Originally Posted By: ls1mike
Originally Posted By: mechanicx
If you have the pressure cap on the radiator, like many Grand Prixs do, then with Dexcool you have to be extra cautious with radiator caps, fluid level and that the reservior hose to the radiator is sound. I don't trust Dexcool in an application with the cap on the radiator, but otherwise i think it works fine.
I don't think the 3.8 overall had the lower intake gasket problem like the 60 degree V6 did. 3.8 had more of an upper intake gasket/manifold problem and that's probably why the S/C ones didn't leak as much as the NA.
I think you are right to a point. The F-body and Corvette with the LS1 have a Radiator cap and do not have the problems of the cars that have coolant run through the intake. I have had 3 LS1 F-bodies the 98 and 01 I had, had over 150,000 miles a piece on them when I got rid of them and they all had Dex Cool (The Trans Am only has 54,000 miles on it), but the whole system is Aluminum. Seems to me the LSX engines don't have any problem with it, as do the rest of the cars that have a system where the coolant only touches Aluminum heads, blocks, water pumps and radiators. The LSX Trucks, the 4.8, 5.3, 6.0 have Aluminum heads but cast iron blocks. Not sure what year it started but those trucks have no radiator cap (maybe 04?). Not sure if that has been discussed before.
I think that maybe the DEX COOL and the Cast Iron parts don't play together well either.
Yes I do agree with you that the Dexcool really played havoc with the iron engines with the cap on radiator much moreso than the aluminum engines even with a cap on radiator. The thing is though even with an iron engine it was air as the culprit more so than just iron. Many iron block/aluminum head engines with the cap on the reservior faired fine with Dexcool. With a 3.8 Grand prix or Impala etc, you have all the conditions for a problem, all iron engine and the cap on the radiator.
I also believe on the 3.8 was the upper intake manifold and the EGR passage as you mentioned.
Originally Posted By: mechanicx
If you have the pressure cap on the radiator, like many Grand Prixs do, then with Dexcool you have to be extra cautious with radiator caps, fluid level and that the reservior hose to the radiator is sound. I don't trust Dexcool in an application with the cap on the radiator, but otherwise i think it works fine.
I don't think the 3.8 overall had the lower intake gasket problem like the 60 degree V6 did. 3.8 had more of an upper intake gasket/manifold problem and that's probably why the S/C ones didn't leak as much as the NA.
I think you are right to a point. The F-body and Corvette with the LS1 have a Radiator cap and do not have the problems of the cars that have coolant run through the intake. I have had 3 LS1 F-bodies the 98 and 01 I had, had over 150,000 miles a piece on them when I got rid of them and they all had Dex Cool (The Trans Am only has 54,000 miles on it), but the whole system is Aluminum. Seems to me the LSX engines don't have any problem with it, as do the rest of the cars that have a system where the coolant only touches Aluminum heads, blocks, water pumps and radiators. The LSX Trucks, the 4.8, 5.3, 6.0 have Aluminum heads but cast iron blocks. Not sure what year it started but those trucks have no radiator cap (maybe 04?). Not sure if that has been discussed before.
I think that maybe the DEX COOL and the Cast Iron parts don't play together well either.
Yes I do agree with you that the Dexcool really played havoc with the iron engines with the cap on radiator much moreso than the aluminum engines even with a cap on radiator. The thing is though even with an iron engine it was air as the culprit more so than just iron. Many iron block/aluminum head engines with the cap on the reservior faired fine with Dexcool. With a 3.8 Grand prix or Impala etc, you have all the conditions for a problem, all iron engine and the cap on the radiator.
I also believe on the 3.8 was the upper intake manifold and the EGR passage as you mentioned.
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