Isn't it Buicks one sells at the toilet after a hard nite of drinking!

I would perhaps replace all the studs to be on the safe side. I had the same sort of issue with my F150 and the other ones were stressed as well from the 2 broken studs. I knew that because I replaced two broken ones , tightened up the remaining ones and two more snapped off! Never had that happen before, and it has 6 studs!