if it is proper PUL then go for it as it will realign the rods as Tory rightly says. The PUL is heated to make it waterproof so a boost to this will help.
I must say that if it's the stuff like Nature Babies wraps are made from then I've found washing with fabric conditioner is a better option as it coats the fibres, moreso the binding on the edges, and stops them from wicking.
It the waterproof is procare then I'm not sure, nor the comtex that wacky wraps uses.
I only tumble mine now if they need it but that's cause the drier is on it's last legs and keeps chewing things up LOL.