This paper presents a study of vibrations appearing in a vehicle in the process of its operation. The authors describe the primary source of the vibrations and their propagation in the entire structure. The observations were performed on the passenger cars with vari-ous gasoline and diesel engines. The aim was to examine the level of damping factor in the different locations in the car, precisely speci-fied for the purpose of this studies. The secondary goal was to develop an effective method of obtaining and analyzing signals generated during the engine operation. The chosen instrument was Laser Doppler Vibrometer (LDV), which is used as the non-intrusive measure-ment utensil to detect velocity variations in designated places. The signals are gathered and collected as group of sinusoidal characteris-tics in the time domain. In order to achieve specific information about every component of the original signal, the authors apply Fast Fourier Transform (FFT) as the analyzing method. It allows to distinct the basic sinusoidal characteristics in the frequency domain through the spectral analysis. Based on the results, the authors are able to distinguish the dominant modes from the complex signal and indicate their impact on the car.