Has anybody used old engine oil to treat plywood? I'm just about to renew the wooden panels and floor of my trailer with wbp plywood and I was about to go and buy some fence treatment, when my partner suggested using old engine oil instead. I know the plywood is water resistant, I just wanted to apply something so water doesn't cling to the wood. Could be a good idea but I'm concerned that the oil will have a detrimental effect on the the glue holding the plywood together. Any thoughts?