Upgrading from Dot 3 to Dot 4 – What is the difference?
Their primary differences are their wet & dry boiling points and their composition.
|Dry Boiling Point
||Wet Boiling Point
||Glycol Ether/Borate Ester
Check out this article by AmsOil to read more on the subject to see if DOT4 is the right upgrade for you.
DOT 3 and DOT 4 Brake Fluid: What’s the Difference? – AMSOIL Blog