One (1) Gallon of DCA4 (Diesel Coolant Additive)
One of the most commonly asked questions we get is regarding the necessity of SCA (Supplemental Coolant Additive). It is vital for the health and longevity of any diesel engine. Diesels, particularly the Ford Powerstroke, are prone to a problem called Cavitation (or liner pitting).
DCA4 is recommended for Ford Powerstroke, International Truck, and Cummins engines. For GM Duramax, Caterpillar, and Detroit Diesels, DCA2 is the required SCA.
Note: DCA4 is equivalent to Ford FW-16 (or new name VC-8)Problem: Cavitation
The pistons in your engine move up and down about 2,000 times a minute. While they move vertically, the crankshaft is performing a completely different movement by rotating horizontally. These contradictory movements will cause your engine’s liners to vibrate a lot. Although the outer wall of the liner is surrounded by cooling fluid, its inertia creates tiny vacuum pockets, causing bubbles of vapor to form on the liner wall. When the liner vibrates back, these bubbles collapse under an enormous pressure of about 1,000 bar, and take small chunks out of the liner. Eventually you will have block failure.
To prevent this, a supplemental coolant additive needs to be added to the cooling system. To check the SCA level you should periodically test your coolant using Fleetguard 3-Way test strips.
What is the proper chemical SCA concentration for diesel engines?
Basically a chemical concentration of 1.5 - 3.0 UPG (Units Per Gallon) should be maintained in your cooling system at all times. How do you achieve that? Well, this depends on the capacity of the coolant system. For a reference, a 1 pint bottle of DCA4 additive is equal to 5 units.
We recommend that you add up to 2.5 UPG if you don't test the SCA as often as you should. Keeping the level this high will help ensure that the level is at least 1.5 UPG. Ideally you should test the SCA every 4-6 months. If you do, then you can keep the level at a lower level of 2.0 UPG. The benefit of a lower level will help prevent the buildup of particles that SCAs often cause. This buildup can become loose or flake off the water jacket walls, and because it can be abrasive, it will cause damage to your water pump or even clog certain parts of the cooling system like the heater core. A preventative measure that can be taken to eliminate this is the use of a coolant filter.
Example of achieving the proper SCA level.
A 2001 Ford Powerstroke 7.3L has a capacity of 32.75 quarts or 8.2 gallons. To figure out how many units 1 pint of additive will raise the coolant level, divide the 5 units (the amount that 1 pint will give you) by the capacity in gallons (8.2) 5 divided by 8.2 = .61, so this tells you that each pint of additive will raise the coolant level to .6. So if your current level is now at 1.3 and you wish to reach a level of 2.5 you would need to add 2 pints (2pts x .6 = 1.2, 1.2 + 1.3 = 2.5)
Fleetguard part number: DCA70L