Sorry guys,probably not the correct place to post this thread but I tried in General Discussions and received no reply. I have a 93 7.3 IDI. I use Prestone 50/50 and NapaKool 4056 according to the instructions. Do I have any concerns about this mixture? It's been in there about a year. I only put about 10K a year on it.

 

Prestone green is fine, the napa cool is the SCA I assume..... use the NAPA test strips and keep the SCA levels as required.

I leave my coolant in several years at a time unless I get a problem with rad/heater core/water pump/Tstat etc. If it looks clean and still test good leave it alone is my motto.

 

I don't know if it is SCA I or not. The bottle doesn't say. It DOES say " Rust and scale inhibitor, keeps cooling system clean, protects metal, Reduces cavitation erosion-corrosion, will not affect gaskets hoses, contains Alkali. Where do you get test strips? They are probably the same as I use on my swimming pool to check PH.

 

since the label says reduces cavitation, it is the SCA

 

http://www.dieselpage.com/motorfw16.htm

or

Go to IH ask for the Fleetguard 3-WAY Coolant Test Strips CC2602B contains 1 Test strip.

They show A/F freeze point (EG and PG coolants), Nitrite level and Molybdate levels.

After looking for a while I did find NAPAKool 4056

Product name-----------------NAPA Kool : 4055, 4056, 4057, 4058
Trade name & synonyms--------NAPA Kool Coolant additive
Chemical name & synonyms-----Nitrite-nitrate-borate, sodium hydroxide
corrosion inhibitor

Although I did not find any specs on the product, I did find a MSDS (Material Safety Data Sheet that indicated the chemical makeup listed above.

This is a DCA2 formulation that is related to the PenCool family of SCA's with a Borate/Nitrate chemistry. The borate buffer can be hard on water pump seals.

DCA4 is a Phosphate/Nitrate/Molybdate chemistry that is less toxic than the DCA2 formulation. It also offers improved solder and aluminum protection, improved cavitaion protection, improved tolerance to SCA over and undertreatment and contains reduced solids which is better for water pump seals. The posphate buffers are what make the DCA4 easier on water pump seals. As an extra benifit the DCA4 formulation is less likely to cause silicate gells to form in the cooling system. Silicates are added to antifreeze to protect aluminum parts in car cooling systems. Since there are no aluminum parts in our diesel engines cooling system, you should be running a low silicate antifreeze.

The only other thing I could not find was a NAPA part number for less than 50 test strips in a pack. That number is FIL4107 for 50 strips and has a 23.59 price listed.