Acceptable Coolant?

The Toyota coolant specification on page 589 of the Owner’s Manual (PDF) is “Toyota Super Long Life Coolant” (emphasis added), the pre-diluted, pink formulation; Toyota Long Life Coolant was the much earlier, red version. The Manual also states that “a similar high quality ethylene glycol based non-silicate, non-amine, non-nitrite, and non-borate coolant with long-life hybrid organic acid technology” can be used, and it notes that, in Canada, Toyota SLLC is a 55% coolant/45% water mixture.

I’m not sure I’d recommend it. DEX-COOL is a General Motors trademark, licensed for coolants that meet their specifications. Some of these have, or had, silicates, which Toyota prohibits, but I don’t know if Prestone’s does, nor whether it contains anything else that might react with Toyota SLLC or the other materials of the cooling circuits in undesirable ways.

Prestone’s website for Canada recommends their “Asian Vehicles (Red)” product for Prius Prime cars but also states that their “All Vehicles” products can be used. They don’t disclose the composition of any of these, so it’s not clear to me that there’s any difference other than the color and concentration, nor whether any of them actually meets Toyota’s stated requirements.

 

In a pinch, you can dump in distilled water - available almost anywhere. That should get you to a dealership or someplace that stocks a compatible coolant. You'll need to be careful in your Canadian winter, diluting your coolant too much may cause it to freeze.

Hope this helps.