I do 30k mi. drain and fills on all our transmissions. Would it be overkill to drain and fill the coolant every 30k? I changed the coolant on one of our Vibes last July 2018 at 90k mi. Now I'm at 120k mi.
Is 30k mi. Coolant drain and fills overkill?
- Thread starter Nicasio
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I usually change coolant based on time, typically every 2-3 years. A lot of newer cars come with extended life coolants recommended to change every 5-10 years. If you use the old green stuff, every 30k miles might be appropriate.
I drain and refill the coolant on older cars that use the old green coolant every 6-7 years or 100,000 miles. Usually I let it go longer than that and they are spotless inside. I had a 19 year old
![[Linked Image]](https://www.bobistheoilguy.com/forums/attachments/usergals/2019/02/full-66107-30638-sdc10021.jpg "[Linked Image]")
rad start leaking due to exterior salt corrosion a year ago and I cut the old rad apart to see what it was like inside.
rad start leaking due to exterior salt corrosion a year ago and I cut the old rad apart to see what it was like inside.
6-7 yrs and 100K miles on green coolant could show a nice clean radiator. What you won't know is the corrosive activity occurring in the engine's cooling system which is just cast steel. I can't see how green coolant that old wouldn't drop to a low pH and become fairly corrosive. The low pH can set up a current flow in the engine via a galvanic cell, ultimately affecting critical engine parts.
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I used to do it every 2-3 years or 40k miles but now I do it when it looks like it needs to be done and/or I can't remember when it was done last or I have an issue. My Cutlass was running hot on the highway with AC on (over 220 on a hot day). The coolant was starting to look bad. Flushing it several times fixed it completely.
I had changed it regularly over the 6-7 years before that but the engine probably had some major buildup in the coolant passages as it had been sitting in the junkyard probably 10+ years before I got it.
The Caprice seems to stay clean for a good few years. It's always been a daily driver for at least 2/3 of the year and the previous owner had the coolant flushed once.
Both are plain old green coolant (1980s cars). The Cutlass has a 1976 350 Olds with an aftermarket aluminum intake. The aluminum seems like it may cause the coolant to dirty up faster. The intake gasket failed after about 9 years and there was pitting on the intake which caused that.
I had changed it regularly over the 6-7 years before that but the engine probably had some major buildup in the coolant passages as it had been sitting in the junkyard probably 10+ years before I got it.
The Caprice seems to stay clean for a good few years. It's always been a daily driver for at least 2/3 of the year and the previous owner had the coolant flushed once.
Both are plain old green coolant (1980s cars). The Cutlass has a 1976 350 Olds with an aftermarket aluminum intake. The aluminum seems like it may cause the coolant to dirty up faster. The intake gasket failed after about 9 years and there was pitting on the intake which caused that.
Originally Posted by WobblyElvis
Radiator starts leaking due to exterior salt corrosion a year ago and I cut the old rad apart to see what it was like inside.
Seriously ? That's the first time I heard of a radiator rotting from the outside.
Radiator starts leaking due to exterior salt corrosion a year ago and I cut the old rad apart to see what it was like inside.
Seriously ? That's the first time I heard of a radiator rotting from the outside.
Originally Posted by Warstud
Originally Posted by WobblyElvis
Radiator starts leaking due to exterior salt corrosion a year ago and I cut the old rad apart to see what it was like inside.
Seriously ? That's the first time I heard of a radiator rotting from the outside.
Well I'm in the salt belt and there is a steel rail or brace going along the bottom of the rad and the rad was 19 years old. There was an area that was caked with brown and green goo and that's where it was leaking. I didn't power wash it or examine it to closely but I assume it was an exterior corrosion causing the leak. Considering the age of the radiator I wasn't complaining about changing it. This vehicle is a 99 dodge caravan and I've had a few of them. First rad leak. I have had to change a thermostat or two and every time I look inside the housing I fail to see any signs of corrosion. This is pretty well the only time I change any of the coolant. I can't remember ever changing a rad hose either.
Originally Posted by WobblyElvis
Radiator starts leaking due to exterior salt corrosion a year ago and I cut the old rad apart to see what it was like inside.
Seriously ? That's the first time I heard of a radiator rotting from the outside.
Well I'm in the salt belt and there is a steel rail or brace going along the bottom of the rad and the rad was 19 years old. There was an area that was caked with brown and green goo and that's where it was leaking. I didn't power wash it or examine it to closely but I assume it was an exterior corrosion causing the leak. Considering the age of the radiator I wasn't complaining about changing it. This vehicle is a 99 dodge caravan and I've had a few of them. First rad leak. I have had to change a thermostat or two and every time I look inside the housing I fail to see any signs of corrosion. This is pretty well the only time I change any of the coolant. I can't remember ever changing a rad hose either.
I want to say at least a few manufacturers are recommending 10 years 100,000 on the ORIGINAL fill, but after that the intervals are reduced. I think Toyota reduces there's to 50,000 after that first 100,000...I've read 30,000 on another.
So I would think simple 30,000 mile drain and fills are appropriate after that first coolant change. That's what I've done in the past, plus simple drain and fills usually only are using like a gallon/gallon and a half of coolant. I'd definitely go OE on the coolant though, those all makes all models are supposed to go into a system that has had all of the previous fluid removed (not easy to do sometimes).
So I would think simple 30,000 mile drain and fills are appropriate after that first coolant change. That's what I've done in the past, plus simple drain and fills usually only are using like a gallon/gallon and a half of coolant. I'd definitely go OE on the coolant though, those all makes all models are supposed to go into a system that has had all of the previous fluid removed (not easy to do sometimes).
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Originally Posted by Railrust
I want to say at least a few manufacturers are recommending 10 years 100,000 on the ORIGINAL fill, but after that the intervals are reduced. I think Toyota reduces there's to 50,000 after that first 100,000...I've read 30,000 on another.
So I would think simple 30,000 mile drain and fills are appropriate after that first coolant change. That's what I've done in the past, plus simple drain and fills usually only are using like a gallon/gallon and a half of coolant. I'd definitely go OE on the coolant though, those all makes all models are supposed to go into a system that has had all of the previous fluid removed (not easy to do sometimes).
I believe the reduced follow-on intervals is because the coolant change only includes draining and refilling the rad.
I want to say at least a few manufacturers are recommending 10 years 100,000 on the ORIGINAL fill, but after that the intervals are reduced. I think Toyota reduces there's to 50,000 after that first 100,000...I've read 30,000 on another.
So I would think simple 30,000 mile drain and fills are appropriate after that first coolant change. That's what I've done in the past, plus simple drain and fills usually only are using like a gallon/gallon and a half of coolant. I'd definitely go OE on the coolant though, those all makes all models are supposed to go into a system that has had all of the previous fluid removed (not easy to do sometimes).
I believe the reduced follow-on intervals is because the coolant change only includes draining and refilling the rad.
Originally Posted by Nicasio
I do 30k mi. drain and fills on all our transmissions. Would it be overkill to drain and fill the coolant every 30k? I changed the coolant on one of our Vibes last July 2018 at 90k mi. Now I'm at 120k mi.
Yes...ridiculously short interval.
I do 30k mi. drain and fills on all our transmissions. Would it be overkill to drain and fill the coolant every 30k? I changed the coolant on one of our Vibes last July 2018 at 90k mi. Now I'm at 120k mi.
Yes...ridiculously short interval.
I'd vote for time. I've done two five year terms with Dexcool on a 2008 Chev suburban with180,000 miles. At both changes the coolant looked faded but there were no corrosion products.
On my 2000 Taurus I have gone through 3 five year periods. One with the original coolant, and two with normal yellow Prestone Longlife. Currently 150,000 miles. No corrosion products. Both vehicles have their original rads.
YRMV.
On my 2000 Taurus I have gone through 3 five year periods. One with the original coolant, and two with normal yellow Prestone Longlife. Currently 150,000 miles. No corrosion products. Both vehicles have their original rads.
YRMV.
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I went 110k miles / 7 years before changing the coolant on my F150. Now yearly with Dexcool. Old coolant looked fine.
Originally Posted by Nicasio
I do 30k mi. drain and fills on all our transmissions. Would it be overkill to drain and fill the coolant every 30k? I changed the coolant on one of our Vibes last July 2018 at 90k mi. Now I'm at 120k mi.
IMO that mileage is too low and it's only 1 year old. If it took 10 years to drive 30 k then that is something different. Why not buy some coolant test strips?
I normally do it every 5-6 years for my mileage.
I do 30k mi. drain and fills on all our transmissions. Would it be overkill to drain and fill the coolant every 30k? I changed the coolant on one of our Vibes last July 2018 at 90k mi. Now I'm at 120k mi.
IMO that mileage is too low and it's only 1 year old. If it took 10 years to drive 30 k then that is something different. Why not buy some coolant test strips?
I normally do it every 5-6 years for my mileage.
I go by years, not miles. I test the coolant to be sure it's OK.
Vibes use Dexcool which is a fine coolant when its fresh. Acidic sludgy death when its old and oxidized. So yes, change it at 30k.
I do as well.
I do as well.
Originally Posted by Warstud
Originally Posted by Nicasio
Would it be overkill to drain and fill the coolant every 30k?
Depends on the coolant you use. What coolant do you use ?
Zerex Asian Red stuff
Originally Posted by Nicasio
Would it be overkill to drain and fill the coolant every 30k?
Depends on the coolant you use. What coolant do you use ?
Zerex Asian Red stuff
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