Has any one heard any thing on anit freeze brake down

[mhbreed]

My neigbohr said he heard that the factory anti freese was breaking down after about 4 oil changes in the durmax and causing the pistons to get holes burned in them. Sounds like a ford diesel story to me, but though I would ask.

[Amianthus]

All engine coolants break down with use. The problem is that GM is gambling that the extended life coolant, propylene glycol (a.k.a. Dex-cool), will be able to survive long enough to make the warranty period. Other manufacturer's are doing the same thing, but it's still a gamble. I've seen the coolant in a buddy's Cadillac go straight to hades before 80,000. But our fleet vehicles run the same thing in our Pontiacs with not much problem. Although, we don't keep them 100,000 miles.
It seems to me that there are too many factors involved to rely on your coolant to last 100,000 miles. Cummins specifically forbids use of the stuff. I trust thier engine building know-how.
That being said, I think your neighbor is pulling your leg. 30,000 miles? C'mon. It could be true, but I doubt it. He's probably taking a single case of abuse and saying it is a design short-coming. My $.02.

[hoot]

I'd say play it safe and change at 50,000 miles. Can't hurt and it keeps things clean and fresh.

[More Power]

GM made the switch to the new orange colored organic acid based coolant (Texaco/Havoline Dex-Cool) in 1996 due to it's longer service cycle, longer water pump seal life, and a higher coefficient of heat transfer. This new coolant came with a 100,000 mile service cycle when originally introduced. Shortly thereafter, the industry upped the cycle to 150,000 miles since the coolant degradation and loss of additives didn't seem to be a problem. I've read where the industry (not necessarily GM) has begun recommending the average cycle life of this new orange coolant be increased to 250,000 miles and beyond in certain situations.

For all practical purposes, properly installing an organic acid based coolant is a "lifetime" service procedure, and won't require a routine flush for as long as you own your GM diesel. Longer seal life could also mean your water pump would last for as long as you own your diesel.

However, the recommended service cycle listed in your owners manual should be followed to ensure warranty coverage.

GM does not recommend installing an organic acid based coolant in systems with a copper/brass radiator because of a possible problem with lead corrosion. However, Prestone says their tests have shown no problem with lead corrosion and recommends the use of their organic acid based coolant in either copper/brass or aluminum systems.

We've been running Dex-Cool in the 6.5TD Power Project engine since January of 1999. During a thermostat change last january, we noticed that there is no corrosion inside the cooling system or other evidence of deterioration after 65,000 miles.

MP

[Black Dog]

Dex-Cool has been tagged with the nickname "Death-Cool" by some people. There have been a great number of problems in certain applications. For those who would like to know more, visit this link.

http://www.imcool.com/articles/antifreeze-coolant/dexcool-macs2001.htm

Enjoy!

[ 04-29-2002: Message edited by: Black Dog ]</p>

[mark45678]

I agree that its good for 50k or 3 years no more!!! it very common to see intake gaskets gone around coolant areas after 5 years ,WHY? thats why mine isnt going to be in that long!

[ 04-29-2002: Message edited by: mark45678 ]</p>

[More Power]

The story I wrote in 1999 on Dex-Cool was based largely on "NARSA Service Reports" volume 12, 5 dated September/October 1998. NARSA is an acronym for National Automotive Radiator Service Association.

Most of the above mentioned paper is centered on organic-acid coolants, and Dex-Cool in particular.

As mentioned previously, the DP's Power Project 6.5's thermostats were replaced in January of this year (to a lower temp rating), with about 65,000 miles and three years now on the engine and Dex-Cool. The inside of the radiator and rad cap were spotless, as was the inside of the thermostat housing.

The primary concerns mentioned for Dex-Cool that I've read include, 1- always ensure the cooling system is full. 2- Never mix different types/brands of coolant.

We'll continue to monitor the DP's project 6.5, and will report any change in the present cooling system condition.

MP

[ 04-30-2002: Message edited by: More Power ]</p>