This paper aims to determine whether modal testing can effectively identify looseness in a specific axially bolted joint. To investigate this, three different geometries are analyzed for two axially bolted beams with non-identical circular cross-sections. The modal properties of these beams are extracted using a commercial finite element software. Subsequently, experimental modal testing is conducted under free-free boundary conditions. To assess the effect of bolt looseness, the joint is tightened to three different torque levels, and modal testing is repeated. The results from these varying torque levels are compared to evaluate the looseness effect. Unfortunately, the primary modal parameters, such as natural frequency and mode shape, prove to be ineffective tools for detecting looseness, indicating that additional methods may be necessary. While the damping characteristics of each mode exhibit slight variations across different torque levels, these changes do not demonstrate a consistent or predictable pattern.