I have a 2000 Dodge Durango with a 5.2L Magnum engine. At 42,000 miles,
on March 29, 2005, it started leaking anti-freeze coolant. The dealer
indicated that 3 of the 10 freeze (core) plug were leaking due to
corrosion. Then, at 64,000 miles, on August 24, 2006, it happened again
but this time only 2 of the 10 freeze (core) plug were leaking due to
corrosion. Is this a defect?
I am having a hard time understanding how could this leak so easily and
so quickly. Is this a design problem with the SUV Truck? Thanks for
I agree too that it is a maintainance issue. When you get freeze plugs
leaking, it is usually a sign of improper antifreeze mixture that is
letting corrosion take place. When a few leak the others are not far
behind. There is a few thing you can do to mitagate it thought in
future. Run more than 50/50 antifreeze for one because 50/50 is not
enough somethime for good protection (I alway use at leat 60/40 and
usually 70/30). I have a 52 year old tractor that I run about 80/20 or
more in because I do not want to have to worry about corrosion in it
as parts are rare. I have not changed the coolant since I got is over
20 years ago when I put 80/20 of better in it fresh and it is still
clean as day I did it and tractor sees about about 30 to 50 hrs of
usage a year even today. It never over heat on the even the hottest
days bush hogging (I do though) When I top it off once a year I always
use pure antifreeze too There will be those that aurgue the higher
antifreeze levels are not best but this is simply no true and it will
cool fine and protect even better. Antifreeze is densor and has a
higher abilty to abosurb heat to. It does take less energy to boil
gycol and convert it to steam than water and hence where the some say
water cools better but in a liquid state is takes more energy to raise
a gallon of glycol one degree than it does water and therefore more
"energy" to cool it since it stores more heat. You could also use a
lower pressure cap to lessen strin on plugs and minimize leaks when
they occur. I have been using 7 to 9 PSI caps for over 20 years and I
never have any heating issue even when traveling through the great
plains in 100 degree plus heat with 70/30 mixtures as higher levels of
gycol also raises boil point too negating the need for higher prssure
for boil over prtection. In theory if you ran pure antifreeze you
would not even need a pressure cap as it boils around 340 degrees
though in a pure state is freezee around 10. (ethylene glycol which is
coomon anti freeze) As a foot note if you use propylene glycol (non
toxic anti freeze as marketed) it has it highest boil point and lowest
freeze point in its pure state with no water added and is used is
severe artic cooling requirements.
I have been following this thread (and many others!) and can no longer
remain silent while such wholesale BS is propagated through this newsgroup.
I would caution the OP to dismiss the Snomans reply in its entirety since it
is absolute hogwash!
It is highly likely that it is indeed a maintenance issue, but NOT due to
the incorrect antifreeze mixture. The factory recommended 50-50 mixture is
the IDEAL ratio and should be adhered to in spite of anecdotal "evidence"
posted below. More than likely, the freeze plug failure is due to corrosion
from infrequent cooling system service. Your owner's manual recommends an
initial antifreeze change at 3 years or 45,000 miles and every two years or
24,000 miles thereafter. Antifreeze does two things... keeps the engine
from freezing in winter and also contains corrosion inhibitors and silicates
to promote internal engine health. Over time, the antifreeze properties
remain relatively constant but the anti-corrosion compounds break down and
are no longer effective which leads to cooling syetm failure thus the need
for periodic coolant service.
Now, onto the BS.
When a few leak the others are not far
Unless you live in the extreme north, NEVER run more than a 50-50 mixture of
antifreeze and water. A 50-50 mixture of coolant will give you ALL the
corrosion inhibitors you need to keep your cooling system at peak efficiency
if it is maintained properly. A 50-50 mixture will provide freeze
protection down to -34 degrees F which is adequate for most of the US and
Canada. If your climate requires, you can go to a MAXIMUM of 70-30
antifreeze and water, but this is rarely needed and offers NO benefit other
than additional freeze protection.
(I alway use at leat 60/40 and
This is sheer idiocy. Why would you abuse your equipment when using the
proper coolant ratio and periodic changes are so easy? Just because it has
worked for you means that you are lucky, it doesn't mean that you are
correct. You cannot determine through visual inspection the amount or
effectiveness of the corrosion inhibitors remaining in the coolant. A
hydrometer will only show freeze protection.
There will be those that aurgue the higher
This is simply not true in spite of your belief that it is.
Antifreeze is densor and has a
This is pure BS! Therrmodyamics 101. The ability of a material to conduct
heat is called thermal conductivity. It is usually expressed as W/m K. The
thermal conductivity of water is .67 and the thermal conductivity of
ethylene glycol (antifreeze) is .25, thus water is significantly better at
The ability of a material to "store" heat is called its specific heat. It
is usually expressed as kJ/kgK. The specific heat of water is 4.184 and the
specific heat of ethylene glycol is 2.38, thus again, water is much better
at storing heat than antifreeze.
Only one other liquid comes to mind that is better as a coolant than plain
water and that is mercury.
You could also use a
At last, a correct statement, but this approach is a band-aid at best.
I have been using 7 to 9 PSI caps for over 20 years and I
You have not had a problem because of your cleverness, you have just relied
on dumb luck
In theory if you ran pure antifreeze you
However, you run a significant risk in engine overheating because the pure
ethylene glycol cannot carry the heat away from the engine fast enough, nor
can proper heat transfer occur through the radiator due to the physical
properties mentioned above. This is simply bad advice!
The bottom line is this. Do NOT take what Snoman says as gospel. I have
seen on too many occasions that his advice is flat-out wrong. I don't know
where he gets his information, but it is NOT from knowledgeable
professionals. I have remained silent up to this point, but I can no longer
sit quietly while such mis-information is spread in this group.
Snoman, your participation in this group is welcome however, please take the
time to verify that the info your provide is correct and is based upon sound
engineering principles and recognized industry practices. To do less does
the readers of your posts a great disservice.
I hope this clairifies the information in this post.
DaimlerChrysler Serviec Manager
Member Society of Automotive Engineers
Mike's signature says it all. Notwithstanding *good* shadetree mechanics (I
use the term with affection), one does not become a service manager and a
member of ASE without knowledge. Kudos to Mike, Tom (and many others) who
offer their decades of experience and wealth of knowledge!
Mike, I wholeheartedly second your post. You saved me a bunch of typing. <G>
I don't know where ole Snowy comes up with this stuff, to somebody that
doesn't know better it sounds good but it just misses the mark.
I am very appreciative of all your time and responses, but the logic
about the maintenance does not make sense.
As stated above, it was not 2 years yet between the two leak
occurrences (March 2005 to August 2006 = 17 months).
It also has not been 24,000 miles yet between the 2 leak occurrences
(42,000 miles and 64,000 miles = 22,000 miles).
Even if I brought the SUV in to the dealer earlier to replace the
coolant, the corrosion already took place prior to the maintenance
cycles. Both leak problems occurred before each of the recommended
maintenance cycles. If I had the opportunity, I would have brought the
truck in for maintenance, but it leaked first prior to both maintenance
I can give you guys more background on this if needed. I am interested
in keeping my Durango a long time so I am looking for a long term
THis is the problem stero types. Detriot uses 50/50 still because over
millions of vechicle you save tens of millions of dollars a year for
profit. THere was a time that detriot said 40/60 was best too. The
problem is aggrevated by the mixed metal contect in engine blocks that
increase galvanic reactivity and water is very reactive too. The less
of it the better. THe BS is is where people blindly folow detriot that
wants you to by another car in 3 or 5 years or take it in for
servicing. The last thing they want to do is build one that really
lasts and reduces demand for their products. I keep some vehicle a
very long time and I could send you pictures of overflow tanks and
radiator that are as clean as they day they were built 17 or more
years ago from using 70/30 but you would say that they were doctored
or that I used a new or cleaned ones so knock yourself out. Also by
your BS people living in northen states are screwd because 50/50 will
not cut it and even 60/40 will not either in a few areas and I for one
have lived once where 40 below and colder was common in winter and
50/50 whould hae been worthless. You want to was your money you can
but do not dismiss something as BS because you do not understand the
physics behind it. Detriot loves lambs to can be easily lead to
On Sun, 03 Sep 2006 16:35:07 GMT, firstname.lastname@example.org wrote:
I have electrical and mechanical engineering background yours is likey
pure BS. I would expect a answer like yours from someone that is
really clueless on how and why things work. What you do not understand
you dismiss as BS and attack the source of it.. Knock yourself out
if this is the only way you can get your fix..
What school/university did you attend??? What degree do you have??? The
answer to this and the v-10 timing concern will shut a bunch of us up. Of
course, no answer to either one will result in that pure BS you're talking
I would expect a answer like yours from someone that is
Again Detriot loves these lambs. You know they spend a lot of time and
writing the owners manual at a low enough comprehension level for you
guys to read and take as the bible. If you would REALLY read you might
I have lived in northern MN, and ND for all my 47 years and a 50/50 mix
works fine. In fact even less will get you by, but the coolant may turn to
slush on the coldest days. And believe me, I have seen -40 more than once!
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