Flush or drain coolant

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1,677
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Southwest
Can't seem to dial up what must be a dozen old threads, sorry. First coolant change coming up on Ford 3.7L. I could have sworn that Ford didn't like flush--only drain. Can't find it in the manual though. What say you? Drain or flush and drain?
 

CT8

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15,407
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Idaho
First determine if a flush is needed? What does the coolant look like and peer into the radiator, Probably it has a degas bottle though.
 
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10,455
Location
USA
Drain the radiator, and use the Lisle funnel when refilling smile There is no need to flush it unless you went like 300k without ever changing it and it's sludged, or if you used the wrong coolant, or deathcool. But in 99% of cases there is no need to flush.
 

jimbrewer

Thread starter
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1,677
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Southwest
Thanks. I'm on schedule for the first change--60K miles. Don't quite know why the first is twice as long as subsequent changes.
 
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Santa Barbara, CA
Originally Posted By: jimbrewer
Thanks. I'm on schedule for the first change--60K miles. Don't quite know why the first is twice as long as subsequent changes.
They cannot guarantee the quality of coolant being added. In the factory it is controlled.
 
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10,455
Location
USA
Originally Posted By: jimbrewer
Thanks. I'm on schedule for the first change--60K miles. Don't quite know why the first is twice as long as subsequent changes.
Yup! A car that new definitely doesn't need a flush smile
 
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1,701
Location
'murica
Originally Posted By: SilverSnake
Trade it in on a Dodge. Coolant is 10 year/150K mile OAT.
Dodge coolant changes are free with all major engine work hornets
 
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237
Location
Albury, NSW
Since a fair amount of coolant hides in the heater core and in other coolant lines I always find a flush is better value. It ensures that 100% of the old coolant is gone, and that there is 0% chance of any weird coolant chemistry happening. Chrissfix did a good video on youtube. my technique is slightly different. After draining the coolant, I then run the garden hose into the bottom radiator hose and have the car run with the heater on until the discharge coming out the bottom of the radiator is clear. If your coolant system is dirty, disconnect the top radiator hose and have it discharge directly from here. Take the rad out and clean it. Once you're confident it's all clean, you can then choose to do a 'chemical flush.' If you do repeat the previous step to ensure all the flushing agent is removed, after following the directions of the chemical flush. Afterwards, fill with distiled water and run for a short while. Dump that. Refill with a coolant of your choice that meets the manufacturer specifications. (I personally like Nulon coolants here in Australia.) guaranteed 100% clean. No old coolant. But does make a mess from running a total loss coolant system during the cleaning phase smile Regards Jordan
 
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Messages
704
Location
Florida
Originally Posted By: Ethan1
Originally Posted By: SilverSnake
Trade it in on a Dodge. Coolant is 10 year/150K mile OAT.
Dodge coolant changes are free with all major engine work hornets
Let see, in the last 50+ years I have owned 87 cars and trucks almost all GM, Ford, or Chrysler products. Never had any major engine issues except with Fords (specifically Ford trucks). Had a lot of transmission issues with GM trucks. Have had no major engine or transmission issues with Dodge or Ram products and I don't have to worry much about coolant changes! One man's experience.
 
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1,195
Location
Missouri
Most important part of coolant flush or even drain and fill is to use distilled water. The premix should come already mixed with distilled. The concentrate still comes out to be significantly cheaper when mixed with an 88 cent gallon of great value distilled water.
 
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17,501
Location
Clovis, CA
Flush the coolant with the engine running ? Guys here tell me it's safe because the water pump has a sealed bearing, but in the old days if you tried to run the water pump with straight water, it would burn the pump up. The coolant, being as slippery as it is, was the oil for water pumps back in the day before sealed bearings came about. I'm still too scared to do it; I just drain and fill.
 
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