Jump to content

Redfox340
 Share

Recommended Posts

Ok, after some basic searching I've found that half of the members on this board are for Dex-Cool and the others swear by the 'green' coolant. I know if you mix the two together you get a nice thick mud sludge in you radiator, block and every where else the coolant runs through... the question is this: which is better for post 1995+ with the Dex-Cool sticker? I got an e-mail concerning this... please read (his comments in red; my remarks in blue):

 

I am getting conflicting information from mechanics. Should I replace Dex-Cool in my 1996 GMC van with conventional "green" anti-freeze?

 

Well, if the Dex-Cool sticker is installed under the hood, I would stay with the Dex-Cool. However, Dex is over-rated that you can change it on 100K miles intervals (according to my quick lube shop sources)... so bottom line: I would stay with the Dex but change it more often. You've got nothing to worry about it. Are you having problems with overheating? Or did the green and the Dex mix? Let me know what's up, and wish you the best out of luck!

 

When a local shop recently changed my anti-freeze, they changed my coolant to the "green" anti-freeze even though under the hood it says to use Dex-cool. The local shop said it would not hurt and even GM recommended changing back to the "green" anti-freeze. Since then I have spoken with another mechanic who said I should have it changed back to Dex-cool. What would you recommend?

 

Thanks for any input!!!

 

- RedFox340

Link to comment
Share on other sites

Here's the low down... and people can correct me if they think I'm wrong.

 

The supposed long life anti freeze isn't....change it every year anyway....

 

It is BETTER for one purpose. ALUMINUM!!!! the heads and intakes and water pumps and half the motor on our cars are aluminum.... the GREEN antifreeze will CORRODE aluminium given enough time exposed do to it's phosphate content...the ORANGE antifreeze has a different type of phosphate in it that wont corrode the aluminum. There is supposed to be an additive that you can add to green to make it aluminium safe...but I wouldn't trust it...

 

that being said I would run the orange in any car that has aluminum somewhere in the coolant system......

 

the green only has one benefit...it cools about 5% better then the orange....you would really only need this little difference if you were rally/scca or long distance racing and every little bit counts....and if your doing all that...your going to be flushing the system after every race anyway do to remove deposits do to thermal break down of the fluid.

 

hope this helps

 

Dave

Link to comment
Share on other sites

If it came with long-life (orange), stick with it. There have been stories of rusty mud developing when changes are made. I haven't heard yet what the root cause of the mud really is.

 

If it came with green stuff and you want to change over, it can be done from what I have read. However, you ever notice how the green stuff leaves behind a kind of oily film? This has to be removed completely in order to enjoy the benefits of the long-life orange stuff. Me, I'd just stick with whatever came in the cooling system and not worry about it.

 

The problem with the green stuff, Prestone in particular is the silicates that are used in it. Silicates are used as a corrosion inhibitor. Silicates are very abrasive and tends to wear water pump seals and shafts. Also, once the coolant gets old, the silicates start to come out of solution and begin to plug up radiators and heater cores. Yeah, the white, scale-like stuff you see on the ends of your radiator tubes.

 

Is there green stuff without silicates? Honda for sure makes silicate-free coolant. I think Yamaha does too. The Honda stuff is expensive at $14 a gallon. If you go this route, buy the non-premixed stuff. More economical; you get twice the coolant when mixed for the same price as a gallon of pre-mix.

 

I'm beginning to change over all my vehicles (Yamahas, Chevys, and Toyotas) over to silicate-free green stuff.

Link to comment
Share on other sites

Drache,

 

You're close... Saturn, Cadillac and other aluminum radiators needed phosphate - free coolant. So, those cars of GM needed it from anywhere of 1991 - 1994. 1995+ and almost, if not all 1996 models had Dex-Cool... Thanks all for the input and personal suggestions! I'm personally using the green and change it every year... it's too easy not to.

 

 

Paulo57509,

 

I'll have to look into the silicate - free coolant, sounds good!

 

- RedFox340

Link to comment
Share on other sites

hmm you could be right... but what I was taught by prestone was that the green and the orange and different types of phosphates.... different phosphates affect different metals... but seeing how I dont have a dex cool bottle here or a regular gylcol bottle... I will have to wait till tuesday when I go back to work to verify.... you see aside from my main job as a computer tech.... I am also currently employed by napa here.... I was the assistant manager for adavance auto here..but they kept trying to make me work 80 hours a week which was very definatly interfearing with my tech work....now which do you think takes priorty....35$ an hour or $11.75?

and before that I was a psm for auto zone...it's sorta like a cross between a parts pro... and a manager.. I guess you could say I was the head parts pro...I do the car stuff because I'm good at it ...and it helps me aford to build my race cars 8) (I just realized I have go so far off topic I am going to bed... it is 1:30 am here and I am rambling while typing goodnight)

Link to comment
Share on other sites

I use Dex because I work at a dealership and there's always tons of it left over after engine work. I have it in all of my vehicles, even my '74 Dart and my '83 Malibu.

 

I'm not sure about the properties of dex, but isn't one of them the fact that it's safer around animals/pets?

Link to comment
Share on other sites

NO it's not safer around pets..... thats a different anitfreeze....and it's not realy any less toxic per se... you just have a better chance of saving the animal if it ingested it then the other stuff...that and it been bittered to try to make the animals not drink it

Link to comment
Share on other sites

If it came with long-life (orange), stick with it. There have been stories of rusty mud developing when changes are made. I haven't heard yet what the root cause of the mud really is.

The "mud" is what happens when Dex-cool has came in contact with the "green" stuff or if it is old. I just had to replace the water pump in my '96 Cutlass a few months ago and I flushed all the mud out. The stuff stinks like crap and looks like it also. I think that the Car had the original Dex-cool since '96, when car was made.

Link to comment
Share on other sites

Propylene Glycol is the antifreeze that's safe around pets. I don't know if it's still made, but a company called Sierra made/marketed it.

 

Dex-cool and the conventional green stuff are both highly toxic Ethylene Glycol.

 

I ran Prestone green coolant in my '89 Cutlass exclusively and changed it every year. It ate my head gaskets from the inside-out. Since then, I've switched all my cars to Dex-cool and haven't had the slightest problem with it. A standard flush is all it took, and the Dex-cool stays bright orange and sludge-free.

 

GM has never reverted to green stuff, I don't know where you got that, but GM still swears by Dex-cool.

 

MAYBE in a very controlled environment, Dex-cool could last 100k miles. Personally, I wouldn't leave it in there that long. Change Dex-cool with the same frequency that you changed the green stuff, and I don't think you'll ever have any problems with it. I've logged many thousands of miles with Dex-cool in many W-bodies, and I personally think it works great. Also, if it doesn't have the Dex-cool logo on it, it's not Dex-cool. Stay away from Prestone Dex-cool substitute.

Link to comment
Share on other sites

the prestone has the dexcool logo now .... or if your worried about the prestone... the havoline brand dexcool is perfectly safe..... they make it for gm in the first place.... so my money is actuly in the Havoline

Link to comment
Share on other sites

sierra is still around.... it just isn't what they claimed and most people wont bother with it ... there is also prestone lox tox.... but as I said most people dont bother with it... I have sold a combined total of 3 gallons of the garbage in five years.....

Link to comment
Share on other sites

Yep, I highly recommend the Havoline, which is all I will use.

I don't trust the Prestone stuff. A couple years ago, it was NOT real Dex-cool. Maybe it is now, but I'm not sure I trust anything Prestone at all. It really didn't take any time at all before the Prestone green stuff ate through my head gaskets.

Link to comment
Share on other sites

so where would i find the dex-cool? either the GM or the Havoline?

i think i might have to take sometime in the spring and flush and go dex-cool.

 

so if there is this mud or sludge or phosphate build up what is the best way to remove it?

 

Monty

Link to comment
Share on other sites

so where would i find the dex-cool? either the GM or the Havoline?

i think i might have to take sometime in the spring and flush and go dex-cool.

 

so if there is this mud or sludge or phosphate build up what is the best way to remove it?

 

Monty

Wal-Mart carries the Havoline. Havoline makes the GM brand and the Havoline brand Dex-Cool.

FYI, Dex-Cool can be expensive, $5 - $15 a gallon depending on what store you find it at.

Link to comment
Share on other sites

I just sold my first gallon of Sierra antifreeze the other day, I dont know how they stay in business. Most people around here buy the green antifreeze to purposely get rid of stray pets! I've used green antifreeze in my 89 Cutlass and have never had a problem with head gaskets. Its got over 300K miles on it so I know it isnt hurting it. I'm building a 3.1L right now and when I was searching for heads to port I cam across some that had really bad corrosion in the water jacket. Thats probably just from someone neglecting to change there antifreeze though. I'll probably stick with the green in my new motor and use a anti-corrison additive.

Link to comment
Share on other sites

DEX-COOL Extended Life Anti-Freeze/Coolant.

By Scott Mueller

 

A revolutionary new type of long life engine coolant is now being used in ALL '96 GM cars and trucks except for Geo and Saturn. It is called Dex-Cool, and can be distinguished by it's unique orange color. Dex-Cool is manufactured for GM by Texaco Havoline, and is rated to last 100,000 miles or 5 years, whichever comes first.

 

Dex-Cool is an Ethylene Glycol based high performance coolant that contains unique corrosion inhibitors, which are different from anything else on the market. Dex-Cool is vastly superior to conventional coolants, which use silicates, phosphates, borates, nitrites, nitrates, and amine additives to eliminate corrosion. These additives are abrasive to water pump seals, and silicates are especially unstable and drop out of solution and form a gel after time. All of these conventional inhibitors deplete after a short time, which is why conventional coolant must be changed every year.

 

The unique corrosion inhibitor technology in Dex-Cool is based on the use of two organic acids, which are synergistic and combine to form carboxylates. Texaco refers to this as Organic Acid Technology (OAT), or Carboxylate Technology. The corrosion inhibitors used in Dex-Cool deplete very slowly thus eliminating the need for traditional additives, or frequent change intervals.

 

Note that contrary to what some may say (or write), you can indeed mix Dex-Cool and conventional coolant with no ill effects. However, if there is more than 10% of conventional coolant in the system this will reduce the concentration of the Carboxylate such that conventional coolants change intervals must be followed. In other words, if you mix it, you can't leave it in for 100,000 miles or 6 years, but instead should treat a mix just like conventional coolant and change it every year until the concentration of Dex-Cool is over 90%.

 

You can purchase Dex-Cool in gallons two ways, either under the GM part number (#12346290) which lists for $15.95 (about $10 with a discount), or under the Texaco-Havoline brand name at your local parts store. In my area, Pep Boys has it for $7.49. Currently in my area they are about the only place that has it, as it is still fairly new on the market.

 

Dex-Cool is extremely impressive compared to anything else currently available. Personally I am converting ALL of my vehicles over to Dex-Cool. For the Impala, I even installed the '96 Dex-Cool labeled reservoir cap and Dex-Cool "Notice" sticker for the radiator cover, exactly as they come on the '96 Impala. The Dex-Cool reservoir cap is available under #10285918 and cost me $3.29. The cap is functionally the same as the cap used in the '94 and '95 cars except for the sticker on the top which says to use only Dex-Cool, and which also has an orange dot in the middle instead of the green one found on the earlier caps. The Dex-Cool "Notice" sticker, which goes on the radiator cover, is available under #10283878. I don't know what it cost as my dealer did not charge me for it.

 

Since Dex-Cool is an Ethylene Glycol based coolant, it has the same excellent anti-freeze and heat transfer capabilities of other standard Ethylene Glycol based coolants. As such, Dex-Cool will perform as follows, which is identical to any other Ethylene Glycol based anti-freeze/Coolant:

 

Mixture (coolant/water) Freeze Point Boil Point

50/50 -34 deg F 265 deg F

60/40 -62 deg F 270 deg F

70/30 -84 deg F 276 deg F

 

Mixtures of less than 50% coolant or more than 70% coolant are not recommended. Note that these temperatures are in degrees Fahrenheit, and the boiling point temperature is dependent on a sealed cooling system with a 15 psi rated pressure cap.

 

Note that Dex-Cool differs from conventional coolants only in the additive package, not in the Ethylene Glycol base, meaning it provides the same anti-freeze and boil over protection as conventional high performance coolants, but also provides superior corrosion protection to all cooling system metals.

 

This higher level of performance is unlike coolants based on Propylene Glycol (i.e. Sierra brand), which are advertised as being environmentally more friendly than standard coolants, however which are also inferior when it comes to thermal transfer, anti-freeze and boil over capabilities. For example, Propylene Glycol based coolants freeze at -26 degrees Fahrenheit in a 50/50 mixture, compared to -34 degrees for the same mixture of Ethylene Glycol coolant. Also, despite their "green" claims, Propylene Glycol based coolant is indeed poisonous to humans and animals. GM reluctantly agrees that Propylene Glycol based coolants can be used in pre-'96 vehicles, stating that it will perform "adequately", but other manufacturers such as Chrysler indicate that the use of Propylene Glycol coolants are prohibited, and may void the warranty.

 

Due to the reduced thermal performance and conventional corrosion inhibitor packages, I do not recommend Sierra or any other Propylene Glycol based coolants. Since Dex-Cool is based on a superior Ethylene Glycol base, and all auto manufacturers specify Ethylene Glycol based coolant as recommended for their cooling systems, Dex-Cool can be used without problems in any automotive cooling system.

 

It might be difficult for some people to get excited about something like engine coolant , but Dex-Cool is the first revolutionary new product in this area in quite some time. In the future, Texaco Havoline expects other manufacturers to follow GM's lead and also switch to Dex-Cool for new vehicle factory fill.

 

Source: http://www.theherd.com/articles/dex_cool.html

For those who are unable to get to 60degreev6.com from work. (like me) :(

Link to comment
Share on other sites

somthing that may be of interest in all this....

 

 

while chrysler and ford have been using a orange antifreeze since around 1998... it is not dex cool.... and a recent tech bulliten that came into my work is saying that soon both advance and napa will be carring it... I have heard it works better then dex cool.... but I have not seen or nore heard any specs on it... I do know this, chrysler does not recomend using the dex cool as the organing compounds in it can cause thermostats to stick.... this might be do to chrysler using brass thermostats... but I will say this.... almost every performance thermostat is made of brass.. is the hypertech stats.. the robert shaw stats.... it maybe something we should look into.. I dont think gm's come with brass.. I think they are steel so it may not matter if any one has an info on this fill us in

Link to comment
Share on other sites

The new coolant that Daimler-Chrysler and Ford are using is Glysantin G-05. It's a HOAT coolant (Hybrid Organic Acid Technology). It has some silicates in it. Supposedly Mercedes did a study on OAT coolant and found cavitation around the water pump so they added silicates. They've been using this coolant since the late 80's.

Glysantin is also safer when mixed with the "old stuff". Dex-cool, when mixed with the "old stuff", will cause ACCELERATED aluminum corrosion so it's not recommended to mix it. The old stuff can be mixed with Glysantin with only a decrease in service life.

 

There should be no problems using Glysantin G-05 in a W-body, but I don't know that it's superior to Dex-cool either. From everything I've read, GM has been designing their water pumps to minimize cavitation for a number of years.

 

Here's a link to the new coolant (manufactured by Valvoline) http://www.valvoline.com/pages/products/product_detail.asp?Product=10

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...