best way to treat wood truck and trailer floors?

[powerscol]

I just purchased a new PJ deck over. Dealer indicated to treat with with straight ATF - cheapest I can find - synthetic, even better. Apply with a pump up garden sprayer. He indicated it soaked in and dried better than anything he has used and he has been in business 40 years doing this.

 

[klm]

About 70/30 motor oil to diesel every year or so, used this for years on trailers.

 

[pmsmechanic]

I bought a new leftover 2013 PJ 22' tilt bed wood deck trailer a little over a week ago. The deck wood had dried out pretty good from sitting on the dealers lot for over a year. Last Saturday I used a 50/50 mix of used oil and diesel and applied it with a 3" brush. I laid it on heavy to let it soak in. Took about 2 gallons to coat the 22' deck. On Sunday I undercoated the trailer with spray on rubberized undercoating. That took about 10 cans. Best time to do that is when it's still new. While it was up in the air I got all the axle tag info for future reference when I need brakes.

I'm wondering about spraying the bottom with undercoating. Would that not hold the moisture in and help the wood to rot faster? It would be interesting to hear how it holds up.