Violated owners manual recommendation... help.

[j_mac]

I have a '99 Mustang GT. I began using Prestone All Makes All Models a few years ago. I've only recently discovered BITOG's antifreeze section here, so I was dumb. Just the other day I had a bad pressure cap let go and dump most of the fluid on a long trip. Had to fill with tap water to get home. I then refilled with Prestone AM,AM mix.
I never had an owners manual for this car as I bought it used in 2006. So just yesterday I looked up an owners manual on the internet and I found out that in '99 Ford recommeded their "green" antifreeze. And they specifically recommend against using any orange or "DexCool."
Now, from this forum I understant the Prestone AM,AM is a "DexClone." !!

....SO, what have I got myself into? The owners manual recommends against DexCool types, but by switching over completely have I eliminated compatibility issues...
Or, have I step up myself where the DexClone will eat my engine and cooling system from the inside out?

 

[Audi Junkie]

Classic high silicate like olde Prestone "HD" or VW G-11 should not be mixed with any HOAT or OAT coolants, they are incompatible. OAT and HOAT are compatible. I am not afraid of mixing because I know what is compatible and what is not.

 

[Steve S]

Since you told all of us. Drain it out, is there a block drain and if it works drain it, other wise drain and flush with tap water when it looks clean then flush with distilled water. Finally add the proper coolant and you are good to go. It might be time to think about a new Ford or equal quality thermostat and rad hoses? just a thought.

 

[Panzerman]

Just get one of those Prestone flush kits, follow the directions with the water hose, flush it, refill with the correct Green coolant and it will be fine. Remember some water stays in the system from the flush, so you may want to mix it a little rich. Really cars are much more durable then you most give them credit for. If it makes you feel any better, I wrecked a company truck once( a Ford) and it said not to use the orange only Green on the resevoir tank, and the repair shop put in the orange anyhow. the company does not care about stuff like that, so telling them, they look at you like a freak. I drove it 50,000 more miles and it was still running when they traded it. Didnt hurt anything.

 

[rslifkin]

Flush it out, and refill with either old style green, or G-05, and distilled water. The key to getting 50/50 in the system after a flush is to add 1/2 the system capacity of concentrate, then top off with water. It'll mix once the engine is running.

 

[chubbs1]

Do a flush when you can. And use the recommended stuff or just about anything that is the same.

 

[exranger06]

Originally Posted By: Audi Junkie
Classic high silicate like olde Prestone "HD" or VW G-11 should not be mixed with any HOAT or OAT coolants, they are incompatible. OAT and HOAT are compatible. I am not afraid of mixing because I know what is compatible and what is not.


FWIW, on a bottle of G-05 (HOAT) there is a warning saying it is INcompatible with OAT coolants.

 

[j_mac]

I have access to some free green antifreeze. Looks like the old green stuff from the 1980's (not the dark green Honda stuff or whatever else.)
Ford recommends their "green" Motorcraft antifreeze in this car. Would the free green stuff I'm talking about likely be the same spec as what ford calls their "green" Motorcraft antifreeze.

I'm not sure of the origin of this antifreeze as it is a bulk product, but it is the old fashioned kryptonite green color. Its comming from the company my friend owns (a heavy equipment company.) I told him about my plight and he said "just get you some of the stuff we keep out back. Its the old green stuff."

 

[rslifkin]

Should be pretty much the same. The original coolant in your 99 is old school green.

 

[Al]

Drain it refil with Mixture of the green/distilled water. Do it again in a couple of days. Its not instantly gonna destroy the car..even if it is a Ford.

 

[j_mac]

But the problem is that I've been running the Prestone All Makes All Models in it for a long time. Its now probably almost pure AM AM (50% water of course.) The mix I drained from it looked a little dirty. Maybe sorta "blackened" which leads me to believe that the Dexclone has indeed been eating away at something plastic or rubber in the system. I've been slowly adding AM AM over the 4 years I've owned the car. God knows what was in it when I got it. And to top it all off I'm trying to determine if I have a leak somewhere. I think I do, but Its gonna take awhile between heat cycles and watching the coolant level for awhile to see if its steadily dropping. Wonder if there's already been irreversible damage? Wonder what could be "eaten up" by the dexclone in these engines? They do have a platic intake with water crossover. Hope its not being eaten.

Any thoughts would be much appreciated.