The results of hot-loosening tests according to VDA 235-203/VW 01131 and tightening and loosening tests on a tightening test rig are compared in this paper. The experiments are carried out from room temperature up to ϑ = 150 °C with variation of the dimension (M6 and M10), the bolt head geometry, the coating system of the bolt (zinc flake and zinc nickel as well as with and without top coat), the coating of the nut (bare, galvanized) and the type of counterpart (washer type HL and KTL (cathodic dip coating) steel bar).