My understanding is GM claims that the DexCool coolant is responsible for
intake Gasket Failures.
My understanding is also that the intake failures have been happening since
around the mid 1990's. Isnt that before they even started using Dexcool? If
I am wrong on that then I stand corrected. In any case if GM new that the
Dexcool was the problem then why didnt they just have a recall to drain the
dexcool and refill all the cars with the green stuff? Would this be because
GM would then be admitting to a known problem? The problem has been around
for 10 years unaddressed year after year. GM used to make some of may
favorite cars...Hotrod Chevelles, GTOs Camaros etc. But GM ....you done
changed. I just dont know if I still want to be your friend.
On the contrary. GM says Dex-Cool is god's gift to man. They wouldn't
still use it otherwise. Any problem is the owner's fault for not
checking the coolant's quality with a refractometer often enough.
(according to the AC Delco guy that taught the last after-work training
seminar I attended.)
Which would, of course, be higher if the Dex-Cool to water ratio was
higher or lower than ideal. The statement from the Delco rep, may or
may not be hogwash, but supposedly....
If the Dex-Cool to water mix is not within a few points of the 50-50
range, the mixture becomes VERY acidic, and THAT is the owners fault for
not maintaining the 50-50 mix, not the Dex-Cools fault. The main
dilution of the ideal mix comes from air in the system.
How does air get in? Bad radiator cap.
GM never said they were five year caps, just five year coolant.
No, GM does not think that Dexcool has anything to do with
gasket failures. The intake gasket failure is due to a poor design
that relies on low clamp loads and the fact that a technician
ought to know how to torque bolts and use loctite in these
Intake gasket failures on GM 60 degree engines have been happening
since they started making the engines in the mid 80's. When they first came
the X-bodies and A-bodies....we were doing intake gaskets all the
time. Same problem.....coolant would get in the engine oil. Different
style of gasket....same basic end result...coolant in oil. There has also
always been a problem with oil leakage from the RTV end gaskets.
This is due to two problems.....poor preparation of the surfaces by
the technicians....and the fact that RTV gaskets will inevitably leak
no matter what you do.
How can you blame it on the technicians or poor preparation on a
factory new engine? It is GM's fault - pure and simple. A design that
uses low clamping loads combined with gasket materials that cannot
seal under low clamp load conditions is poor design, no ifs, ands, or
buts about it.
Not fixing the root problem is the result of the bean counters looking
at the cost to repair the desihn vs the cost to repair under warranty,
taking the average lifespan into account.
Simply put, they figure it is cheaper to replace a few thousand
gaskets a year than to redisign the engine.
What they fail to take into account is the loss of sales due to
customer dis-satisfaction and anger.
And they wonder why they couldn't sell enough Oldsmobiles to make it
worth while retaining the marque - and now either Pontiac or Buick (or
possibly both) may well follow suite.
Used to be the cry was "kill all the lawyers".. Soon it will be "kill
all the accountants". Between accountants and lawyers, manufacturing
jobs are relentlessly being driven out of the USA , and close behind,
out of Canada as well.
I was talking about the RTV section of the gasket. Eventually
they all do leak, but I and other techs that I know that take the
time to use RTV properly don't see the intake gasket back leaking
from the RTV very often. But the one's that dont take care, usually
are re-doing them.
The entire engine design is suspect....but you are right, bean counters
will do us in.
I am a member of this club, 98 Lumina 3.1 once when it was under warranty
and now again at almost 80k! I plan on replacing the coolant fluid with the
good old fashion Prestone green antifreeze. Does anyone think all this
trouble may be from the new dex coolant or just crappy design?
wrote:<BR>>><BR>>>> How can you blame it on the technicians or
poor preparation on a<BR>>>> factory new engine? It is GM's fault -
pure and simple. A design that<BR>>>> uses low clamping loads combined
with gasket materials that cannot<BR>>>> seal under low clamp load
conditions is poor design, no ifs, ands, or<BR>>>> buts about
it.<BR>>><BR>>> I was talking about the RTV section of the
gasket. Eventually<BR>>> they all do leak, but I and other techs
that I know that take the<BR>>> time to use RTV properly don't see the
intake gasket back leaking<BR>>> from the RTV very often. But the
one's that dont take care, usually<BR>>> are re-doing
them.<BR>>><BR>>> The entire engine design is suspect....but you are
right, bean counters<BR>>> will do us in.<BR>>><BR>>>
Ian<BR>>> <BR>> <BR>></FONT></DIV></BODY></HTML>
Nice dexcool article you mentioned.
I have a question about
coolant recall for my 2000 Buick regal (LS, nonturbo).
I have been changing dexcool every year and it has 65000
miles. GM is sending me recall notice every 3 months
to care recall. The recall will expire in July 2005.
My question is since I have been changing coolant
regularly and no overheating problem, do you think
I should still take the care to delaer or just ignore the recall.
And if you can explain what's in the recall besides
tightening the bolts.
After cleaning the surfaces real good I use McKanica red High Temp RTV
around the corners of the intake as well as round the coolant passages
on the gasket. With some thread locker and that McKanica RTV there are
no repeat leaks. Great stuff!
In my experiance Dexcool is still far better if the leaks are repaired
correctly. When I remove plastic gaskets that have been running
conventional green coolant I find most of the plastic material is
missing and whats left of the gasket is very brittle. I also find a lot
of pock marks in the aluminum which will never re-seal without good RTV.
However the rubber beads built into those gaskets are usually swelled up
which is the "only" advantage the silicon based coolants give you.
(until they blow out from lack of plastic material)
Dexcool contains a plasticizer which softens up the plastic gaskets ever
so slightly. For the 60deg motors this is a huge problem considering
they dont have a very good clamping load on the gaskets and the gaskets
are taller and thinner around the passages. For the 3800's lower intake
gaskets this isnt much of an issue.
I am very angry that the intake gasket failed on our 2002 Oldsmobile at
40,000 miles or so ... well before the first coolant change was even
scheduled. This was not the result of a bad service tech, but a horrible
Normally I have a low view of the class action lawyers, but when companies
put these kinds of problems knowingly in the field for decades, well, they
have it coming to them.
Well, wait until everyone starts seeing all the head gasket failures
that we are seeing on the later model 3.4 engines. Of course,
the head gaskets are simply seeping coolant to the exterior
of the engine, but they are leaking all the same. Oh well, keeps
When I was having problems I re-torqued the intake manifold bolts. There
were loose bolts. This seemed to have done the trick. This also worked on
the valve cover the oil pan and a part around the output shafts on the
Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here.
All logos and trade names are the property of their respective owners.