THE PROBLEM IS THE SOLUTION
Perhaps one of the most important elements in
your cooling system is the coolant. It needs to be clean, non
corrosive, non conductive and have freezing and boiling properties
that are appropriate for the conditions. Rule of thumb is to change
the coolant every two years. Some cars are coming equipped from the
factory with so called "extended-life" coolants. One of the more
popular extended life coolants is Dex-cool.
Will it last 5 years?
5 years or 100,000 miles?
The "recommended" service intervals of Dex-cool coolant is 5 years
100K miles and in some cases 150K miles. These extended service
intervals have not proven to be any thing but trouble for the
consumer. In some cars, the coolant tends to turn to a thick, gooey,
sticky, muddy, gritty, orange corrosive gel that fouls the radiator,
heater, plugs coolant passages in the intake manifold and heads, and
many times starves the water pump, resulting in overheating, and
leaking. Mounting evidence suggests that Dex-cool reacts with
plastic sealing surfaces, allowing leakage at the intake manifold
gaskets. The best thing to do without voiding any warranty, is to
change your coolant every two years with the recommended coolant.
CHANGE THE COOLANT EVERY TWO YEARS!! ESPECIALLY IF IT DEX-COOL!!
DEX-COOL IS THE WORST OFFENDER. DEX-COOL DOES NOT LAST 5 YEARS OR
1000,000 MILES*. Dex-cool pictures
Will it last 150,000 miles?
This Dex-cool goes 150,000 miles?
General Motors introduced Dex-Cool to certain lines of vehicles in
1996. Since it was formulated without the addition of silicates (the
corrosion inhibitors in green antifreeze) a different corrosion
inhibitor strategy was needed. Organic Acid Technology or OAT is the
inhibitor part of dex-cool. Unfortunately, the dex-cool is capable a
rather nasty breakdown. The residue it leaves behind is very sticky,
and likes to find areas in the engine and other areas to "drop out"
or "fall out " of solution and stick to the wall surface of engine
and radiator. If the residue is in the radiator, hoses, or recovery
bottle, it's relatively easy to clean and remove the debris. When
the residue is in the heads and block, only a chemical flush will
remove this orange mud. In some cases, the orange mud hardens, and
seems to expand or push the gasketed surfaces out of position,
No mileage claim here.
There are some in the industry (including GM) that claim that
exposure to "air" causes the Dex-cool to come apart, and that faulty
radiator cap design is the culprit. They say that with a faulty cap,
the cooling systems allow evaporation, allowing the Dex-cool to
destabilize, weaken, and lose it's already marginal protection, and
then turn muddy. Others say that poor cylinder head design traps air
in pockets, allows condensation and ultimately dilution, resulting
in aluminum oxide formation and deposits. Neither of these theories
completely explain the whole picture, and these are not a
universally shared opinions. If air were the culprit, all Dex-cool
systems in every vehicle with a recovery (overflow) container would
suffer the same problem. They don't. Reverse flow V-8's would be
immune. They aren't.
Most insulting about the whole issue is the GM dealer response to
the problem. While the vehicle is still in warranty - turn a blind
eye. Yet once the vehicle has gone past the warranty period, the
solution is simple: replace the radiator, hoses, intake manifold
gaskets and maybe the water pump. I believe it is this response that
has spawned the current class action litigation.
There are about 72 brands of coolant on the market today. 95% of all
these coolants are manufactured using ethylene glycol and mixed with
50% water when installed in a car or truck. Dex-cool is no
exception. The differences between coolant brands comes from the
additives that enhance the corrosion protection properties. For
years this protection came from silicates, but more recently coolant
manufactures have moved away from silicate enhanced coolant, to OAT
enhanced coolant. Silicates are discussed more here.
Organic Acid Technology refers to the type of corrosion and rust
inhibitors used in the make up of the coolant. OAT formulated
coolants provide "background" or reserve protection (works like a
vitamin), and as such, tend to react more slowly to situation
changes as opposed to the faster acting silicates (works like an
aspirin). There are several ingredients that constitute the OAT,
including carboxyl, benzoate, borate, triazole, and 2-ethylhexanoic
acid. Depending on the brand of coolant, these ingredients may vary.
Vehicle manufactures increasingly are moving to OAT coolant, and may
have slightly different formulations for different markets. European
vehicles have used OAT formulated coolant with an addition of some
low level silicates to provide further and faster protection. These
are called hybrid inhibitor coolants because they contain both
silicates, and OAT formulations. More discussion on coolant,
inhibitors, and silicates are discussed here.
Dex-cool manufactures continue to insist that Dex-cool will last 5
years and 150,000 miles, and that the problem is lack of
maintenance. In other words, you should be maintaining your
maintenance free cooling system.
The bottom line. There are lots of coolants out there. Lots of
inhibitors out there. Lots of cars out there. Only certain cars have
thick, gooey, sticky, gritty, muddy corrosive gel fouling their
cooling system, causing overheating and leaking.
Call it what you want.
We call it Dex-cool.
Ford doesn't like Dex-cool