For the first coolant drain & fill on a newer car my mechanic advised to forget the 5 year / 100K mile coolant claims and instead just drain & fill every 2 to 3 years max and you will most likely never see a coolant related failure ... Seems easy enough to do - your thoughts and experiences on subsequent coolant drain & fill schedule after first coolant service ?
Coolant Drain & Fill Schedule ?
- Thread starter ChrisD46
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I would also recommend that you use a coolant vac tool to replace the coolant. Many of these newer aluminum engines with siamesed bores can be hard to get the air completely out of the system if you just let gravity fill the system.
[QUOTE="I For a random, run of the mill Hyundai, the 5yrs/100k would be more than fine.
[/QUOTE]
Coolant might outlast the engine, anyway.
[/QUOTE]
Coolant might outlast the engine, anyway.
I do D/F every 2-3 years, quick, easy and cheap to do, refreshes 1/2 of volume or so.
I do 100k miles. For me that ends up to be ~3.5 years. The coolant still looks good coming out of the system without any debris or signs of major corrosion in the cooling loop.
Your mechanic's advice sounds very old school. Or, his advice may be based upon using the cheaper, more basic varieties of coolant.
Coolants available today are much better than those of even 15 -20 years ago. If you use the right coolant for your engine type, they will protect it from corrosion for a very long time. Most all modern coolants are rated for at least 100k miles. Unless you are careless about using the correct coolant, and don't do a good flush before filling, there is no reason to do a coolant flush & fill early.
Coolants available today are much better than those of even 15 -20 years ago. If you use the right coolant for your engine type, they will protect it from corrosion for a very long time. Most all modern coolants are rated for at least 100k miles. Unless you are careless about using the correct coolant, and don't do a good flush before filling, there is no reason to do a coolant flush & fill early.
I take it, the mechanic is saying, drain the system to the extent that it will come out, which usually means what’s in the rad but not what’s left in the block below the level of the water pump. Then, fill the rad with pre-mixed coolant or a water/concentrate mixture. Not all the old coolant gets removed. The mechanic recommends compensating for this by doing the drain early. This will probably work and we did it like that on a friend’s Acura.
Having said that, I’ve been changing every 5 years, diluting the existing coolant in the block with water, running the engine until it heats up, then draining, and then adding enough concentrate to bring everything to 50/50. The vehicle has had this done twice and is approaching a third time at 15 years. No problems and it still has the original water pump. For the next change I might use the simple method and just drain and fill, knowing my coolant has been kept up to date for the last 15 years.
One other place where a simple drain and fill is convenient is with GM LS engines with no drain plug on the rad. You have to disconnect the lower rad hose, and it’s a PITA to have to reconnect the hose to run the engine with the flush water, then disconnect it again for the final drain.
Having said that, I’ve been changing every 5 years, diluting the existing coolant in the block with water, running the engine until it heats up, then draining, and then adding enough concentrate to bring everything to 50/50. The vehicle has had this done twice and is approaching a third time at 15 years. No problems and it still has the original water pump. For the next change I might use the simple method and just drain and fill, knowing my coolant has been kept up to date for the last 15 years.
One other place where a simple drain and fill is convenient is with GM LS engines with no drain plug on the rad. You have to disconnect the lower rad hose, and it’s a PITA to have to reconnect the hose to run the engine with the flush water, then disconnect it again for the final drain.
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One would have to check the factory service manual but it’s possible a flush is no longer recommended. A simple drain and fill is what the dealer does now in many cases.
Mine gets changed at 3 years or 30k miles (old school) but never makes it to 30 k miles. My vehicles are older and I think time is harder than miles on coolant. Thinking of going to 5 years, but, we'll see.
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I stick to around 100,000 miles on the factory fill, the I do simple drain and fills every two years after that.
I find that coolant is pretty good nowadays, and it’s rare for me to see “bad coolant” with these extended life coolants in a properly running engine.
I find that coolant is pretty good nowadays, and it’s rare for me to see “bad coolant” with these extended life coolants in a properly running engine.
Modern coolant should be in principle good for longer, but my 2011 Hyundai specs a 5 yr initial and 2 yrs thereafter coolant change interval. What's even more frustrating is they don't say what the coolant type is so I've just been going to the dealership and getting their recommended OE coolant. I have no idea what it is so I just change it every 2 years even though it's likely overkill.
I was surprised, as per my post below, that my wife's 17 with only 60,000 kms (37,000 miles) is on the weak/discolored side. I honestly thought with such low mileage, I had a ways to go yet but was equally surprised the recommendation was 5yrs or that mileage, whichever came first.
