Chacking Dexcool Antifreeze Mixture.....

Hi Everyone,

Does anyone remember the old squeeze-bulb-type antifreeze density measuring devices? You know, the ones with the floating plastic balls that tell you the glycol-to-water mix? Will one of those work (ie be acurate) with the new Dexcool antifreeze? Are there new versions of these gadgets for Dexcool?

Also, other than age, what are the criteria for flushing out the old Dexcool and replacing with a new batch? Clarity? Color? Smell? Taste?

Just kidding on that last one.....

With all of the problems that have been associated with Dexcool when it is allowed to mix with air at high temperatures, I'd rather not take the chance and have a service center accidentally introduce air into my presently-working cooling system. Besides, the cost of a fill and flush is in the $100 range...

I've got a '99 Blazer (4.3L) that only has 26K on it, so I am nowhere near the 100,000 mile mark, however that 5-year interval is coming up soon.....

Not Dead Yet

Reply to
NotDeadYet
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I had a similar situation with my low mileage 98 Buick. The Dexcool looked good but I did a drain and fill on the radiator only and installed a new radiator cap as a precaution of getting air into the system. That was last year and so far, so good. If you do that every couple of years I think you should be fine. BTW, I used the Prestone Dexcool product which cost about a third as much as the Dealership product. I also used distilled water to help prevent any contamination.

Reply to
Nelson Reifsnider

Drain, or syphon off a small amount of coolant, pour into paper cup, let stand overnight, pour cupfull back into recovery tank. Now look inside cup, if it's clean, than replacing * some * coolant sounds safe. If the bottom of cup has grit, so does your cooling system, and a flush is in order. I also use the Prestone equivilant, done so for several years in two Chevys. Nothing but praise for product, and yes, it tests with a conventional anti freeze floating balls tester

Reply to
451ctds

I've heard some GM mechanics recommending a flush and fill at 50,000 miles. Here is some info and while it is a few years old, it is still accurate.

Saved e-mail message From: Krisp_E snipped-for-privacy@msn.com(Rich=A0B) Date: Wed, Oct 15, 2003, 8:34am To: snipped-for-privacy@webtv.net Subject: DexCool MACS 2001: GM and Texaco "Bare All" about DEX-COOL=AE =A0 =A0 As in the past, the MACS 2001 Convention and Trade Show in Orlando provided some very interesting and helpful air conditioning information.=A0 However, the sleeper presentation at this show was not about refrigerant, but=97of all things=97engine coolant!=A0 (Sleeper does not refer to making you sleepy; it was anything but boring.) =A0 =A0 Marketing departments of major consumer goods manufacturers are known for their attempt to conceal even a shred of negative publicity about their products.=A0 You can't blame them; you do the same in your business.=A0 That's why it was refreshing to witness a candid GM/Texaco presentation about DEX-COOL coolant and its related field service problems.=A0 I give the big guys credit for even bringing up the subject because, well, let's face it, there are not a lot of kind words being spoken about this coolant at automotive service shops today.=A0 (Especially at radiator shops.) =A0 GM's Jay Dankovich and Equilon Enterprises' (Texaco) Stede Granger directed a 2-year study of thousands of DEX-COOL cooled vehicles.=A0 Armed with the results, they really didn't have anything bad to say about the coolant.=A0 In fact, they strongly defended the product's reputation.=A0 What they revealed to the audience is that specific models of GM vehicles have specific cooling system contamination problems.=A0 And essentially, that DEX-COOL is not the culprit! =A0 =A0 Their presentation started with a 14-minute video that is now being circulated to technicians at GM dealers nationwide.=A0 In the video, GM's trainers succinctly described the problems that have been found and the corresponding corrective actions to be taken by technicians. =A0 =A0 Suggestion.=A0 This video is a "must see" for all technicians considering themselves antifreeze/coolant experts.=A0 Without this information, your cooling system service knowledge of late model GM vehicles is severely limited.=A0 Seriously! =A0 Fortunately, you can buy the video for only $10 (plus S&H).=A0 Call MSX International of Auburn Hills, Michigan at 800-393-4831.=A0 Ask for the DEX-COOL Video: "Understanding Radiator Cap and Cooling System Contamination."=A0 Part number: RADCAPK.=A0 Immediately following this article is a report on this training video by John Brunner, recently retired GM field service representative. =A0 =A0 What was said at the presentation?=A0 Besides the video, Jay and Stede included their personal observations about the study.=A0 At the end, they fielded several questions from the audience.=A0 Here's a recap of their entire presentation. =A0 =A0

  1. Keep the cooling system filled.=A0 In fact, fill the reservoir bottle to "Hot" level when the system is cold.=A0 Problems arise when a system's coolant level is not maintained.=A0 (Fleet vehicles receiving regular maintenance, and with reservoirs kept slightly above normal, do not show signs of contamination.=A0 This even applies to the specific "problem" vehicles.) =A0 =A0
  2. The coolant problems found in this survey were caused by system contamination, and not due to the breakdown of DEX-COOL. =A0 =A0
  3. Check and keep the pressure cap clean and functioning.=A0 A contaminated and/or malfunctioning cap causes low coolant levels, which in turn causes overheating and a greater loss of coolant: the notorious vicious cycle.=A0 No matter what the vehicle, if the cooling system acts suspiciously, test the pressure cap. =A0 =A0
  4. On the ST vehicle models mentioned in the GM DEX-COOL video, you "must" replace all suspect radiator caps, especially those with a Drop-Center design, with a Stant Model 10230 or 11230 (Spring-Center type).=A0 (Just DO it.) =A0 =A0
  5. Make sure that the coolant is at a 50-50 mix.=A0 Often, the flush water was not being removed from the engine block.=A0 Consequently, when a 50-50 mix is added to the system the resultant mixture could approach
30-70.=A0 Like any fluid that has been diluted beyond its recommended levels, the lowered level of inhibitors will not be able to protect the coolant system effectively.=A0 Low levels of inhibitors can cause pitting on aluminum surfaces and general corrosion of cooling system metals. =A0 =A0
  1. A safe method of achieving a true 50-50 mix is to first determine the actual capacity of the system (use the owner's manual).=A0 Then add 50% of "that" amount of undiluted DEX-COOL (or any coolant), and top it off with water. =A0 =A0
  2. Mixing a "green" coolant with DEX-COOL reduces the batch's change interval to 2 years or 30,000 miles, but will otherwise cause no damage to the engine. In order to change back to DEX-COOL however, the cooling system must first be thoroughly drained and flushed. =A0 =A0
  3. Bacteria cannot live in a hot, Ethylene Glycol environment and is therefore not a threat to DEX-COOL. =A0 =A0
  4. While there have been intake gasket failures on CK Series, V8 powered vehicles for various reasons, DEX-COOL has never been found as a cause. =A0 =A0
  5. Use a refractometer to check the condition of DEX-COOL.=A0 Its inhibitor package is strong enough that if the batch still provides proper freeze protection, it is probably still providing proper corrosion protection as well. =A0 =A0
  6. DEX-COOL can handle the minerals in hard water better than silicated conventional chemistry coolants.=A0 Drinkable water is suitable for top off. =A0 =A0
  7. In ST Blazer applications where the radiator cap is mounted at an angle to the ground, the vehicle is more susceptible to radiator cap contamination and its related problems.=A0 The Stant 10230 is a wise choice for these vehicles. =A0 =A0
    formatting link
    =A0 =A0 Soon you will be able to check in with "current" radiator and a/c industry vendors on the web at:
    formatting link

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% There are two classes of pedestrians in these days of reckless motor traffic - the quick and the dead. ~ Lord Dewar 1933 ~

Climbing into a hot car is like buckling on a pistol. It is the great equalizer. ~ Henry G. Felsen 1964 ~

Reply to
Rich B

Saved e-mail message

From: Krisp_E snipped-for-privacy@msn.com(Rich B) Date: Wed, Oct 15, 2003, 8:34am To: snipped-for-privacy@webtv.net Subject: DexCool MACS 2001: GM and Texaco "Bare All" about DEX-COOL®

As in the past, the MACS 2001 Convention and Trade Show in Orlando provided some very interesting and helpful air conditioning information. However, the sleeper presentation at this show was not about refrigerant, but-of all things-engine coolant! (Sleeper does not refer to making you sleepy; it was anything but boring.)

Marketing departments of major consumer goods manufacturers are known for their attempt to conceal even a shred of negative publicity about their products. You can't blame them; you do the same in your business. That's why it was refreshing to witness a candid GM/Texaco presentation about DEX-COOL coolant and its related field service problems. I give the big guys credit for even bringing up the subject because, well, let's face it, there are not a lot of kind words being spoken about this coolant at automotive service shops today. (Especially at radiator shops.)

GM's Jay Dankovich and Equilon Enterprises' (Texaco) Stede Granger directed a 2-year study of thousands of DEX-COOL cooled vehicles. Armed with the results, they really didn't have anything bad to say about the coolant. In fact, they strongly defended the product's reputation. What they revealed to the audience is that specific models of GM vehicles have specific cooling system contamination problems. And essentially, that DEX-COOL is not the culprit!

Their presentation started with a 14-minute video that is now being circulated to technicians at GM dealers nationwide. In the video, GM's trainers succinctly described the problems that have been found and the corresponding corrective actions to be taken by technicians.

Suggestion. This video is a "must see" for all technicians considering themselves antifreeze/coolant experts. Without this information, your cooling system service knowledge of late model GM vehicles is severely limited. Seriously!

Fortunately, you can buy the video for only $10 (plus S&H). Call MSX International of Auburn Hills, Michigan at 800-393-4831. Ask for the DEX-COOL Video: "Understanding Radiator Cap and Cooling System Contamination." Part number: RADCAPK. Immediately following this article is a report on this training video by John Brunner, recently retired GM field service representative.

What was said at the presentation? Besides the video, Jay and Stede included their personal observations about the study. At the end, they fielded several questions from the audience. Here's a recap of their entire presentation.

  1. Keep the cooling system filled. In fact, fill the reservoir bottle to "Hot" level when the system is cold. Problems arise when a system's coolant level is not maintained. (Fleet vehicles receiving regular maintenance, and with reservoirs kept slightly above normal, do not show signs of contamination. This even applies to the specific "problem" vehicles.)

  1. The coolant problems found in this survey were caused by system contamination, and not due to the breakdown of DEX-COOL.

  2. Check and keep the pressure cap clean and functioning. A contaminated and/or malfunctioning cap causes low coolant levels, which in turn causes overheating and a greater loss of coolant: the notorious vicious cycle. No matter what the vehicle, if the cooling system acts suspiciously, test the pressure cap.

  1. On the ST vehicle models mentioned in the GM DEX-COOL video, you "must" replace all suspect radiator caps, especially those with a Drop-Center design, with a Stant Model 10230 or 11230 (Spring-Center type). (Just DO it.)

  2. Make sure that the coolant is at a 50-50 mix. Often, the flush water was not being removed from the engine block. Consequently, when a 50-50 mix is added to the system the resultant mixture could approach
30-70. Like any fluid that has been diluted beyond its recommended levels, the lowered level of inhibitors will not be able to protect the coolant system effectively. Low levels of inhibitors can cause pitting on aluminum surfaces and general corrosion of cooling system metals.

  1. A safe method of achieving a true 50-50 mix is to first determine the actual capacity of the system (use the owner's manual). Then add 50% of "that" amount of undiluted DEX-COOL (or any coolant), and top it off with water.

  2. Mixing a "green" coolant with DEX-COOL reduces the batch's change interval to 2 years or 30,000 miles, but will otherwise cause no damage to the engine. In order to change back to DEX-COOL however, the cooling system must first be thoroughly drained and flushed.

  1. Bacteria cannot live in a hot, Ethylene Glycol environment and is therefore not a threat to DEX-COOL.

  2. While there have been intake gasket failures on CK Series, V8 powered vehicles for various reasons, DEX-COOL has never been found as a cause.

  1. Use a refractometer to check the condition of DEX-COOL. Its inhibitor package is strong enough that if the batch still provides proper freeze protection, it is probably still providing proper corrosion protection as well.

  2. DEX-COOL can handle the minerals in hard water better than silicated conventional chemistry coolants. Drinkable water is suitable for top off.

  1. In ST Blazer applications where the radiator cap is mounted at an angle to the ground, the vehicle is more susceptible to radiator cap contamination and its related problems. The Stant 10230 is a wise choice for these vehicles.

formatting link

Soon you will be able to check in with "current" radiator and a/c industry vendors on the web at:

formatting link

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% There are two classes of pedestrians in these days of reckless motor traffic - the quick and the dead. ~ Lord Dewar 1933 ~

Climbing into a hot car is like buckling on a pistol. It is the great equalizer. ~ Henry G. Felsen 1964 ~

Reply to
stuart8181

Hmm! you must be refering to the shells used to clean gas turbines. The pellets that GM uses in certain older vehicles actually do work for those vehicle/engine combinations.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% There are two classes of pedestrians in these days of reckless motor traffic - the quick and the dead. ~ Lord Dewar 1933 ~

Climbing into a hot car is like buckling on a pistol. It is the great equalizer. ~ Henry G. Felsen 1964 ~

Reply to
Rich B

Those antifreeze testers should work the same on any glycol-based antifreeze - they're just measuring the glycol content, the only differences between DEX-COOL and conventional antifreeze are in the additives which are a small percentage of the volume of the coolant.

Reply to
Robert Hancock

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