I think propylene glycol is used as an anti freeze in camper potable
water systems because it is supposedly non-toxic in the small quantities
that would be residual  in the water system after a flush and refill
with fresh water in the spring time.

In any case this is not the stuff for your vehicle. Stick to spec or
there is trouble ahead.

Regards,

John Rodgers
88 GL Driver

Joe Glisson wrote:

>I am using the Prestone Low Tox brand coolant (propylene glycol) - it's the
>one that's less toxic to dogs and cats. I may be wrong but my understanding
>is that this brand is phosphate free and the color is green. The auto parts
>store folks assure me it is phosphate free and the container states it
>protects alum heads - if anyone has different info I'd sure like to hear
>about it. Joe
>
>
>