Does coolant expire?
 

So the other thread on green coolant had me thinking. I bought a 55 gallon drum of fleet charge sca 50:50 in 2015. I think I only used 10 gallons of it, and it has been sitting since. So the question is... Does this stuff expire!?

Yes, in about another 30 years.

Depends on what the drum is made of. The anti-corrosives in the coolant are sacrificial and will react with a bare steel drum.

Bingo. Don’t add hard water, (minerals), to coolant mix, ever. Being diesel guys, coolant mix and PH takes on another level of importance but really, it’s important in any machine. :cool:

Pretty much. Where ever you have dissimilar metals the more active metal will sacrifice (corrode) as an anode.
This is why coolants have active metals.
To replenish the coolant active metals with just an additive find some "coolant rust inhibitor"

If the inside of his metal drum is still clean, (rust free), is he in the clear?

Wait...he did not say whether the drum was metal or plastic. OP?

It's a metal drum, more then likely is coated inside. I won't be able to physically look at it for a little bit now.

I bought it from an oil vendor, and is the original barrel with labels. No funny business.

My response was thinking you were worried about the coolant in your land shark. (lots of dissimilar metals.)

According to VW coolant does expire when it's sitting on a shelf but doesn't when it's in your cooling system.

That makes perfect sense. :rolleyes:

One of the big problems of the Ford 6.0L diesel motors from 2003-2007 was the coolant they used. The "Ford Gold" coolant would crystalize after a period of time which would block the tiny passages in the oil cooler, and EGR system. This would increase the pressure in the head which would blow the head gasket/stretch the head bolts, and ultimately wash down the cylinders with coolant.

It was highly recommended to change out the factory coolant, and completely flush the system to get rid of any crystalized traces before any problems were discovered. It was also good to replace the stock head bolts with head studs (which don't stretch), and the head gasket while apart. Many eliminate the EGR cooler, and change the oil cooler as a preventative. (Bulletproofing).

I have never worried much about my coolant aging out. I have had my El Camino 27 years. It came with a too small 2 core radiator that was taxed to the max on a normal hot day, in in really hot weather it would not keep up. I replaced it with a high quality 3 core, and never have overheating issues unless I sit at idle in really hot weather for longer than 10 minutes.

I change out my antifreeze every 24 months or so. I change it the fall. Plain old Prestone green fluid, cheap and available anywhere. After 20+ years and 300,000 miles the radiator has no corrosion, and looks great inside.