Originally Posted By: The Critic
Not true. Toyota does NOT recommend the usage of silicates in their coolants. The SLL coolant uses a dose of phosphates in addition to utilizing organic acid technology. It's technically a hybrid type coolant and it uses more than just organic acid technology for its protection system.
The fact that Toyota doesn't recommend silicates is why I suggested the G-05 meets the spirit, not the letter, of Toyota's recommendation.
The low silicate in G-05 serves basically the same purpose as the phosphate in the Toyota coolant.
Phosphate works okay in soft water, as in Japan, but not so well in hard water, as in many places in North America.
Given a choice between the Toyota formula and the G-05 formula, it is my own impression G-05 is overall a better choice.
If you're in a mixed fleet situation like I am, G-05 is without a doubt the better choice.