Green 3 year anti-freeze only? 2000 GT

It seemed to be all I could buy, so that's what I got... in my '97 now... doesn't seem to be a problem.

Most likely the same reason 5 years ago they recommended not using synthetic oil. "Ford has not tested the effect or affability of that product on Ford automobiles." Translation, no one has paid us to recommend their product yet....

I can't tell you whether a specific "5-year" product would be a problem or not but Ford specifically recommends against some of the non-green long life products because they are incompatible with the gaskets and seals in some engines. For my vehicles I just use the Green stuff like came from the factory and don't have to worry about it.

There is a newish 5 year regular green antifreeze. I read the contents, didn't see anything special so I figured it wasn't. Label read that it could be used in anything practically and all stock of the previous formulation had been replaced with it.

replace it every year, if it gets contaminated or slightly conductive it will cause corrosion in radiator, water pump and elsewhere.

Doesn't that defeat the purpose of buying 5 year anti-freeze?

that is the point, it is just a "sales" gimmick number not based on fact.

Sorry I don't know where I read it but in one of the trade mags they did an article on all the various anti-freeze's on the market and the asked a Ford engineer about the need for changing regular antifreeze every 3 years and he basically said you could proabaly go 5, there wasn't any big research behind the stated interval. In a different issue they also talked with some Ford engineer about flushing brake systems and he said they had done research on that and unless you are in the habit of constantly opening up your master cylinder there is no reason to flush the system other then flushing it when you do a brake job. Reason why was that relatively early after a flush the brake fluid will absorb pretty much all the moisture it's ever gonna as long as it stays sealed. So if your purpose of flushing is to keep it moisture free you need to be flushing it every 6 months or so.

Something does indeed cause color changes in coolant and brake fluid. Then again it takes 2-3 years for that to occur. If either is getting dark and it's been a couple years and I am doing something with the system anyway, might as well take care of it.

So you are saying that the only difference between green and orange antifreeze is the color and what they tell you to do with it???

We aren't talking green and orange but new green vs. old green. There is 5 year green now.

and you should change it out every year.

So, what's the difference between them on the ingredient label?

I'd have to compare them side by side... the new stuff didn't have anything unusual in it by first glance