Dexcool vs. the green stuff

[TJ Hopland]

I just met a man that has quite a nice collection of cars including some what I understand are rare Packards.  About 1/2 the cars are 1910-1940 the rest are 40-06. 90% of the collection gets driven at least a few time per yer.  Some are almost daily.  His mechanic said he runs Dexcool in everything because it holds up much better especially with the low miles.  He said the green stuff does not do well just sitting.  He said many of the other antique mechanics he talks to just run water and drain it for winter but he thinks thats harder on things like the block.

Thoughts?

[Otto Skorzeny]

Using water and draining it every year is about the worst thing you can do.

Water doesn't cause rust. It's the exposure to water, then the drying out that causes rust.

When those blocks are drained, all that wet cast iron is exposed to the air which will immediately oxidize.

Keeping the block filled with anything is better than exposing all that wet metal to the air every year.

[jeff1956]

dexcool works well but is really designed for aluminum engines and it is really only supposed to be ran in vehicles designed for it as it can eat through gaskets eventually. also if exposed to air it will form a brown sludge....ask any 00 up impala owner about the dexcool sludge that resulted from gm using regular gaskets and then when they failed due to dexcool they had to revise them and make themout of metal....i know i have an 04 impala....i wouldnt run that stuff in my 56....youll have issues with intake and head gaskets....if you dont like the green....there is a middle road the yellow prestone universal antifreeze..  DO NOT use dexcool in anything not designed for it unless youre looking for trouble.

jeff