Get used to it! We need those taps on our old trucks. When you do get to it, use some oil, penetrating or WD will work, proceed slowly, making sure your tap is perpendicular to your hole, turn it in a 1/4-1/2 turn then back it out the same. Then turn it in an additional 1/4-1/2 turn and back it out and repeat until it runs free. If you feel any hard resistance, stop and access the situation. The last thing you want to do is snap off a tap in the hole. Then you really created a mess.
Now, a 5/16-18 tap is a bit more rugged than say 1/4-20, and I don’t really foresee you breaking that tap just cleaning out your threads but I just want you to be aware of that possibility.
Last edited by Phak1; 03/31/2021 2:03 PM.