Spring coolant top up

[F4U-1A]

So I have a lot of 5yr Chrysler orange HOAT 50/50 left over from my Jeep JK. Would I have an issue adding to the current coolant in the Chevy Prestone long life yellow stuff HOAT? I know it will gel with the purple OAT in my Subaru.

 

[someotherguy]

Can't comment on mixing the coolant types, but I'd try to figure out where the coolant is going. Shouldn't need a top-up.

Richard

 

[1998_K1500_Sub]

So I have a lot of 5yr Chrysler orange HOAT 50/50 left over from my Jeep JK. Would I have an issue adding to the current coolant in the Chevy Prestone long life yellow stuff HOAT? I know it will gel with the purple OAT in my Subaru.

Find out the chemistry involved and see if they're the same.

Not all "OAT" / "HOAT" chemistries are identical, AFAIK.

Prestone has been known to say "mixes with all types".

Personally, I wouldn't mix. I never do.

Engines == expensive
Antifreeze == cheap


Very interesting reading may be found in these Motor Magazine stories about coolant types and their additive packages, and how / why they vary from manufacturer to manufacturer and application to application:

Coolant Confusion: It's Not Easy Being Green ... or Yellow or Orange or ...​

https://www.motor.com//magazine/pdfs/082004_04.pdf


Relearning the Alphabet: Making Sense of the Cooling System Scene
https://www.motor.com/magazinepdfs/082010_08.pdf

Both these should be required reading for any shade tree mechanic, IMHO.

 

[F4U-1A]

Can't comment on mixing the coolant types, but I'd try to figure out where the coolant is going. Shouldn't need a top-up.

Richard

Yes it does, has being doing it every winter since I drove it off the lot new in 1996, sublimation at -35C here in our outstanding Canadian winters. Good Times

 

[F4U-1A]

Update after endless tech research, I have OAT in my Chevy since new. Orange 1, the JK is Orange 2 HOAT> And that will F up the system like my Home Brew brain again today. All Good

 

[someotherguy]

Yes it does, has being doing it every winter since I drove it off the lot new in 1996, sublimation at -35C here in our outstanding Canadian winters. Good Times

Have never heard of this being an issue, but I also don't live in subzero-land. Single digits on the very rare occasion is enough for me to say.. NOPE

Richard

 

[Sean Buick 76]

I’ve lived in -35 winters for 20 years, owned 30+ vehicles and I’ve NEVER had to top up the coolant. It’s leaking or sucking it into the cylinders.

 

[Caman96]

Might be time to call Blackstone Labs.

 

[RichLo]

I have have noticed that I need to top off coolant on multiple vehicles every fall when I run specific gravity test to make sure they are all still good to -40 or better.

I never thought about it because they are all between 20-90 years old. None of them leak or show signs of burning, I just figured seepage somewhere. My daily driver 2014 Cruze with 200k+ on it needs to be topped off periodically too.

Not sure if there is something to do with the extreme cold shrinking or hardening rubber causing seepage or if its actually somehow causing evaporation but it can be a thing.

 

[F4U-1A]

I’ve lived in -35 winters for 20 years and I’ve never had to top up the coolant. It’s leaking or sucking it into the intake.

Good to know my JK does not loose coolant in the last 14 years since new. Must be that 5.7 Vortec assembled in Fort Wayne Indiana ?