What Kind of Lubricant for New Dump Valves ?

Stay away from petroleum based products like Vaseline on all new gaskets and o rings. They are not made of the same materials of old and will get brittle. We have an old undersink water filter that says to put Vaseline on the o ring. The new water filter for the trailer specifically states not to use Vaseline. Toilet seals get hard with Vaseline also. Plumbers grease or silicone paste are the preferred products by the mfgs.