I just replace my gaskets as needed. I inspect them pretty often. I do crack the hose fitting at the manifold often to vent air. I get rid of hoses periodically. If I have any doubts about a hose I toss it. Or cast it to the side to be used on a recovery machine. Nitrogen tank. Or whatever. Having Rock Solid hoses is very important to me. You have to know your manifold set is 100% good. Especially when pulling vacuum. I use the large 3/8 vacuum hose. A rubber gasket gets worn out and I can never replace it. I just can't get it out of there and get the new one in. So I end up tossing the hose. I go through a few of these hoses a year