Dex-Cool in the Uplander
bobancle
04-16-2009, 01:02 AM
I've been reading all this scary stuff about Dex-Cool. I know there is Dex-Cool in the Uplander. Does anyone know if it has received any modifications to prevent the problems with Dex-Cool from happening. I have seen advice out there to flush and replace it every two years but I'n not sure if agree with that. Has anyone replaced the Dex-Cool with something. Why does GM insist on using this stuff, I don't see a single benefit that justifies the problems that have occurred.
'97ventureowner
04-16-2009, 01:15 AM
The problem was not in the Dex Cool itself, rather poor gasket design and/or materials. In mid 2002 GM released a revised edition of the intake gaskets that pretty much took care of the issues on the 3.4s in the vans that preceded the Uplander. The Uplander, however does not have the 3.4 engine but rather the 3.5 and 3.9 which do not have any of the issues. On some other vehicles that experienced problems it was also revealed that other problems existed which compounded the issue such as air infiltration into the cooling system, or the mixing of another type of coolant with the Dex Cool, or poor maintenance of the cooling system.
Dex Cool is a modern replacement for the old standby green coolants of the 20th century. It is designed with the proper protection package to work with the different compositions that make up today's engines. Proper and periodical maintenance is a must ( as well as any other system or lubricant in an engine. ) I have used Dex Cool over 10 years without any major issues and change out the coolant roughly every 40,000 miles or 3 years, which basically was the same recommended change interval for the older coolant. I think we can rest assured that the issues that plagued the older vans won't present themselves in the 2005+ GM U body vehicles. It took GM a long time ( too long in many people's opinion ) to take action and develop ways of working with the coolant and having the proper materials and designs to mitigate any problems to get to this point.
Dex Cool is a modern replacement for the old standby green coolants of the 20th century. It is designed with the proper protection package to work with the different compositions that make up today's engines. Proper and periodical maintenance is a must ( as well as any other system or lubricant in an engine. ) I have used Dex Cool over 10 years without any major issues and change out the coolant roughly every 40,000 miles or 3 years, which basically was the same recommended change interval for the older coolant. I think we can rest assured that the issues that plagued the older vans won't present themselves in the 2005+ GM U body vehicles. It took GM a long time ( too long in many people's opinion ) to take action and develop ways of working with the coolant and having the proper materials and designs to mitigate any problems to get to this point.
spike88
04-16-2009, 10:22 AM
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I agree with '97ventureowner.
My Auto mechanic also told me the 1st generation of Dex-Cool formula (when it first came out) was very sensitive stuff. And, it was also too high in acid / cleaning "ability". It loved eating gaskets (especially weaker designed gaskets within early 3.4L engines) and it loved getting gummed up from air exposure as well. The newer (today's) Dex-Cool formula is much, much better. It takes more beating and doesn't "eat away" at weaker internal engine components - like gaskets. To me, this makes sense. Many companies make better and better formulas - as time goes on.
My certified mechanic also recommended that Dex-Cool be replaced every 3 years (even if their bottle recommends `only every 5 years`). Change every 3 years and its "no worries". If wondering, I changed my vehicle's Dex-Cool every 3 years. Never had a problem with "gum up" or gasket eating. And if wondering, I still have a 2003 3.4L engine (in my other "run about" GM vehicle) running Dex-Cool. That engine still runs great today. For me, I leave "new formula" Dex-Cool formula in my engines and change every 3 years as well.
BTW: When I get my vehicle's rad's Dex-Cool fluid changed (every 3 years), I also change its transmission fluid and its drive axle fluids as well. Many poeople often forget to change these "sensitive / high RPM area" fluids on a regular basis as well.
Hope this helps...
.
I agree with '97ventureowner.
My Auto mechanic also told me the 1st generation of Dex-Cool formula (when it first came out) was very sensitive stuff. And, it was also too high in acid / cleaning "ability". It loved eating gaskets (especially weaker designed gaskets within early 3.4L engines) and it loved getting gummed up from air exposure as well. The newer (today's) Dex-Cool formula is much, much better. It takes more beating and doesn't "eat away" at weaker internal engine components - like gaskets. To me, this makes sense. Many companies make better and better formulas - as time goes on.
My certified mechanic also recommended that Dex-Cool be replaced every 3 years (even if their bottle recommends `only every 5 years`). Change every 3 years and its "no worries". If wondering, I changed my vehicle's Dex-Cool every 3 years. Never had a problem with "gum up" or gasket eating. And if wondering, I still have a 2003 3.4L engine (in my other "run about" GM vehicle) running Dex-Cool. That engine still runs great today. For me, I leave "new formula" Dex-Cool formula in my engines and change every 3 years as well.
BTW: When I get my vehicle's rad's Dex-Cool fluid changed (every 3 years), I also change its transmission fluid and its drive axle fluids as well. Many poeople often forget to change these "sensitive / high RPM area" fluids on a regular basis as well.
Hope this helps...
.
bobancle
04-17-2009, 11:24 AM
IF you need to top the DexCool do use the Officiall GM labelled stuff from the dealer or do use one of the 3 makers of DeX-cools stuff like Zerex Dex-Cool for example.
spike88
04-17-2009, 12:06 PM
IF you need to top the DexCool do use the Officiall GM labelled stuff from the dealer or do use one of the 3 makers of DeX-cools stuff like Zerex Dex-Cool for example.
For my "brand new" 2009 Montana with original GM DexCool fluid, I would "top it off" with original GM DexCool - purchased from my local GM dealer. Ya. Little more expensive (being a dealer) but the GM Dexcool (with my confirmed purchase receipt) keeps my new van's warranty good.
For my 2003 "run about" GM 3.4L engine, I visit my local auto mechanic. He installed non-GM Dexcool stuff in its RAD last spring. If this fluid needs topping off, I simply ask him to "top it off" - while getting an engine oil / filter change at the same time. Thus, I know he's using the same DexCool formula (non-GM formula) as before.
Where possible, I do NOT mix GM Dexcool and non-GM Dexcool formulas.
This approach works for me....
.
For my "brand new" 2009 Montana with original GM DexCool fluid, I would "top it off" with original GM DexCool - purchased from my local GM dealer. Ya. Little more expensive (being a dealer) but the GM Dexcool (with my confirmed purchase receipt) keeps my new van's warranty good.
For my 2003 "run about" GM 3.4L engine, I visit my local auto mechanic. He installed non-GM Dexcool stuff in its RAD last spring. If this fluid needs topping off, I simply ask him to "top it off" - while getting an engine oil / filter change at the same time. Thus, I know he's using the same DexCool formula (non-GM formula) as before.
Where possible, I do NOT mix GM Dexcool and non-GM Dexcool formulas.
This approach works for me....
.
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