Hi all. I have a 2012 Grand Caravan that I bought new.

This week, it started throwing a P0128, and I confirmed that the coolant temp isn't getting about maybe 160 degrees, so I'll need to change the thermostat, and this will require me to add some extra coolant.

I know it would have come with a factory HOAT fill. However, back in 2016-ish, I got upsold on a radiator flush at the local Mr Lube. At the time, I had no idea that there was a model year break in the coolant used, so I assumed it was refilled with HOAT.

However, now I'm not so sure anymore. The coolant in the overflow jug is very clean and bright orange - like a melted orange popsicle orange. I want to believe that it's a proper HOAT fill, but I would expect that to be yellow if it's coming aftermarket. I read somewhere that aftermarket Dexcool fills are often also Orange, which makes the think the kid who did the flush was as clueless as I at the time, and filled it with Dexcool.

So, my million dollar questions are such:

1. Is there a definitive way I can tell what kind of coolant is in there?
2. Is it common for Dexcool to be orange in an aftermarket fill?

Unfortunately, the paperwork that reflects that coolant flush disappeared when I moved a few years back.

I'd rather not pay for a full rad flush right now, but I need a solution, and I'd appreciate any thoughts!

Orange is the wrong color for Mopar fills of that vintage which run from pink to purple. You could do a complete drain followed with a couple flushes and the correct coolant from the dealer along with your repair.

Actually, the factory HOAT fill is supposed to be orange. I just don't know what the aftermarket fill is...

PEAK's orange coolant is their Dexcool-compatible OAT, as is Prestone's. As are a few other generics that I looked at are also orange.

I'm starting to think that the refill is definitely Dexcool - the person doing the flush probably saw the orange factory HOAT fill, and refilled with what they knew as orange (generic Dexcool).

Chrysler/Mopar G-05 HOAT did come as an Orange-ish tint AF from the factory. The dealer part for subsequent use was/is more red-ish in tint.

Unfortunately there's no way using color alone to know what's in there now. DexCool does have a "similar" tint to Mopar G-05, so you're going to have to decide how comfortable you are with not being certain. One of the best Mopar AF color posts is in the link. Scroll to Ivoryring post #47 to see pics of Mopar HOAT tint (left side).

https://www.wranglerforum.com/f274/2013-coolant-is-orange-pink-should-be-purple-297057-2.html

My 2015 Caravan is pink in color (it's never been changed).

Every OE coolant from 2012 to present in 3.6L pentastar engines I have personally seen, and I have seen a bunch, has been pink to purple in shade. The replacement from the dealer is also pink to purple in shade. Perhaps prior to the Pentastar with the 3.3/3,8 there was an orange antifreeze but it seems in my recollection they were also pink. I'm guessing that if it is orange than it has been contaminated or isn't Mopar OE coolant. While the cited Mopar color choices are interesting and does show an orange in the mix, I would be extremely wary and do the flush and add the Purple OE coolant as specified for that vehicle and eliminate the possibility of plugging the system with sludge.

All of the literature suggests that the new pink/purple coolant was introduced in the 2013 model year: http://www.wk2jeeps.com/tsb/tsb_wk2_0700412a.pdf

Depending on production date, his 2012 may or may not be considered a 2013.

Be careful on that engine to bleed the air out of coolant. If there is air still in it then you can overheat and ruin it.

All the Chrysler vehicles I've had in that era had ORANGE coolant which was G05 HOAT. All aftermarket Dexcool coolants I've ever used have also been orange. So short of expensive chemical analysis, I think you have a mystery on your hands.

How long have you been driving it with the questionable coolant? If there's no issues, I'd just schedule the next coolant service interval a bit early and keep a watchful eye on it. If you want extra piece of mind, coolant is cheap-- just do a thorough flush and put the correct G05 coolant in it.

Most people just grab a bottle of coolant off the shelf and put it in whatever they have in there already-- I'm certain that aftermarket Dexcool has been mixed with likely every possible coolant chemistry on the planet by now, and I don't hear of many horror stories resulting from it. I don't think anything awful is going to happen by leaving it in there, but personally it would bother me to have potentially mixed-up fluid.