Forum Discussion
wolfe10
Apr 12, 2016Explorer
There are several different chemistries of approved coolants for large diesels:
Low siliate for diesel with added SCA (Supplemental Cooling Additive). Sometimes referred to as DCA (Diesel Cooling Addtive). This is the "regular" coolant and SCA/DCA level must be test and replenished (it is used up protecting the cylinder liners of linered engines. Most recommend 3 year replacement in addition to annual SCA/DCA testing and replenishment.
The new generation OAT based coolants. Think of them as "maintenance free" coolant. 6 years, put them in and forget about them. Yes, if you drive more than 300,000 miles during that time, you have to add a one time booster.
While I doubt your coolant will "turn into a pumpkin" if you mix them, you would have to have an advanced degree in chemistry and know the composition of each to predict what would happen if mixing coolants of different chemistries.
But, I guess my question is "Why would you even consider doing it"? Carry an extra gallon of what ever coolant you are using. If a regular coolant, also test annually with the test strips and have either a coolant filter with SCA/DCA or liquid SCA/DCA on hand.
Low siliate for diesel with added SCA (Supplemental Cooling Additive). Sometimes referred to as DCA (Diesel Cooling Addtive). This is the "regular" coolant and SCA/DCA level must be test and replenished (it is used up protecting the cylinder liners of linered engines. Most recommend 3 year replacement in addition to annual SCA/DCA testing and replenishment.
The new generation OAT based coolants. Think of them as "maintenance free" coolant. 6 years, put them in and forget about them. Yes, if you drive more than 300,000 miles during that time, you have to add a one time booster.
While I doubt your coolant will "turn into a pumpkin" if you mix them, you would have to have an advanced degree in chemistry and know the composition of each to predict what would happen if mixing coolants of different chemistries.
But, I guess my question is "Why would you even consider doing it"? Carry an extra gallon of what ever coolant you are using. If a regular coolant, also test annually with the test strips and have either a coolant filter with SCA/DCA or liquid SCA/DCA on hand.
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