HOAT or OAT coolant?

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Sybil

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Dump the crappy water based coolant and use Evan's. It's the best period.
 

Mariuzzu

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Hi, I'm new to this fantastic forum and I've been looking for some info about the fluid to use and sorry for resume this old discussion...
I have a 2004 Ram 5.7 Hemi and I would like to replace the old antifreeze coolant, but also reading this discussion I am very undecided on the type to use: the red (HOAT) would be okay?

Thank you very much.

Sorry for my english...
 

Pull Ya

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remember that it takes 3 "at a boys" to equal 1 Oh ****! :naughty:
Jay
 

Leprechaun Lawns

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Okay I have read everything in this post and I'm still slightly confused I have a 2005 Ram with the 5.7 hemi which is the proper coolant I need to put in that truck
68163849AA or 68163848AA??

Thank you for your time
 

crash68

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Okay I have read everything in this post and I'm still slightly confused I have a 2005 Ram with the 5.7 hemi which is the proper coolant I need to put in that truck
68163849AA or 68163848AA??
Ram didn't start using OAT coolant till 2013, most likely your 2005 uses a HOAT coolant, DO NOT MIX the two types as it will gel up in your coolant system.
68048953AC is a Mopar par number for HOAT coolant.
Questions about your 2005 are better asked down in the 3rd Gen section: https://www.ramforum.com/forums/3rd-gen-ram-2002-2008.43/
 

EdGs

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^^^^^This^^^^^

Okay I have read everything in this post and I'm still slightly confused I have a 2005 Ram with the 5.7 hemi which is the proper coolant I need to put in that truck
68163849AA or 68163848AA??

Thank you for your time

Neither, those are both OAT coolants -3848 is concentrated, and -3849 is 50/50.

The other thing to consider is what has been used in this truck, incase someone else previously had it and changed it to something different.

Coolant is one thing where mixing different types can be bad.
 

Grams

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EdGs and crash68 both offer good, correct advice: If you don’t KNOW what is presently-installed, a complete fresh-water-flush and replacement will be Best.
Ram used HOAT thru the 2012 model-year, then switched to OAT.

READ YOUR OWNERS MANUAL to confirm what was original, and be certain to use the same. Do not chance that others may have used improper coolant mixtures.

My 2012 Ram 1500 definitely used HOAT and had a warning lable under the hood to that effect. However, my 2015 Ram 1500 Owner Manual specifies OAT, as does my 2024 Ram 2500.

It is my understanding that Chrysler products quit using HOAT in 2013.

Again, you may not know what previous users may have installed. Do not mix the different types, and be aware that “color” is not a fool-proof method of determining type. Some mfr’s do not conform to any standard of color.
 

crash68

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Do not mix the different types, and be aware that “color” is not a fool-proof method of determining type. Some mfr’s do not conform to any standard of color.
Both Ford and GM have OAT coolants that are orange which is the color of the Mopar HOAT coolant.
The Mopar purple OAT coolant likes to turn a orangish-rose color over time as well.
 

Daw14

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Okay I have read everything in this post and I'm still slightly confused I have a 2005 Ram with the 5.7 hemi which is the proper coolant I need to put in that truck
68163849AA or 68163848AA??

Thank you for your time
Both of those are OAT one is concentrated the other is Not

68048953ac is HOAT 5 year , 100,000 mile coolant

Use Rmi25 to flush your system.
 

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