The time has come to replace the kitchen faucet. The house was built in 1941 and the kitchen faucet is vintage wall-mount unit, metal faucet to metal piping. Bolts are easily accessible for mounting. I found a replacement wall faucet at Home Depot for $40.
So my question is, when watching my dad do this sort of thing when I was a kid, I seem to recall that there was something that he smeared on the threads to either improve grip or seal the connection or something like that. Am I right? If so, what is that stuff called? I think it was grey or something like that.