I drained radiator, vacuumed reservoir. Added prestone cleaner with water. Drove 2 hours-ish. Drained cleaner (it was quite dirty). Flushed radiator out with water until water was clear. Drained/vacuumed again. Started adding concentrate but was only able to add 1 gallon. From what I've read, I should have been able to add 1.5 gallons along with .5 gallons of water for 3 total (including the water that was left in the engine from the flush). Any thoughts on why I couldn't add the rest of the mixture? According to the procedures I've read, I'm not a little off. I'm way off. An entire gallon.

Having said that, I have now driven for about a week and have watched the temps/reservoir closely and no change. I'm just concerned the mixture is off. If there were actually 2 gallons of water in the system after the flush, then the mixture is ~66% water instead of 50% water.

 

Not a fan of flushing or cleaners. But 2 gal drain out of radiator is normal, and that is roughly half the total cooling system volume. So there's still 2 gal in there.

So yes you have diluted the cooling fluid.

I'd drain radiator, refill, drive, repeat, the radiator a couple times - refilling each time with 60% strength coolant to make up for the dilution.
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