Do you think most cars need a coolant flush anymore?
- Thread starter ZZman
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Well, maybe not for the first owner but certainly for the 2nd...or by the second owner if the vehicle is 8-10 yrs old.
TBH, I haven't done a coolant flush or even a drain and fill in decades. I get a jug of coolant at the dealership and keep the coolant recovery tank filled to the MAX line at all times. The caveat is this; These cars were bought new by me and were typically traded on by 8-10 years and 100,000 miles. I lost a water pump on a NISSAN pickup in the late 90's. Coolant was still clean and reused. Probably 10-12 other cars treated the same way with no problems. Coolant stayed pristine throughout. Brands included Ford, FCA, LR, Subaru (X2), MINI, Honda (X4) and Chevrolet. Your mileage may vary.
With old and heavily silicates coolants, a flush was needed so that the silicates would not start dropping out. Or to flush out anything that did drop out.
With new coolants that have either very little silicates or non at all, the name of the game is keeping the Ph and inhibitor levels in check. A radiator drain and fill, if done within the recommended time will accomplish this task without issues.
With new coolants that have either very little silicates or non at all, the name of the game is keeping the Ph and inhibitor levels in check. A radiator drain and fill, if done within the recommended time will accomplish this task without issues.
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No flush unless I see a problem, which I haven't. Drain and fill every 5 - 9 years. I keep my cars up to 20 years old without problems.
With timing belt cars.. whomever is doing the work usually does the water pump and a fluid drop is done. The timing chain cars probably never get a flush or drain unless someone gets a heads up from a dealer that its on the maintenance schedule.
Older people like my mom like to have their antifreeze checked every year before winter..
Older people like my mom like to have their antifreeze checked every year before winter..
You can probably get away with draining the rad and filling with 50/50 but since I try to get 200,00 miles out of my vehicles, I do three drains with distilled water between the first two (and run it with the heater on), then volume in with concentrated coolant after the third drain. I do this every five years.
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Drain and refill is all I've ever done.
When deciding, the risk is not so much the radiator, but the heater core. Getting down to the heater core on some vehicles is a nightmare.
This is why I've been very careful to use ONLY the exact specification coolant called out in the owner manual and sourced from dealership. By avoiding any self inflicted gumming up of the heater core or rad, I can usually skate by with few issues.
Originally Posted by ZZman
With coolants and materials being better now do you think a coolant flush is really needed anymore?
I can't tell you the last time I saw a really bad radiator.
I don't believe they do. I literally NEVER hear of coolant related issues anymore. So no, I never flush. But I am the same with ATF. Unless I own what I would call a marginal tranny, I don't change the fluid. I just inspect. If the fluid looks good, I leave it. Now if it is black and burnt....well then you have what I call a marginal tranny and maybe then drain and flushes might help a little. I prefer to own cars that have a track record of good design.
With coolants and materials being better now do you think a coolant flush is really needed anymore?
I can't tell you the last time I saw a really bad radiator.
I don't believe they do. I literally NEVER hear of coolant related issues anymore. So no, I never flush. But I am the same with ATF. Unless I own what I would call a marginal tranny, I don't change the fluid. I just inspect. If the fluid looks good, I leave it. Now if it is black and burnt....well then you have what I call a marginal tranny and maybe then drain and flushes might help a little. I prefer to own cars that have a track record of good design.
I drain and refill with OEM coolant at the specified miles. My cars require the first change at 100K (or 6 years?) and 50K thereafter. It's cheap and easy, as long as you can bleed it successfully and don't break anything in the process.
Drain and fill is what I do. I do tend to short change the interval though, as I don't bother with a full fluid exchange. Too many people go to high miles with no issue for me to think it's a big problem any more. But I think it's cheap insurance for me in case I wind up driving it for a long time.
Originally Posted by ZZman
I mean I can see the drain and fills.
Are you referring to the single drain and fills or the double and triple drain and fills?
Also, by flushing ,are you referring to the garden hose type? I certainly don't do those anymore.
I mean I can see the drain and fills.
Are you referring to the single drain and fills or the double and triple drain and fills?
Also, by flushing ,are you referring to the garden hose type? I certainly don't do those anymore.
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Don't either - just did the 2014 Fusion Hybrid - drained out all I could from the lower hose and then filled with fresh.
Fluid coming out looked great with 108k on the clock.
Fluid coming out looked great with 108k on the clock.
Originally Posted by Snagglefoot
Originally Posted by ZZman
I mean I can see the drain and fills.
Are you referring to the single drain and fills or the double and triple drain and fills?
Also, by flushing ,are you referring to the garden hose type? I certainly don't do those anymore.
Just drain radiator and fill with new.
Flush I mean trying to get all the old coolant out and alsi could mean using a hose, flush chemical etc...
Originally Posted by ZZman
I mean I can see the drain and fills.
Are you referring to the single drain and fills or the double and triple drain and fills?
Also, by flushing ,are you referring to the garden hose type? I certainly don't do those anymore.
Just drain radiator and fill with new.
Flush I mean trying to get all the old coolant out and alsi could mean using a hose, flush chemical etc...
OK, a simple drain and fill will get about 1/2 of the total existing coolant out ( depending on the vehicle), so if the new mixed coolant can replenish the anti-corrosion additives I guess it will do fine. Similar trains of thought exist with leaving an oil filter in place, or perhaps vacuuming out half of the transmission fluid during a change. It might do well enough.
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4WD
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Yeah I did it with concentrate and less distilled water so what went in was above 50:50 - hoping the chemicals should be rich enough …
Probably splitting hairs to debate cooling effects on that hybrid ...
Probably splitting hairs to debate cooling effects on that hybrid ...
Yes. Modern "super long life" coolants are excellent, but even with easy-driving habits (no towing, no hauling, no racing/autocross), the coolant still needs to be changed or at least refreshed periodically, as well as checking/replacing the thermostat and pressure cap. In fact, all automotive fluids eventually need to be freshened or changed. There is no such thing as "lifetime" fluids, this is a marketing gimmick used to sell vehicles by claiming "low maintenance."
On the Corvette I do a full coolant flush (radiator and engine block) every 4 years usually around 20-25k miles, even though I use the green long life coolant rated for 5 years or 150,000 miles. This service is based on time because it's driven only about 5k miles per year.
On the Tacoma I do a full flush every 50-60,000 miles which is around 3 years, using the pink Toyota SLLC stuff. This service is based on mileage because it is driven considerably more than the Corvette.
Both vehicles are fairly easy to service and the peace of mind is priceless on those 110F summer afternoons, knowing the cooling system is fresh and in good working condition.
On the Corvette I do a full coolant flush (radiator and engine block) every 4 years usually around 20-25k miles, even though I use the green long life coolant rated for 5 years or 150,000 miles. This service is based on time because it's driven only about 5k miles per year.
On the Tacoma I do a full flush every 50-60,000 miles which is around 3 years, using the pink Toyota SLLC stuff. This service is based on mileage because it is driven considerably more than the Corvette.
Both vehicles are fairly easy to service and the peace of mind is priceless on those 110F summer afternoons, knowing the cooling system is fresh and in good working condition.
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