Advocate III
I agree to remove the valve cores work well for airing up and down. My problem is I kept losing the valve cores. I did carry extra's, but the added stress was not worth it for me. The tool I mention does not weigh much and is compact. I believe if removing the valve cores works for you then all is good. There is no right answer.Remove valve core, count to whatever number is necessary to reach the desired pressure (make a cheat sheet), re-install valve core.
Removing the core to re-inflate will also speed the process regardless what kind of compressor you are using, (negligibly off a tank)
The first question I now ask myself is "What does it weigh?" and in virtually every instance less is better. A valve core wrench and some extra cores and caps might be 20 grams.
And yes, all of the benefits yielded in airing down the truck exist for airing down the trailer