Dex Cool sludge?
- Thread starter j_mac
- Start date
- Status
I have run new GMC vans for that many miles without ANY cooling system work of any kind with no issues.
Yes...
At 250K it probably already has made at least some sludge somewhere in the cooling system.
So will any other glycol based coolant or even water if enough miles are accrued.
Rickey.
At 250K it probably already has made at least some sludge somewhere in the cooling system.
So will any other glycol based coolant or even water if enough miles are accrued.
Rickey.
There are people who have run Dexcool over the recommended 5 years/150k miles and not had any problems. HDs run dexclone 300k miles then add a booster and run it 600k miles total regularly. Dexcool does not necessarily sludge due to just age but if you ran it much over 7 years/200k miles its inhibitors would start to deplete at some point and you would get corrosion.
In a system properly set up for Dexcool you would probably have to change the hoses, thermostat or waterpump before the coolant actually became depleted.
In a system properly set up for Dexcool you would probably have to change the hoses, thermostat or waterpump before the coolant actually became depleted.
Most dex cool is rated for 5 years or 150,000 miles. I have a 04 impala that has original dex cool in it, only 45,000 miles but 6 years old now. It has some sludge in the radiator and I need to do a coolant flush on it soon.
The problem with the Impalas is it has the cap on the radiator and tends to be somewhat prone to sludging from air more than the Dexcool being worn out. Plus both the 3.4 and 3.8 intake manifold gaskets tend to leak although the '04 and later are somewhat better.
What I do with them is either completely switch them to G-05 or Peak Global, or if I stay with Dexcool replace the cap with a Stant 10230/11230 spring-center cap, make sure the radiator is always full and fill the overflow bottle to full hot level. I also try to use Havoline Dexcool because it seems to be more sludge resistant than say Prestone dexcool/dexclone. I've seen that quickly sludge in a system that doesn't keep air out.
What I do with them is either completely switch them to G-05 or Peak Global, or if I stay with Dexcool replace the cap with a Stant 10230/11230 spring-center cap, make sure the radiator is always full and fill the overflow bottle to full hot level. I also try to use Havoline Dexcool because it seems to be more sludge resistant than say Prestone dexcool/dexclone. I've seen that quickly sludge in a system that doesn't keep air out.
Just do a drain and fill every other year and you will be fine.
Old coolant is not good. I have never seen coolant sludge or jell up unless the engine sits for long periods.
most likely it has sludged. easiest quick way to tell- remove the rez cap. if it smells like nasty fish hole
and there is build-up coating it......then, yah- you need to chemical flush, probably twice, and/or let the flush sit in there a bit (1/2-1 hour max) to break down the sludge and then a few water cycles.
Originally Posted By: mechanicx
I also try to use Havoline Dexcool because it seems to be more sludge resistant than say Prestone dexcool/dexclone.
I've heard the same about the Zerex stuff, even though I believe it is Havoline that actually manufactures the GM branded product.
I also try to use Havoline Dexcool because it seems to be more sludge resistant than say Prestone dexcool/dexclone.
I've heard the same about the Zerex stuff, even though I believe it is Havoline that actually manufactures the GM branded product.
Originally Posted By: dailydriver
Originally Posted By: mechanicx
I also try to use Havoline Dexcool because it seems to be more sludge resistant than say Prestone dexcool/dexclone.
I've heard the same about the Zerex stuff, even though I believe it is Havoline that actually manufactures the GM branded product.
Yes I think Zerex might be more sludge resistant because I think it has the IAT molybdate. I also believe Havoline supplies GM Dexcool. I've seen swithching from the GM/Havoline to the all makes and sludge happening quicker.
Originally Posted By: mechanicx
I also try to use Havoline Dexcool because it seems to be more sludge resistant than say Prestone dexcool/dexclone.
I've heard the same about the Zerex stuff, even though I believe it is Havoline that actually manufactures the GM branded product.
Yes I think Zerex might be more sludge resistant because I think it has the IAT molybdate. I also believe Havoline supplies GM Dexcool. I've seen swithching from the GM/Havoline to the all makes and sludge happening quicker.
yes, havoline, owned by chevron, makes the dex-cool for gm....how they passed off both the lies and liability off on gm for the law-suit, idk.... i think chevron should pony up for the damages....
Just do exactly what mechanicx and Boss302fan indicated and you will be fine ...Havoline Dexcool drained and refilled every other year , fill reservoir up to the Hot level (or even higher) to reduce air contact ...Five years running this program in my Buick and no sign of sludge what so ever !!
- Status
