G48 Green or Blue?

[Regaman]

As simple of a question as it sounds, this one has me stumped.
I'm currently rebuilding my E36 M50 motor out of my '94 325i. I picked up two gallons of coolant to refill the system with. (I already had half a gallon at home)
Here's where it gets weird: All three of these coolant containers are Zerex G48 50/50 coolant. All three containers appear to be the same. And yet, one of these three containers has green coolant instead of blue. I can't find any difference on the bottles between the green and blue.
If both of these containers are supposedly the exact same stuff then why is one green and the other blue? What's the difference? I know you typically can't mix coolant but can you mix these if they're the same stuff? I have more blue than green, but when I started refilling the system I used the green first. (I didn't even realize they were different colors until my coolant came out of the bottle green, to my surprise.) If I want to use blue instead do I need to do a full flush to clean out the half gallon of green I've put in so far?

[MarcoZandrini]

Contact Zerex via the company’s customer service phone number. Are the Zerex part numbers on the containers the same?

[pbonsalb]

G48 is fine. Color makes no difference. I’d buy blue just so anyone who works on the car knows it’s different from nurnsl green. Zerex GO5 is also fine to use in BMWs.

[bmwdirtracer]

We have G48 at our shop, for BMW's and MB's. It is blue, every time. Even the label is blue. If I found green coolant in a G48 bottle, I would return it.

[shadowpuck]

yeah - very strange. is the UPC/barcode/part number the same on all the bottles here?

[Shoe Coupe]

yeah - very strange. is the UPC/barcode/part number the same on all the bottles here?

ran into this today. i used g48 in 2018, and it was blue. i open a new container to put into my e46 m3 today and it was bright neon green. I called valvoline and they said they changed the die.

But why would they do that?