Mixing Engine Coolants

[ViPER1313]

As I was driving to work yesterday, the low coolant light on my dash came on (it was a cold morning and the coolant level was marginal in the overflow tank.) Are there any compatibility issues between Havoline Extended Life (orange) coolant and the old fashioned green stuff? I added a 50/50 mix of the orange into my overflow tank (about 20oz total). If this mix will cause problems I will go and get the whole system flushed.

The orange stuff is also rated as Ford ESE M97B44-D compatible (compared to ESE M97B44-A that the SHO manual recommends) and on its product page ( http://www.havoline.com/products/na/antifreeze_01.html ) is quoted as being "Compatible with conventional antifreeze. Dilution with conventional antifreeze will reduce extended life benefits."

Any help would be much appreciated.

 

[rangerj]

The two coolants do NOT mix. If non of the orange coolant got into the green stuff then you should only have to flush out the overflow bottle. rangerj