Coolant change

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expressreg

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i have a 2017 Ram 1500 5.7 RcSb and i want to change the coolant but i cant find any info of what it takes other than Mopar OAT (MS-90032), and i cant seem to find that anywhere. i wanted to know whats the next best thing you can buy at stores?
 

EdGs

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^^^^^This^^^^^

68163848AB or AC (concentrate)
68163849AB or AC (50/50 pre-mixed)

But, In my local area, the dealers "don't stock" the OAT concentrate. They can then charge you ~$30 each for 4 gallons of pre-mixed coolant.

DO NOT MIX ANY OTHER COOLANT WITH YOUR RAM COOLANT

There are aftermarket types that will work, but it's not worth risking your engine if you get the wrong one.

This is the OAT concentrate you need:


For a complete drain and fill, you will need 2 gallons of concentrate. Also buy 2 gallons of Distilled water from your local grocery store, and mix 50/50. That will give you 4 gallons of the proper 50/50 mix.

If you only drain the coolant at the radiator you will only get less than half the old coolant out.
 
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EdGs

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Some drain at the radiator, fill with distilled water, run to temp, drain at radiator, fill with distilled water,..........

Until the radiator drains clear. Then refill with concentrate only.

When I did my cam and lifter job, I removed the block drains as well, removed the heater hoses, and removed the grille and emptied and rinsed the coolant reservoir.

All said and done, it took just shy of 4 gallons of 50/50 to fill it.
 

RamChief30

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Do a complete flush and get rid of the MOPAR unicorn P*ss. ;)
What do you recommend instead of the MOPAR factory fluid (or P*ss)? I live in the desert and definitely need to use the best stuff.
 

Pushrod8Speed

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I found this a while back (1st link) and a second link with coolant info. I used the Peak (NAP5D) because it' was easy to find and don't like when manufacturers try to trap you into their stuff. But the spec is what's important.
 

Burla

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What do you recommend instead of the MOPAR factory fluid (or P*ss)? I live in the desert and definitely need to use the best stuff.
Mopar oat is great coolant, read here. In the dessert you may want to run some RMI25 if you feel like adding a leave in cleaner, read up on it. Or if you truck is running hot a different thermostat and/or some water wetter. The base of every coolant that is beneficial for your vehicle is etholyene glycol. So many different ones out there such as Asians and dex clone, which you don't want. The Chrysler is mostly straight ethylene glycol like peak global life. So either use Mopar which is great coolant, or Mopar recommended coolant usually comes in purple jug or lifetime coolant that is straight ethylene glycol, period stop.
 

caulk04

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Weird to see this today. I just changed mine yesterday. Simple drain and fill, light flush through the heater core.

Zerex 'American' is what went in mine, along with the remainder of a bottle of Mopar 50/50. Mopar was orange/pink, Zerex more orange. Meets spec, ain't worried.

FWIW - Same coolant has been in the wife's '19 Fusion for over a year.
 

Burla

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Weird to see this today. I just changed mine yesterday. Simple drain and fill, light flush through the heater core.

Zerex 'American' is what went in mine, along with the remainder of a bottle of Mopar 50/50. Mopar was orange/pink, Zerex more orange. Meets spec, ain't worried.

FWIW - Same coolant has been in the wife's '19 Fusion for over a year.
Just so you know you did put dex cool in there. "They" say dex clones are ok but they also say non dex coolants are spec'd, if you can chose between the two, I'd opt for non dex cool, no 2eha.

2-Ethylhexanoic Acid (2-EHA) is a common, cost-effective corrosion inhibitor used in many Organic Acid Technology (OAT) coolants, including Dex-Cool clones. While it effectively protects aluminum, it is controversial because it can act as a plasticizer, potentially softening or degrading silicone-based gaskets and plastics
 

Burla

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I see they say "American" for both dex clone and non dex clone, as if they can make it more confusing. If the container was orange = dex clone, if it is purple Mopar clone.

8dcb-f6f0055c4c5d.d75732b1f481fb6721eebf18e1ba1c0e.jpg
 

caulk04

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I didn't use Prestone.

Zerex does also list a dexcool variant that looks about the same as the 'American Vehicle' stuff I have. Both stating OAT and listing ethylene glycol and EHA. End of the day, it's compatible and not that serious IMO.

Screenshot_20260511-185813.png
 

Burla

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Compatibility isn't the issue, it is what happens to cooling systems with 2eha in them= potentially. It is a risk that most people would suggest is unnecessary. just posted it for info, all dex clones are orange jugged, use it or don't use it is an option. If you ever see any signs of slime, add RMI-25 and check overflow tank in 500 miles. Peace

Dex-Cool (orange antifreeze) is designed for sealed cooling systems; when exposed to air (air entrainment), it can react to form a thick, brown sludge or mud. This reaction, often caused by a leaking radiator cap or failing hose, causes the coolant to break down and can lead to severe corrosion, overheating, and damaged seals

Now Mopar coolant does not have this issue in the same ilk, only dex is that severe.
 
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