Switching Over From IAT to OAT Coolant in 2001 Dodge Ram?

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G-05 or Prestone Cor-Guard, which is an American take on Japanese pHOAT.

The silicate component in G-05 provides quick protection against cavitation of the cylinder liners, same with the phosphate in Cor-Guard. It takes a while for OAT to passivate metal. There’s reason why Mercedes and BMW are still using SiHOAT to this day - and Mercedes has a time-release silicate pack in their coolant tanks.
 
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I'm NOT buying into Prestones claims. I think it's all marketing and numbers. I might believe if it wasn't a Universal coolant.
Ford uses Prestone Cor-Guard as OE fill now - as Motorcraft Yellow. If Toyota says their pink coolant is good for 10 years/150K from the factory and VAG(VW/Audi mostly) their coolant is good for “life”, barring any cooling system parts replacement, I believe it.

There’s one poster here that hasn’t posted in a while saying he never had to change Dex-Cool on a fleet of vans he manages - only if there was a cooling system parts replacement.
 
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I'm NOT buying into Prestones claims. I think it's all marketing and numbers. I might believe if it wasn't a Universal coolant.

I'm not advocating mixing it with any other coolant as they claim is acceptable, but I have a hard time seeing a reason it wouldn't work in any system if there was a full flush/fill with the Prestone.
 
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Starting with an all compatible universal coolant means if you are stuck somewhere, you can add any coolant to continue on your way. I haven't seen corrosion in a cooling system that has received minimal maintenance in the last 30 years.
 
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I haven’t seen anyone complaining of issues with the Mopar OAT, but my Mopar interactions have been mostly limited to the LX car forums.

Even still, hard to imagine the coolant itself causing clogs in the system while still within its service life. Once it’s outside its service life, sure, or if it were mixed with really hard water during fill, but the factory fill OAT is mixed with distilled water and shouldn’t be causing any problems.
Oh the 10 year OAT has been plenty problematic with heater core stuff. Journeys, rams, GC, 200s.
 
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Oh the 10 year OAT has been plenty problematic with heater core stuff. Journeys, rams, GC, 200s.
That’s the reason why Ford switched all their Dex-Cool stuff to Prestone Cor-Guard. There was a TSB stating to do any repairs needed including an updated heater core then a flush and fill with Cor-Guard before Ford switched gears and used it for everything that took orange.

VW’s G-12/13 series of coolants were also close to Dex-Cool but it only used 2-EHA alone - no benzoate/sebacate/adipate. I wonder what Mopar’s new purple/pink OAT is using.
 
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That’s the reason why Ford switched all their Dex-Cool stuff to Prestone Cor-Guard. There was a TSB stating to do any repairs needed including an updated heater core then a flush and fill with Cor-Guard before Ford switched gears and used it for everything that took orange.

VW’s G-12/13 series of coolants were also close to Dex-Cool but it only used 2-EHA alone - no benzoate/sebacate/adipate. I wonder what Mopar’s new purple/pink OAT is using.
the original g12 and basf g30 g33 and g34 (gm europe dexcool) were all sebacate only formulas

mopar 10yr is just old Paraflu UP dyed purple to not confuse techs. all NAP free coolant are functionally identical and prestone dexcool advertises 2013+ chrysler for the same reason
 
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I've read about Chrysler putting some sort of slow release silica packets in the reservoir tanks on the vehicles with the purple OAT coolant. Is that something I would want to do with this old truck when putting it together you think?
That’s more a Mercedes move than a Mopar one. Mercedes also switched to G-48 in the mid-2000s and then to purple G-40 in the late 2010s.
 
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