Originally Posted by YeloSno
WHAT!?! DO NOT USE PETROLEUM BASED PRODUCTS. THEY WILL DISINTEGRATE THE ORINGS, ANODIZING AND BOLT.
THAT and Vaseline costs more than air tool oil or lithium grease, which is more acceptable than a petroleum based product, but nonetheless could be replaced by a good quality oil from some company like AKALMP.
Vaseline (petrolium jelly) is what WGP recommended. And most o-ring are buna. They are widely used in industry from fruel to air tools and so on.
So if AKA oil isn't.....well....oil(petrolium). What is it?
To the OP.
Air tool oil, triflow or any light oil will be fine. I would not use a grease because it is thick and adds drag to the bolt.