Preston Coolant

[sherqa]

I add 1 Galon of Preston Coolant in my Land Cruiser Radiator but still needed more so I added tap water, BUT later I saw its written on the gallon do not add water, do i need to empty the radiator again and fill with new collant or its OK because I can not see much difference in temperature guage reading

 

[Brett]

The coolant you've bought is probably premixed & shouldn't be diluted.

You'll find it is the corrosion inhibition that has been diluted not the cooling property as water cools better than coolant anyway.

If you're worried about corrosion, change it, if not it won't affect cooling.