retreated pressure treated fence posts ??

I looked at a pasture for sale that had good looking pressure treated fence posts that were OLD. I questioned the seller and he said that the mops them with antifreeze from his vehicles. Is this helping or did he hit a batch of well treated posts? The soil here in florida really does a job on them.

It probably depends on how the original pressure treating was done--some treatment works a lot better than others. I doubt that putting antifreeze on treated posts helps them, rather I would suspect that the antifreeze might assist in washing off the treatment, especially in the wet Florida climate.

Can posts be retreated? Sure. When I was growing up we mostly fenced with split cedar posts. We always treated the posts, new or used, in barrels of used crankcase oil (probably with some "penta" in it). Before we used the treated posts, we would take them out of the soaking barrel and put them in an empty barrel supported about a foot off the bottom for the excess oil to drip off. Even so, the treated posts were messy and got you dirty handling them. But the preservative really worked. Lots of those posts that we put in the ground 50 years ago are still holding up fence just fine, although the tops of the posts have weathered badly and look pretty cruddy on that end. The parts of the posts in the ground still look about like when we buried them.

Unless the "treated" posts you are working with have rotted, I bet that soaking them in oil for a few months would make them good for a very long time. But to do the job right, you almost have to remove the posts and put them in a barrel. Just dumping oil on the ground might get you in trouble with the environazis and probably wouldn't help the fence much.

BTW, I still live on the property where I grew up and I still do some fencing. I very seldom use any posts except heavy weight metal T posts anymore. The T posts are so much less work to install and maintain than wood posts. I do occasionally put in railroad ties to reinforce a fence, but putting one of those in the way I like to takes several hours. On the other hand, I doubt that I will ever have to mess with that post again in my lifetime.

Good luck with your fence!

I have BTDT but used to use Creosote, but now use old engine oil, especially the tops.

Mark

Anti-freeze degrades quickly in the weather into harmless substances. So I doubt that it helps much.
Covering the tops of posts with metal caps really helps make them last longer.

There's treated wood and then some of it is faked. Some of it is just put in a open tank of solution long enough to make it green instead of being put in a pressure tank. I had some fence post that rotted off where it went into the ground. I cut them with a chain saw and found the solution barely went 1/4" into them. The older ones have arsenic in them which makes them much better. As far as maintaining them it would be better to treat them with Thompson Waterseal or equivalent.