I bought a jug of Dex cool years ago and it's still sealed/unopened. Time for a coolant change and wondering if it's ok to use it or just discard it, eat the loss and buy a new one

 

I would think if it is unopened that it should be fine. It is the oxygen in the air that causes it to "go bad"

 

At $15.00, for all the trouble that stuff can/has caused over the years, I wouldn't risk using it. Just buy a new jug, or better yet, drain and refill the entire system with fresh Dex.


Your $$$ though.

 

Dexcool caused a lot of damage to plastic cooling system components in my '03 Land Rover-dissolved parts made of glass-filled nylon-eating away the nylon,but leaving the glass fibers intact. Not sure about P.O.s maintenance habits...

 

Had not changed it in my 2000 Silverado for 15 years and when I changed it,it looked like the new stuff I put in.

 

Lasts fine in a motor with sealing parts made for it.

A SBC OTOH... no. I tried it once. Every one of the paper gaskets - back of the WP, intake, WP, etc. - acquired a patina of pink fuzz building up on it. It goes right through typical paper gaskets, hardly even slows down.

Other than that, it was fine.

My experience in newer motors, with rubber seals and O-rings instead of paper gaskets, is much like 73's. All my newer cars, and my wife's and my children's and my children-in-law's, are filled with it. It's pretty damn durable. At least as much so as green juice.

 

Thanks everyone. The car in question came with it from the factory and has low miles. Some encouraging feedback. I think it's still safest to go ahead and buy a new jug anyway.

 

I'd use it. Probably has a long shelf life. Still better than the fluid that's already in the engine.

 

I just put a new radiator in my 2000 RamAir T/A this past weekend due to a small leak at the tank.I owned the car since new, 133K well maintained miles.
The Dexcool that was drained looked like brand new.
But....that's the stuff that's required for that engine.

I always preferred the green Prestone in all the 3rd gens.
Just my thought though.

 

I would toss it and clean the system and replace with something better seen nothing but problems with dexcool

 

I wouldn't put it in an older vehicle due to what someone mentioned earlier in the thread about older/paper gaskets. If you put it in a newer car that was meant to have dexcool then just check out some of it first. I had some really old, regular, sealed, unused antifreeze (might have been pre-mixed 50/50) that had turned to clumps like bad milk.

 

Prestone any color yellow has always been good to me. I have cleaned endless amount of crap out of motors when I had to replace gaskets that dexcool destroyed.

 

As everyone else already said, don't do it. Mechanics and DIY guys alike call that stuff death-cool for a reason. And our cars don't even specify it as the recommended coolant. Third gens are from back in the day when you could just put universal green coolant in everything.