How quickly does gelling happen?

[Speeddymon]

Hello, new member here, you guys come highly recommended. I apologize in advance for the long story.

TL;DR: How long does it take for coolants that can't be mixed to start turning into gel?

Full story: I had a friend of mine (who has worked on cars as a hobbyist since he and I were kids) change the thermostat on my mom's 2017 Jeep Wrangler around 7 months ago.

Well, I discovered today that he may have possibly used the 5 year yellow coolant from Valvoline (Zerex 05 something) instead of the Mopar 10 year pink/red coolant you're supposed to use.

The engine has not (yet) shown *any* signs of issues but she noticed her radiator fan working harder the past week or so and I found her reservoir was low. It's also super hot right now in SE Texas, so I wanted to find out what gives. I did my research and read about the danger of mixing coolants, so I called my "friend", and asked if he was aware of the mixing causing problems... Now I'm mortified to find out he possibly did this without doing his research...

So, I know we need to go get a coolant flush to be on the safe side; that's scheduled for tomorrow and there won't be any driving it until that's done. But I'm actually a bit surprised she hasn't had any overheating yet, so I thought I would come here to ask... How long does it take for gelling to happen? Even an anecdotal answer would be helpful at this point.

Also, can the engine be saved by just simply doing a professional flush? She's supposed to go to Pep Boys to get it done (they're the only shop that isn't far away, or else we would go to the dealer for this... And yes, lesson learned)

I used to be able to work on cars but it's been 20 years now since I did anything more than change the oil and these newer vehicles have some differences which is why I tend to leave it to people who do it every day...

Anyway, thanks in advance for your wisdom.

 

[CharBaby]

When changing the T-Stat 7 months ago, did your friend only "top off" the radiator with the Zerex or do a complete exchange of coolant? If he only topped off, that's not anything to worry about!

I don't believe that there has been any damage done to the Jeep due to the possibility of the wrong coolant. The 5 year coolant may just not be as robust as the 10 year coolant and may be a slightly different chemistry however, the coolant may need to be changed in the next 4 yrs/5 mo. But, I could be wrong!

I think that the fan is working hard(er) is due to it being extra hot there in SE Texas. Nor do I believe that due to not being the "exact" coolant according to Jeep, that there is any cause to have the system flushed. Maybe a couple of drain & refills with the coolant spec'd by Jeep will make you sleep better but I don't think there is any damage waiting to happen.

And personally(this is just me), I wouldn't let PepBoys touch my lawnmower let alone my Jeep.

 

[Speeddymon]

It was a partial drain and fill (but way more than a top off) because he initially removed the hose from the side of the engine where the thermostat isn't, so he ended up having to use more than he initially planned to.

 

[Nukeman7]

If the Jeep's OEM coolant was pink and not purple, it is Mopar's HOAT coolant. Zerex G05 is also a HOAT coolant (but silicate free) so it is not incompatible. While the chemical composition may not be identical and the dyes are different, I don't think it will cause any adverse reaction.

Zerex G05 is an approved formulation that meets Chrysler's MS 9769 specification for Mopar's pink coolant., so you are good.

G05 Spec Sheet

 

[dumkid]

I've mixed pink dodge coolant and zerex g05 a few times without issues. If you mix dex cool and old green coolant it'll form gel within a few hours (i mixed them in my waste coolant jug once)

 

[Plawan]

Nukeman7 is correct. It s compatible and you would be fine to leave the G05 in.