: Should I use Dex-Cool?



newcaddyowner
12-29-06, 10:26 AM
I just bought a used 2003 DeVille on November 21st. The day after Christmas the "check coolant level" came on and it's low. I read the manual and it said to use only Dex-Cool but I've read on the web that it may not be the greatest thing. I also heard that GM issued some bullteins that relate to sludging and intake manifold gasket problems. Should I put something else in? If so, will it cause problems if it's mixed with what's already in there?

codewize
12-29-06, 06:35 PM
If there's Dex-Cool in it now then fill it with Dex-Cool. And hurry, air pockets in the system are one of the most detrimental things to the HEAD gaskets not the intake gasket.

The question is why is the coolant low? Coolant system maintenance is very very important on the N* Failure to maintain the system properly is very often the cause of head gasket failure. Running with low coolant is bad bad bad and not because of heat.

Also note that you MUST maintain an 50/50 mix. Don't slack off on this. As I said, proper coolant system maintenance is very very important. Dex-Cool is fine and is recommended.

To answer some of your other question, yes you can mix coolant but you'll loose all the good longer life properties of the Dex-Cool if you do.

I have never seen a bulletin regarding intake sludge or any intake problems at all. No have I ever read anything bad about Dex-Cool, though someone else asked that also.

GreenMachine
12-31-06, 02:54 AM
You'll read alot of problems with dexcool...but rarely see a problem from it in Cadillacs. The only time you really see a problem in the caddy's is when its neglected past its change interval.

Try adding some of the GM Coolant Supplement Pellets to the upper radiator hose (NOT SURGE TANK) this could cure your leak. If that isn't an option have the dealer or use die to find it.

MonzaRacer
12-31-06, 03:44 AM
Honestly I dont like Dex it has problems I have stated in the other Dex-Cool post.
I have no problems with extended life antifreeze just the one additive that Dex uses that DOES cause problems in some engines (ones that use lots of plastic in the cooling system. I see its affects on gaskets, outlets and intakes.Just removed a 3.8 intake with plastic intake degraded and it filled engine with coolant,,, new intake at 53k and its good as new, his daughters 3.4 equipt car just got new intake gaskets at 43k and they were soft an gummy/brittle where coolant got to them. Ask them if they wanted Dex-cool in them or green and change it reguarly and they went with green. Owner ask about water pump seal problems and I told them if you can trash a carbide seal in one(the general problem for leaks is bearing wear and the wear area that the seal rides on not the seal) then you have done something since its usually loose casting sand washing out and simple work hardening and bearing wear causing shaft play. Nothing in the green will hurt a waterpump,,,unless you try to run it 100k.
But I really like to flush the cooling system with water, then refill it with either G-05 Extended life Antifreeze, and distilled water (if you use the majority distilled water then the additives dont fight the hard water as much, just the small amount in the block ) or green and distilled, And I recommend if you drive in the 15k to 20 k a year to drain and fill every fall with green and service the thermostat. I like to replave them as they are in constant motion at temp regulating the coolant. OH anif you think putting in a different t-stat than whats recommeded, dont the computer isnt programed to run a cold engine as well and it will cause over fueling and extra wear.
Good lUck

Ranger
12-31-06, 04:16 AM
Where was the 3800 intake degraded from Dex?

MonzaRacer
12-31-06, 09:44 PM
Well it wasnt around the EGR as everyone was telling me casued it it was simply a soft plastic edge giving way.
I have seen Dex tear up lots of plastic cooling system parts. you guys can defend it but it has even got press in Motor Magazine in a coolant article. I like extended life antifreeze but not Dex, if Texaco removes 2EHA from it and advertizes it as reformulated then I would use it again as I like AC Delco parts, I am gonna build a new tranny and use the new DexronVI ATF as it has some great specs.
I am an ASE Master Automotive Tech and I have seen DEX problems for years and regardless of someone hugging a jug of it and telling me its the latest and greatest I know its junk in a system with plastic parts in it. IFyou use it in a completely metal system then you will have a great product in your cooling system.
OH and i know how to diag leaks and the leaks came from well away from any other source than coolant damage.
This has been an ongoing subject at work and I had a fella who restored his Corvette and we installed Genuine GM Dex-Cool in a 63 327 FI convertible as its gonna see garage time for the most part as he is going to Iraq. I told him what it did , we flushed both his new truck with the 8.1 and installed G-05 and his wifes new Cobalt got it too.
OK Im done, I know when I say isaw a problem in something people will crucifiy me but I hate AC Delco batteries too.
Ill stick with my Optima's.
Lee

codewize
12-31-06, 10:59 PM
I'm not bashing you but I want to say that certifications don't mean crap to me. The guys at my dealership are all certified to they don't know shit about engines.

I asked for pricing on a half case gasket and then defined it as the lower crank case gasket, as it is in the book, and they said they never heard of such a part.

I know people with Cisco certifications that don't know shit about routing.

I don't know you personally but being a ASE Master Tech doesn't mean crap to me. It just means you went to some classes where they force fed you the info that was going to be on an exam and you passed where passing is probably 70%. I need someone to be right more than 70% of the time in my life.

Again I'm not bashing you directly and doctors are the same way. 70% on the bar exam and Viola, you're a doctor.

I don't know about other vehicles but I do know that DEX is the recommended coolant in the N* and it works. I don't think Dex-cool is the recommended coolant for a 327 though. Follow the manual and life will be better.

I know that I've tried every or almost every other battery on the market and AC Delco works. As I mentioned Interstate is also a great product as is Optima, which I didn't mention.

N0DIH
01-02-07, 09:43 AM
Use distilled water too. Don't use tap, and from what I just read, don't use softened tap water. That adds to the corrosion problems.

billytheshoe
01-05-07, 07:47 PM
Hey guys, I just got a 95' eldo and It has green and appears to have been maintained. Would I be better off sticking with the green 50/50 rather than dex 50/50?

Ranger
01-05-07, 08:03 PM
Stick with green. Appearance means nothing as aluminum will corrode but does not rust, so on an aluminum engine, coolant will show no signs of depleted corrsion inhibitors. It will still look like new even after 20 years.

MonzaRacer
01-06-07, 02:07 AM
Hey Codewize, I could care less how stuipid your local dealership is but I for one DO take my job seriously and study the technology in depth. If you dont think my certs mean anything well then go jump off a bridge.
As for a parts guy not knowing that several people use different names for same part thats not my problem as I know several names for parts.
I can write service, look up parts(and usually get it right the first time) and diag the problems and install the proper parts in most vehicles to repair them.
Presently I am building/designing a computerized FI system that will use DIS and Flex Fuel capabilities.
OH and I do also build some hig dollar, race engines and do date after 18+ years I have only had 3 engines die and all were because of owner abuse/neglect/stupidity.
As for most techs the L1 cert test is a bitch, the basic auto cets are a little easier.
OH and as for working on cars I just invested $5k in a new scanner and looking at trading it in for the full monty that runs about $10k. I have spent more on the proper tools to repair cars than anyone of you have spent on one of these cars (this would have to include all the interest I incured too but folks I still have almost a grand on side accounts outstanding not including the finacing on the new scanner) unless you have some supper hig dollar limited edition model.
Heck I carry $10 k in tools in 2 boxes the size of brief cases and I bring those home every night, but that doesnt cover the other $40k+ I own at work and I probably have another $10k to $15 at home.
Oh and in Febuary I am going to a 3 day Evap diag class, and last year I got to go to the 2 week Diag class in Denver.
I do diag everyday and can out class most diag techs in town I work in ,,except our lead tech who has been at it for a lot longer and he is very good too.
OH and I hope you never need a good Diag tech or are good your self at it..
I love people that think a code or a scanner fixes the car. I make a lot of money at work doing actual diag after someone goes and gets "the codes" and throws lots of parts at it.
Sorry but if you want to trash my certification ,you better get to know me first.
Lee

codewize
01-06-07, 10:41 AM
I thought I was clear when I said that I wasn't directing that at you personally and that I didn't know you personally. I was speaking in general terms about my experiences with people that brag about being certified in things.

I also think you'll find several people who feel the same way about the techs at their local dealership.

I appreciate that you care about your profession and invest in expanding your knowledge. You're a rare case in today's world as I believe I am.

CTS-LS2
09-09-08, 03:56 AM
I'm not bashing you but I want to say that certifications don't mean crap to me. The guys at my dealership are all certified to they don't know shit about engines.

I asked for pricing on a half case gasket and then defined it as the lower crank case gasket, as it is in the book, and they said they never heard of such a part.

I know people with Cisco certifications that don't know shit about routing.

I don't know you personally but being a ASE Master Tech doesn't mean crap to me. It just means you went to some classes where they force fed you the info that was going to be on an exam and you passed where passing is probably 70%. I need someone to be right more than 70% of the time in my life.

Again I'm not bashing you directly and doctors are the same way. 70% on the bar exam and Viola, you're a doctor.

I don't know about other vehicles but I do know that DEX is the recommended coolant in the N* and it works. I don't think Dex-cool is the recommended coolant for a 327 though. Follow the manual and life will be better.

I know that I've tried every or almost every other battery on the market and AC Delco works. As I mentioned Interstate is also a great product as is Optima, which I didn't mention.

Last I chekced, you took a bar exam to be on the bar association in your state, you know PRACTICE LAW, not medicine... maybe the MD's should take your advice and defend the out of control malpractice suits against the fact that everyone will die... its just not fair/legal if its your relative; then the doctor must have done everything wrong.

Submariner409
09-09-08, 08:56 AM
CTS, Where in the world did you dredge this old thread from ???? Old news, old replies, overtaken by events.