draining dexcool

[steiner43511]

well my warranty has come up and i am going to drain the dexcool out of my 97 6.5 turbo diesel gmc truck. am planning on putting cheap supertech wally world green stuff in its place, but am not sure if this is a good idea after reading in this forum. what is a good cleaner/flush to use for a diesel? what kind of antifreeze do i need to look at for a diesel or will this supertech stuff work? do you really need distilled water? my radiator is large and that would take a lot of distilled water. and what would be the best way to get all of the dexcool out?

 

[vettenuts]

Interesting, I have changed all my vehicles from "green" to Dexcool and have been very impressed with the performance. Have you read the GM/Texaco paper on the sludging that was taking place and is so famous. Primary reason is low coolant or improper mix. I have also looked into my radiator and engine block with a boroscope and found them to be incredibly clean with the Dexcool.

 

[Ed]

Big Mistake to use ordinary cheap automotive anti-freeze in a diesel engine. All of the major antifreeze mfrs produce a diesel formulation in addition to the automotive blends.. Problem is that the true diesel formulations are a bit hard to find at the local autoshop. Zerex G-05 is advertised as being suitable for diesels and is fairly easy to find. Thats what I would use.
The severe internal vibrations set up by compression ignition engines actually causes cavitation in the coolant. This is a very violent and destructive phenomena. It's actually pockets of vaccuum forming and than having the coolant collapse into those pockets with an extreme amount of energy. This results in a form of corrosion internal to the engine block. Diesel formula A/F has special additives to deal with this.
It doesn't pay to try to save a few bucks on antifreeze when an expensive diesel engine might be damaged.
Ed

 

[steiner43511]

thanks ed. is this zerex compatible in gm trucks? and is it compatible with dexcool because i probably won't be able to get all the dexcool out?

 

[JohnBrowning]

I would not worry about the Dex-Cool. I would use a Dex-Cool COmpatible coolant. Mix it 50/50. Distilled water is very cheap you can normaly buy it for $1-$1.25 a gallon. I would not risk an expensive radiator, liners,or water pump to tap or well water! If you mix 50/50 and top off water as needed Dex-Cool works great.

If you do put non-dex cool in use a low silicate formula at least. Big lots had some Cat precharged long life coolant on sale.

 

[Jelly]

quote:

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Originally posted by JohnBrowning:
Distilled water is very cheap you can normaly buy it for $1-$1.25 a gallon. I would not risk an expensive radiator, liners,or water pump to tap or well water!

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Neither would I...but where the heck are you buying your distilled water??

It's only 50-60 cents!

 

[ekpolk]

quote:

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Originally posted by Jelly:

quote:

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Originally posted by JohnBrowning:
Distilled water is very cheap you can normaly buy it for $1-$1.25 a gallon. I would not risk an expensive radiator, liners,or water pump to tap or well water!

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Neither would I...but where the heck are you buying your distilled water??

It's only 50-60 cents!

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Undoubtedly in the "convenience" store that's a half-mile from my house, which also sells no-name SG oil for $2.50 per qt. . .

 

[Hankrr]

quote:

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Originally posted by JohnBrowning:
If you do put non-dex cool in use a low silicate formula at least. Big lots had some Cat precharged long life coolant on sale.

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How do you know if it's low silicate or not? I'm wondering because my Honda manuel also says to use one with low silicate's. It's says silicate's can cause early leaks around the water pump seals or something.

Does anyone know if the Prestone 5/150 Dexcool equivilent is low silicate?

 

[tmorris1]

I think the DexCool problem is blown way out of proportion. I don't know anyone that has had problems using it. From what I understand the problems seem to come from people running the system low and getting air in the system.

 

[Ed]

G-05 is sufficiently compatible with Dex-Cool that the small amount of Dex-Cool remaining in the system is of no consequence. I used Prestone long life(roughly the same as Dex-Cool) in my 79 Toyota truck since it came on the market and it works great.
I heard somewhere that the a lot of the problems with Dex-Cool were largely confined to the actual GM product made by Texaco and that no such problems were evident with the Prestone version. Probably an urban legend but I also heard that GM now buys their Dex-Cool from Prestone instead of Teaxaco. Prestone long life , like Dex-cool is ZERO silicate. If Dex-Cool was the original product in your vehicle, you should have no problem using Prestone Long Life. Zerex also makes a Dex-Cool equivalent (Not G0-5) that would be suitable but it's a little harder to find.
Ed

 

[Thatwouldbegreat]

Does your diesel engine need an anti cavitation additive?

I switched many Ford Power Stroke diesels to Shell Rotella Extended Life Coolant [ELC] to reduce service and avoid having to add Ford's anti cavitation product.

Dex Cool does seem to cause problems in older vehicles converted to Dex Cool.

The Dex Cool cleans the silicate deposits and wipes out water pump and radiator pressure caps.

The pressure caps become one way valves and that only lets the coolant.

Air gets into the system, even though the overflow tank is full.

Then the Dex Cool breaks down [turns to mud or becomes very acidic] and the head gaskets fail from chemical and thermal stress.

I wonder if the best course of action is to continue to replace the factory fill coolant with the identical fluid?

 

[Thatwouldbegreat]

I guess I should say that the Halvoline Dex Cool caused problems since that is the Dex Cool that failed on 5 vehicles that I maintain.

 

[Stinky Peterson]

The Shell Rotella Extended Life coolant is essentially the same coolant as the Dexcool except it has a nitrite additive.