inside a cooling system even with the best of maintenance. Don't recall, but what do you use for gauges???
Laughing Gas
Joined: Feb 2003
Posts: 998
Likes: 23
From: Tennessee
How much scale and such can one have in their system if the following facts are known to exist:
1) Truck was bougth new.
2) Truck has never had major mechanical issues.
3) Truck had radiator flushed and refilled at 50,000 miles with new coolant (by me).... which is 1/2 the interval that Ford recommends.
4) Installed Coolant filter.
5) Maintain flush intervals with distilled water and Ford Prem. Gold Coolant every 50,000 miles (by me).
6) Send oil samples to Blackstone Labs and have never had coolant leaks into oil or vice versa (never had oily residue in degas bottle or puking degas bottle).
7) Every drain and flush interval, coolant has always looked like normal gold color coolant... no rust or "off-color" to it.
So with that.... why would using VC-9 cleaner be recommended, advised or "cheap insurance"... or what kind of scale or deposits would be in there if my system (as far as I know) has never been exposed to hard water or bad "outside influences"?
Thanks,
1) Truck was bougth new.
2) Truck has never had major mechanical issues.
3) Truck had radiator flushed and refilled at 50,000 miles with new coolant (by me).... which is 1/2 the interval that Ford recommends.
4) Installed Coolant filter.
5) Maintain flush intervals with distilled water and Ford Prem. Gold Coolant every 50,000 miles (by me).
6) Send oil samples to Blackstone Labs and have never had coolant leaks into oil or vice versa (never had oily residue in degas bottle or puking degas bottle).
7) Every drain and flush interval, coolant has always looked like normal gold color coolant... no rust or "off-color" to it.
So with that.... why would using VC-9 cleaner be recommended, advised or "cheap insurance"... or what kind of scale or deposits would be in there if my system (as far as I know) has never been exposed to hard water or bad "outside influences"?
Thanks,
My circumstances match yours with 2 exceptions. I don't have a coolant filter and have never sent oil samples for verification. With that said, my coolant was coal black after adding 2 qts of VC9, driving a few miles, and draining. I will add the VC9 to mine everytime I flush from now on. I plan on my truck lasting throughout my retirement years while pulling a fifth wheel. With no more miles than I pull with it that should not be a problem with proper maintenance. I know you are a fanatic about maintenance so you should "just do it".
Got Diesel?
Joined: Jan 2004
Posts: 4,345
Likes: 21
I use the following built-in custom gauges though:
1) "Seat-O'meter" gauge
2) "Hear-O'meter" gauge
3) "See-O'meter gauge
If I can see, feel or hear it... I have a good idea of what is going on with my truck... or so I think... that's my theory and I am stickinig too it!!!
