Why do most new vehicles come with a long life coolant that can go 90,000 miles+ but then have to be changed much more frequently after the initial fill? My 2007 Nissan specifies 90,000 on the first run and after that every 30,000 miles, doesn’t make sense to me.
Coolant Change
- Thread starter MADMIKE
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I think it's because most people drain and refill which leaves a lot of old coolant in the system. You can remove even more coolant on most vehicles if you remove the block plug(s). I installed a block heater on my Subaru Impreza WRX. I drained the radiator first, but quite a bit of coolant came out of the engine when I removed a block plug.
Originally Posted By: MADMIKE
Why do most new vehicles come with a long life coolant that can go 90,000 miles+ but then have to be changed much more frequently after the initial fill? My 2007 Nissan specifies 90,000 on the first run and after that every 30,000 miles, doesn’t make sense to me.
First of all, I would not wait 90K miles... I would do a radiator drain and fill every 30K or 2 years.
Why do most new vehicles come with a long life coolant that can go 90,000 miles+ but then have to be changed much more frequently after the initial fill? My 2007 Nissan specifies 90,000 on the first run and after that every 30,000 miles, doesn’t make sense to me.
First of all, I would not wait 90K miles... I would do a radiator drain and fill every 30K or 2 years.
gathermewool
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Originally Posted By: Boss302fan
Originally Posted By: MADMIKE
Why do most new vehicles come with a long life coolant that can go 90,000 miles+ but then have to be changed much more frequently after the initial fill? My 2007 Nissan specifies 90,000 on the first run and after that every 30,000 miles, doesn’t make sense to me.
First of all, I would not wmait 90K miles... I would do a radiator drain and fill every 30K or 2 years.
I don't have any data to back this up, but my opinion is that the long-life coolants are good for their prescribed interval.
It is also my opinion that the shorter subsequent intervals are based on a radiator drain-and-refill, which replenishes only 1/3 of the additives.
I also believe that being dirty is not one of the reasons. In a well-maintained system (ie, not touched for the duration of the first interval,) an oxide layer should have formed and the coolant additives slowly depletes over time, which is the only reason the coolant needs to be replaced over time, in most circumstances. Without a head gasket issue, the only ingress of "dirt" would be from addition of distilled water or mixed coolant into the coolant reservoir (minimal.)
So, it is my opinion that the system should be touched for the full interval unless a known problem exists.
Originally Posted By: MADMIKE
Why do most new vehicles come with a long life coolant that can go 90,000 miles+ but then have to be changed much more frequently after the initial fill? My 2007 Nissan specifies 90,000 on the first run and after that every 30,000 miles, doesn’t make sense to me.
First of all, I would not wmait 90K miles... I would do a radiator drain and fill every 30K or 2 years.
I don't have any data to back this up, but my opinion is that the long-life coolants are good for their prescribed interval.
It is also my opinion that the shorter subsequent intervals are based on a radiator drain-and-refill, which replenishes only 1/3 of the additives.
I also believe that being dirty is not one of the reasons. In a well-maintained system (ie, not touched for the duration of the first interval,) an oxide layer should have formed and the coolant additives slowly depletes over time, which is the only reason the coolant needs to be replaced over time, in most circumstances. Without a head gasket issue, the only ingress of "dirt" would be from addition of distilled water or mixed coolant into the coolant reservoir (minimal.)
So, it is my opinion that the system should be touched for the full interval unless a known problem exists.
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I think part of the reason is the manufacturer cannot ensure that the end user used the proper coolant or water if the coolant is not a premix.
I just took my F150 to the dealer today and had the cooling system flushed. Ford says every 100k I went a little over 106k and it was time to change it. It wasn't nasty but it was dirty. In my humble opinion, you can't beat the flushing machines for cooling systems, it's really difficult to do as good a job in the drive way as you can with one of those machines.
Keep them clean by doing a drain and fill every 30K or 2-3 years...
gathermewool
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Originally Posted By: rodinator1234
I just took my F150 to the dealer today and had the cooling system flushed. Ford says every 100k I went a little over 106k and it was time to change it. It wasn't nasty but it was dirty. In my humble opinion, you can't beat the flushing machines for cooling systems, it's really difficult to do as good a job in the drive way as you can with one of those machines.
What do you mean when you say it was dirty? Was the coolant discolored, did it have particulates, etc?
I've changed the coolant in neglected systems and noted what looked like rust, both in the form of rusty-looking discoloration of the coolant, as well as particles.
I just took my F150 to the dealer today and had the cooling system flushed. Ford says every 100k I went a little over 106k and it was time to change it. It wasn't nasty but it was dirty. In my humble opinion, you can't beat the flushing machines for cooling systems, it's really difficult to do as good a job in the drive way as you can with one of those machines.
What do you mean when you say it was dirty? Was the coolant discolored, did it have particulates, etc?
I've changed the coolant in neglected systems and noted what looked like rust, both in the form of rusty-looking discoloration of the coolant, as well as particles.
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No it was just a discolored. Not really nasty bad, but not really translucent any more. Kind of like unfiltered wheat beer next to filtered Bud Light. I've seen way worse.
But to add, as long as the truck has been in service, the coolant reservoir cap has never been off. The cooling system was never opened up for adding coolant or any problems.
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