Whats is the final call with DEXCOOL?

[richtazz]

In my experience, I believe it should be changed more like every 3 years, 100k miles as it seems to start sludging up and getting acidic after that.

[BNaylor]

The only time I have seen Dex-cool sludge is when there is a bonafide problem with the cooling system or gaskets like intake going South. I've run Dex-cool in most of the GM cars I own up to 5 years since I don't ever come close to 150K miles before 5 years and it looked as good as new when replaced. That includes running various tests to include conductivity. I use Prestone EL coolant in my GTP but that was for other reasons like cost and nothing to do with the pros or cons of Dex-cool. It is replaced annually but it is also 5/150 coolant just like Dex-cool.

Also, the aftermarket EL coolants will sludge just like Dex-cool if there are issues.

[01gtprocket]

went to walmart bec my coolant light came on so im reading ingrients on raditor fluid at 7am... guess i was bored

the dexcool i bought was made by prestone. and i noticed tht there was a prestione right next to the dexcool/ and the ingrients matched. then i checked the ingrients on the walmart raditor fluid and everthing has the same ingrients..

so i bought the dexcool bec of the name. otherwise are we just buying the name?

[CrazyHorst]

Here's a different take.

The "older"design" GM pushrod engines ala 3800, 350cid V8, 4.3L/262 V6, 7.4/454, 3.1/3.4 60 degree V6 that powered the world all use an non-pressurized overflow bottles which see regular exposure to air, possibly more as the radiator cap ages, etc.

The "newer design" engines & corresponding vehicles such as L850, 4.8/5.3/6.0L V8 all use pressurized overflow bottles which generally see no airflow.

IMHO there's something to this, rooted nearby the above. It could be investment in better sealability internal to the engines as well as the designs evolved. The Dexcool complaints and problems I've heard of all are in the first category of engines. I've heard of none with the second category.

Again, just my personal observations of owning several vehicles and talking to people about repair issues.

[transamman1]

I know this is an old thread but have to say something about dexcool aka"dexkill" I'm a mechanic coming on 30 years now..every single engine Ive gone head or intake gaskets on have had dexcool..burnt orange clay buildup around cap water pump hoses radiators u name it...I won't touch the stuff...every vehicle my family has I've drained and flushed that crap out and used conventional green 50/50.. sister has a 3400 sfi in her grand am pushing 310k and still burns the tires