Long Life Coolant Change Intervals?

[doitmyself]

What are the BITOG thoughts on change intervals for the newer long life coolants? My car has the new MOPAR oat coolant with 10 year, 150,000 mile change recommendation. I'm at 6.5 years and 85K miles and my OCD trigger finger is itching. I consider there are two change options: a radiator drain and fill (60% of system) or multiple water drain and fills to achieve a full (95%) replacement . The current coolant looks pristine, but I have not tested it beyond checking freeze point.

What are your opinions? In essence, I am considering a very easy option more often vs. a more time consuming option less often. Start now or wait until year 7 or 8? How often after the initial change? 3 or 4 years? I plan to stay with OEM coolant with distilled water.

Thanks!

 

[JamesBond]

On our Honda with the blue coolant I waited 5-6 years before the first radiator drain and fill. Since then I just drain and fill a gallon from the radiator every few years with Honda oe premix. The coolant and system always looks brand new.

 

[gathermewool]

I plan to follow the manual

 

[RamFan]

Simple radiator drain and fill. You're getting a majority of the fluid out that way and minimizing chance of air pockets and minimizing waste of good fluid.

I'd adhere to the manual length/mileage guidelines for the first one then scale back after that, every 5ish years. This is simply a precautionary measure, in reality you'd probably be fine keeping with the manual guidelines for the life of the vehicle.

As a side note, it's funny how you're given a 10 year cap while I'm given a 15 year cap on what is apparently the same fluid.

 

[Pelican]

All of these intervals are always calculated under "Ideal" conditions. I generally cut that interval in half.

 

[Ed_Flecko]

Here's a couple of good articles from AGCO Automotive on the topic: https://bit.ly/2XqXdly and https://bit.ly/2IMQ3UD

Ed

 

[gathermewool]

Originally Posted by Pelican
All of these intervals are always calculated under "Ideal" conditions. I generally cut that interval in half.



You mean like:

1. Coolant warms up to operating temperature band and stays there

2. Coolant cools down to ambient

3. Repeat

Is that what you mean?

 

[DGXR]

You'll be fine doing the easier radiator drain/fill about every 4-5 years. Even a "full drain" does not remove all the old coolant, so anyone who insists you must do that, well... we simply disagree. Just remember to change the cap and thermostat at the recommended intervals -- replacing these parts will get you a "full drain" often enough anyway.

 

[doitmyself]

Originally Posted by Ed_Flecko
Here's a couple of good articles from AGCO Automotive on the topic: https://bit.ly/2XqXdly and https://bit.ly/2IMQ3UD Ed

Ed, I love the AGCO "do it right" attitude. But man, they sure throw some curve balls.

In your first link: I wonder if some of their articles are out of date. For instance, they state that the original fill is good for five years and after the first change reduce the interval to 3 years. Does this take in to account today's coolants that recommend 10 years OEM fill?


The second link, wow, some crazy recommendations there.

The AGCO link states that some engines have no circulation in the lower part and added pure coolant will stratify there and not mix with water added separately,supporting a recent thread here asking about coolant not mixing inside the engine,

"With many engines, coolant flows only through the cylinder heads. The lower block fills with liquid but does not flow. Concentrated coolant can enter this area and remain there, because of its weight. Water with a smaller amount of coolant will circulate through the upper part of such a system. This promotes corrosion as the mixture is inadequate to protect the metal in the system. Play it safe by mixing the coolant and distilled water, before pouring them into the engine."

The second AGCO link also states that without block drains, the proper drain method is to do multiple drain and fills with coolant/water mix NOT pure water:

"When removing (all) the old coolant is not possible (block drains) - When removing at least 80% of the old coolant is not possible, we can repeat the procedure. Drain as much as possible and refill the system with coolant and distilled water. Next, with the heater on high, run the engine until it is normal temperature. Let the system cool and drain it again. This should get a much larger percentage of the depleted coolant out. Never use water for this purpose as it will only dilute the remaining coolant. This further reduces corrosion protection.""

Following their advice, most of us are doing it wrong.

 

[Ed_Flecko]

Originally Posted by doitmyself
Originally Posted by Ed_Flecko
Here's a couple of good articles from AGCO Automotive on the topic: https://bit.ly/2XqXdly and https://bit.ly/2IMQ3UD Ed

Ed, I love the AGCO "do it right" attitude. But man, they sure throw some curve balls.

In your first link: I wonder if some of their articles are out of date. For instance, they state that the original fill is good for five years and after the first change reduce the interval to 3 years. Does this take in to account today's coolants that recommend 10 years OEM fill?


The second link, wow, some crazy recommendations there.

The AGCO link states that some engines have no circulation in the lower part and added pure coolant will stratify there and not mix with water added separately,supporting a recent thread here asking about coolant not mixing inside the engine,

"With many engines, coolant flows only through the cylinder heads. The lower block fills with liquid but does not flow. Concentrated coolant can enter this area and remain there, because of its weight. Water with a smaller amount of coolant will circulate through the upper part of such a system. This promotes corrosion as the mixture is inadequate to protect the metal in the system. Play it safe by mixing the coolant and distilled water, before pouring them into the engine."

The second AGCO link also states that without block drains, the proper drain method is to do multiple drain and fills with coolant/water mix NOT pure water:

"When removing (all) the old coolant is not possible (block drains) - When removing at least 80% of the old coolant is not possible, we can repeat the procedure. Drain as much as possible and refill the system with coolant and distilled water. Next, with the heater on high, run the engine until it is normal temperature. Let the system cool and drain it again. This should get a much larger percentage of the depleted coolant out. Never use water for this purpose as it will only dilute the remaining coolant. This further reduces corrosion protection.""

Following their advice, most of us are doing it wrong.


I've listened to the AGCO Auto show for some time now and I have NO doubt that vehicles maintained by them probably run as well as they possibly can. Having said that, I agree as well that they are REALLY perfectionists and you probably have to temper their advice with a little common sense!

Ed

 

[atikovi]

Originally Posted by doitmyself
I consider there are two change options: a radiator drain and fill (60% of system) or multiple water drain and fills to achieve a full (95%) replacement . The current coolant looks pristine, but I have not tested it beyond checking freeze point.


If it makes you feel better, do a drain and refill now. Then a full multiple flush at the recommended time. If it looks pristine now, it's probably a waste of money though, as the additive package the manufacturer designs, should be good for the recommended intervals.

 

[gathermewool]

There's not much going on in a coolant system that requires a full exchange.

All you need to do is replenish the additives.

Whatever helps you sleep at night, though.

 

[BMWTurboDzl]

Originally Posted by Ed_Flecko
Originally Posted by doitmyself
Originally Posted by Ed_Flecko
Here's a couple of good articles from AGCO Automotive on the topic: https://bit.ly/2XqXdly and https://bit.ly/2IMQ3UD Ed

Ed, I love the AGCO "do it right" attitude. But man, they sure throw some curve balls.

In your first link: I wonder if some of their articles are out of date. For instance, they state that the original fill is good for five years and after the first change reduce the interval to 3 years. Does this take in to account today's coolants that recommend 10 years OEM fill?


The second link, wow, some crazy recommendations there.

The AGCO link states that some engines have no circulation in the lower part and added pure coolant will stratify there and not mix with water added separately,supporting a recent thread here asking about coolant not mixing inside the engine,

"With many engines, coolant flows only through the cylinder heads. The lower block fills with liquid but does not flow. Concentrated coolant can enter this area and remain there, because of its weight. Water with a smaller amount of coolant will circulate through the upper part of such a system. This promotes corrosion as the mixture is inadequate to protect the metal in the system. Play it safe by mixing the coolant and distilled water, before pouring them into the engine."

The second AGCO link also states that without block drains, the proper drain method is to do multiple drain and fills with coolant/water mix NOT pure water:

"When removing (all) the old coolant is not possible (block drains) - When removing at least 80% of the old coolant is not possible, we can repeat the procedure. Drain as much as possible and refill the system with coolant and distilled water. Next, with the heater on high, run the engine until it is normal temperature. Let the system cool and drain it again. This should get a much larger percentage of the depleted coolant out. Never use water for this purpose as it will only dilute the remaining coolant. This further reduces corrosion protection.""

Following their advice, most of us are doing it wrong.


I've listened to the AGCO Auto show for some time now and I have NO doubt that vehicles maintained by them probably run as well as they possibly can. Having said that, I agree as well that they are REALLY perfectionists and you probably have to temper their advice with a little common sense!

Ed


My guess is that Scotty Kilmer was the ghostwriter for these recommendations.

 

[dubber09]

Is it too much work or too expensive to drain and refill rad every 2-3 years? Even with long-life coolant?

 

[JunkdrawerDog]

I dunno...If the OEM stuff says it's good for 10 yrs and 150k, that's when I would change it. OP states he checked it for freezing point and presumably it was ok. What else is to be gained other than spending time and money on something that doesn't need to be done and contributes to the waste stream? I love it when people go on rants about "stealerships" trying to peddle unnecessary services then go home and double down on premature oil, filter, and coolant changes. Oh well. To each his own

 

[PandaBear]

When EVERYONE said it is good for 10 yr 150k on the initial factory fill (and usually 5 yr 50k afterward on refill), chances are good that it does last that long.

 

[willbur]

Originally Posted by doitmyself
What are the BITOG thoughts on change intervals for the newer long life coolants? My car has the new MOPAR oat coolant with 10 year, 150,000 mile change recommendation. I'm at 6.5 years and 85K miles and my OCD trigger finger is itching. I consider there are two change options: a radiator drain and fill (60% of system) or multiple water drain and fills to achieve a full (95%) replacement . The current coolant looks pristine, but I have not tested it beyond checking freeze point.

What are your opinions? In essence, I am considering a very easy option more often vs. a more time consuming option less often. Start now or wait until year 7 or 8? How often after the initial change? 3 or 4 years? I plan to stay with OEM coolant with distilled water.

Thanks!


I changed 11 and 15 year old OE coolant and both times coolant and the observable internal engine parts looked new. No sediment and crystal clear coolant. Even the coolant voltages were much lower than the suggested maximum for changing out. I asked myself- why am I doing this? Should have sent in samples for lab analysis. BITOG paranoia got to me, I guess. As usual, YMMV.

 

[doitmyself]

Us old guys remember the days of dirty scaled up radiators, corroded heater cores, grimy black air filters, and changing spark plugs and points every 15 K miles. Many here change their "lifetime" tranny fluid every 30 - 60K miles, but I understand the differences tranny fluids undergo vs. coolant.

It's good to hear that these 10 year automotive coolants seem to be up to the task. On my diesel ag. equipment, I upped the coolant change interval a LOT when the J.D. Coolgard II came out.

 

[Snowball]

I would drain and observe coolant. If it's not discolored and looks good i would add the appropriate coolant and mix and call it good for another 5 years. If its dirty looking I would do some flushes. I bet is it looks good and drain and fill will be fine. This oat and hoat coolants protect well and last a long time in most vehicles.

 

[Onetor]

Environmental issues certainly has a variable in the coolant interval.