ATTENTION: Know Your Jeep JK Wrangler Coolants and Save Your Engine!

WJCO

Meme King
My thermostat housing blew over the weekend, I pulled over to a gas station and my coolant tank was empty. I poured in some Peak coolant/antifreeze and limped it home. Mechanic said water pump is leaking now (probably from it overheating after the housing bursted). I’m tying to figure out what caused this...did I use the wrong coolant?

Previous to this, I was topping off with Prestone every once in a while. I figured some fluid probably leaked out while wheeling.

So now in my tank I have a mix of Mopar, Prestone and Peak. Any idea if these mix?

How hot did it get? Did gauge go to red? Any lights illuminate on dash?
 

brah

New member
Gauge got to full red. Lightning bolt light and CEL came on but have since turned off. By the time I toggled through the onboard computer, temp was at 230, but this was after it was parked. Mechanic turned on the car to pull it into the shop and I noticed a couple plumes of white smoke come out the tail pipe (this was the first time it was turned on since it overheated), not sure if that is typical on a cold start (outside air temp was 80, mid humidity). After they replaced the housing, I noticed no more white smoke out the tail pipe.


Should mention this is a 2014 wrangler
 
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Ruddee

New member
Thanks for the info

Service Tech at dealership here didn't know there was a difference....that's in West Texas...
 

VScott

New member
Part number

You list a different part number for the OAT than what’s on the TSB. Yours is 68163848AA and the TSB 68163849AA
 

MericaMade

Active Member
This was really good information and I thank you for taking the time to write this up. It might have been answered and sorry If I am asking again, but is there a Preston or Peak Antifreeze/ Coolant that is compatible with the OEM OTA?
 
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Mike11C

New member
Prestone is good

This was really good information and I thank you for taking the time to write this up. It might have been answered and sorry If I am asking again, but is there a Preston or Peak Antifreeze/ Coolant that is compatible with the OEM OTA?

A couple of days ago, I added about 8 ounces of Prestone to my 2015 Wrangler. Yesterday, I stumbled into this thread. *GASP* I immediately started searching for info online but, there was way too much conflicting info. One site says you're going to ruin your engine unless you flush it out and refill with Mopar OAT antifreeze while others say, it's fine, just look at the jug, it says "mixes with all colors" and "won't void your warranty". Well, I emailed Prestone and asked them directly. This was their response:

Good Morning Michael,

*The Prestone Antifreeze/Coolant in the yellow jug is an OAT formulation that is fully compatible with the factoy fluid in your Jeep.* They are both ethylene glycol based.* There is no need whatsoever to drain the system.* Please let me know if you require anything further.

*Sincerely,

*Aaron Jones

Prestone Consumer Relations Representative

Phone: 203-731-8191
 

sipafz

Caught the Bug
A couple of days ago, I added about 8 ounces of Prestone to my 2015 Wrangler. Yesterday, I stumbled into this thread. *GASP* I immediately started searching for info online but, there was way too much conflicting info. One site says you're going to ruin your engine unless you flush it out and refill with Mopar OAT antifreeze while others say, it's fine, just look at the jug, it says "mixes with all colors" and "won't void your warranty". Well, I emailed Prestone and asked them directly. This was their response:

Good Morning Michael,

*The Prestone Antifreeze/Coolant in the yellow jug is an OAT formulation that is fully compatible with the factoy fluid in your Jeep.* They are both ethylene glycol based.* There is no need whatsoever to drain the system.* Please let me know if you require anything further.

*Sincerely,

*Aaron Jones

Prestone Consumer Relations Representative

Phone: 203-731-8191

I would keep an eye on it! It’s not like Aaron’s going to help you out if it does gel up.
 

TrailHunter

Hooked
Bump..

I never thought Coolant would be so confusing.... I noticed my coolant is a little below the MIN mark on the reservoir and I would like to top it off and have some extra on hand.... Can I not buy something from A local Napa, Autozone etc..? Is the "OAT" only sold at dealerships? Is MOPAR the only one that makes coolant for JK's?

Edit: Just saw this:

It's only when you mix HOAT and OAT that causes the gelling to occur. The universal Prestone won't cause a problem.

--
Build Thread - Adventures of Fiona - https://wayalife.com/showthread.php?t=47407

^^^So Prestone is fine then?
 
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BaddestCross

Active Member
Bump..

I never thought Coolant would be so confusing.... I noticed my coolant is a little below the MIN mark on the reservoir and I would like to top it off and have some extra on hand.... Can I not buy something from A local Napa, Autozone etc..? Is the "OAT" only sold at dealerships? Is MOPAR the only one that makes coolant for JK's?
O'Reilly's sells it, but you can use the universal green shit with no problem. Just don't mix the HOAT and OAT.

--
Build Thread - Adventures of Fiona - https://wayalife.com/showthread.php?t=47407
 

naysjp

Member
I topped off the coolant reservoir 2 days ago after 4 yrs of owning Blanca and she still runs so I must have gotten the right coolant. LOL. I admit it was scary making sure I got OAT for the 14'
 

Wild Hare

New member
Very confused. So here y'all say a 2015 Wrangler should use OAT but when I go online to Advanceautoparts, the "exact fit" is HOAT. Is there a way to know what's there now? Other than color since I'm color blind. I don't know that's it's ever been topped off. I have not had to do it yet.
 

CharlesC

Member
Best bet is to go to your dealer and run your Vin#. It will tell you exactly what you need[emoji106] * That will tell you what it started with at least.


Sent from my iPhone using WAYALIFE mobile app
 
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BeRoyalKC

New member
I've read through the entirety of the thread and now I'm probably a little over paranoid (bought the 2013 JKU in June w/62k miles...who knows if it's been topped off, etc). It has a manufacture date of Jan 2013 so I *should be* beyond the confusion of whether Chrysler made the change by model year or actual year.

Anyways, I need to replace the coolant thermostat (P0128) and just happened to find this thread. Obviously my owners manual calls for OAT and I pulled some out to check color but wanted to get a few extra eyes on it to be sure. Obviously looks orange as hell inside the radiator. When I pulled it out it definitely looks like it's got a purple hue (albeit slight) unless you shine light directly at it. Am I seeing that right? I tried to get photos at a bunch of different angles since it sounds like it's a light refraction issue. Thanks all! IMG_20190112_094057.jpg IMG_20190112_093902.jpg IMG_20190112_094233.jpg IMG_20190112_094224.jpg

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MSJKU11

Caught the Bug
I've read through the entirety of the thread and now I'm probably a little over paranoid (bought the 2013 JKU in June w/62k miles...who knows if it's been topped off, etc). It has a manufacture date of Jan 2013 so I *should be* beyond the confusion of whether Chrysler made the change by model year or actual year.

Anyways, I need to replace the coolant thermostat (P0128) and just happened to find this thread. Obviously my owners manual calls for OAT and I pulled some out to check color but wanted to get a few extra eyes on it to be sure. Obviously looks orange as hell inside the radiator. When I pulled it out it definitely looks like it's got a purple hue unless you shine light directly at it. Am I seeing that right? I tried to get photos at a bunch of different angles since it sounds like it's a light refraction issue. Thanks all! View attachment 318894 View attachment 318895 View attachment 318896 View attachment 318897

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Did you try to shine a light through the reservoir to see if it looks purple? If you take it out I think it has the orange color due to the light. I would think you're fine since mixing them causes it to solidify and you would probably notice performance issues.

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BeRoyalKC

New member
Did you try to shine a light through the reservoir to see if it looks purple? If you take it out I think it has the orange color due to the light. I would think you're fine since mixing them causes it to solidify and you would probably notice performance issues.

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I didn't take the reservoir out and shine a light through it, but I'll do that next. My issue is when I replace the coolant thermostat I'll need to top the coolant off and I want to be sure I'm using what's in there. I'm assuming it's OAT since that's what it should've come with from the factory and I haven't noticed any issues (it either hasn't been topped off or it has been with the correct stuff). Outside of color there's no way for me to know if it had previously been flushed and incorrectly filled with HOAT, though.

Might just have to consider a full flush to be completely sure.

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