between Gooch and Stewart on Ford-trucks.com...
It's just my opinion, but since Ford didn't make the engines, I go by what International recommends, since they made the engines for Ford.
International recommends an Organic Acid Technology (OAT) Heavy Duty Extended Life Coolant (ELC) for the L99 and up 7.3's, but Ford doesn't.
Ford recommends their "gold" (Zerex G-05 equivalent) Hybrid-Organic Acid Technology (H-OAT) coolant starting with the '02 model year 7.3's.
After much research, International discovered an OAT based coolant doesn't work well and has compatibility issues with the older injector cup material, sensors, front cover, seals, gaskets, o-rings, and other stuff, like certain head gaskets that have silicone sealing rings for the coolant flow holes. To be certain, the problems found with the older type of sealant used during injector cup installation, which doesn't mix well with an OAT ELC, is enough to stop someone in their tracks.
Coolants like ELC's (usually Red) and G-05 (usually Gold) will have these OAT's. Conventional coolants (usually Green) will not.
So, with these incompatibility issues, International revised the necessary components on all 2/2/99-up build engines (SN 940614-up), and began recommending and factory filling with HD ELC coolants mid-year 2000.
GM's Dexcool is an Organic Acid Technology (OAT) coolant, but not all OAT coolants are like what GM uses.
GM typically uses a forumulation which is specifically not recommended for your diesel engine. Dexcool type coolants were absolutely never intended to be used for diesel applications.
There are many modern Heavy Duty Extended Life Coolants specifically designed for diesels. Delo ELC, Rotella ELC, International's Fleetrite ELC, CAT ELC, Mobil 1 ELC, and a host of others.
Compared to conventional "green" coolants, ELC's will address diesel cavitatation protection and provide superior metal corrosion protection, provide better heat transfer, require no testing and maintenance, be free of harmful abrasive silicates, borates, and phosphates, and have an operating life up to 1 million miles (Delo ELC).
Ford's "Gold" (G-05) coolant is nothing like a Heavy Duty ELC coolant, and it will not meet the strict specs required of a HD ELC coolant, or provide the higher level of protection.
The "Gold" is simply a universal hybrid, one-size-fits-all coolant that Ford uses in its entire line up that, with the exception of the Powerstroke, are all gasoline engines. Ford simply uses the "Gold" in the 7.3L PSD out of convenience, simplicity, cost, and uniformity throughout it's product line and dealerships.
The "Gold" coolant contains conventional "green" coolant components, like silicates, which eventually form microscopic abrasives that eat water pump seals. The "Gold" provides a lower level of cavitation protection using traditional SCA's like nitrite, it has a shorter life, it's not as effective as an ELC at heat transfer, and in some applications, requires testing and SCA maintenance (just like the conventional "green" coolant) if you are an enthusiast about protecting your engine.
In fact, Ford recommends you add SCA's to the "Gold" in certain F-Series applications. Caterpillar and John Deere also recommend adding SCA if it is going to be used in their diesels.
Ford's H-OAT "Gold" coolant will not meet International's heavy duty diesel B-1 specification. A Heavy Duty ELC will.
The "Gold" will work, but it's not the best.
so there you go
"After much research, International discovered an OAT based coolant doesn't work well and has compatibility issues with the older injector cup material, sensors, front cover, seals, gaskets, o-rings, and other stuff, like certain head gaskets that have silicone sealing rings for the coolant flow holes. To be certain, the problems found with the older type of sealant used during injector cup installation, which doesn't mix well with an OAT ELC, is enough to stop someone in their tracks."
it's not JUST cup sealant, although that's where it shows up first usually, probably with the extreme heat to catalyze things faster
-'97 F250HD 4x4 7.3-
-'99 Cobra 426w-
-'76 LS408 Stingray-
-'93 302 Camaro on the juice-
Last edited by narmalee; 11-21-2017 at 05:43 PM.