Good coolants for my vehicles?

[michaelc80]

I have 3 vehicles-2 Jeeps (96 and 00) with the 4.0 6, and a Nissan 300ZX non-turbo. I guess I've never thought much about coolants before, and simply put in whatever I had (or picked up from Wal-Mart). Every vehicle I've owned has had the green coolant in it. My question is-since I plan to flush/fill all 3 in the next couple of weeks anyway, what should I look for in a coolant? Is there a type that stands out that would work in all 3? Or should I look for a specific coolant for each type of engine? Is there a newer coolant technology that will help protect the engine(s) better, or will pretty much any coolant off the shelf work?

I never realized how little I knew until I came to this board!

 

[Matt_S]

Chrysler is now using G05 (Zerex makes a version) in its vehicles, so it should certainly be safe to switch the Jeeps to that. If you want to switch the Nissan as well, I would expect that you'd be safe. I would just caution you to flush out the regular coolant thoroughly, making use of any block drains if available.

That being said, there's nothing wrong with the old, reliable green antifreeze, as long as you keep it changed on schedule.

 

[Ray H]

Hee-hee-hee. "Old reliable green" is not only hopelessly obsolete in modern aluminum-intensive cooling systems, it's being discontinued. (I suspect it's at least partly an EPA thing to further restrict phosphate contaminants in the environment...) Prestone already has reformulated their "standard" antifreeze/coolant. What's being sold now in the familiar Prestone yellow jugs is the same as Prestone's own DEX-COOL, but dyed green instead of orange (and cheaper). And, like DEX-COOL, it's an extended life fluid. Don't believe it? READ THE BACK LABELS ON THE TWO PRESTONE PRODUCTS - SAME OXYLATE ORGANIC ACID SALT CORROSION INHIBITORS.

 

[Ryan00TJ]

Michael, I recently swithced my 2000 2.5L TJ and my brother's 98 4.0L TJ to Zerex G-05 Extended Life Coolant. I found it at Autozone in the Zerex Gold Jugs. Chrysler, Ford, Mercedes have all switched to this formula so that will tell you something there. If I owned your vehicles this is what I would put in their coolant systems. It's a little more expensive than regular green $2 or so but I think it's worth it.

Unless you have a block drain plug the easiest way to change and flush the old coolant is to drain the radiator, fill with new distilled water, 50 cents per gallon at Wallmart, run until thermostat opens and coolant begins to circulate through engine, then drain radiator again. Repeat this process until clear water comes out of the radiator when draining. Now you have clean distilled water in your block. Now add proper amount of coolant to the radiator, top off overflow with 50/50 mix and your done.

This procedure requires you to know your coolant system capacity which for the 4.0L is 11 qts according to my FSM. BTW I've tried to get the coolant drain plugs out of the block on both my TJs without any good. HTH

 

[Hirev]

I know from now on my rigs are going to get $7.99 a gallon Zerex G-O5. Just replaced a Prestoneized radiator in my 123,000 mile Yota. Changed every 2 years. The way I look at it, It can't be any worse.