This paper deals with the analysis of an approximation method based on Differential Quadrature (DQ) rules, that represent a well-known approach to solve numerically ordinary and partial differential equations. An explicit form of the approximate solution through DQ rules is here discussed. Such a form aims to overcome some shortcomings of the traditional DQ method for a class of delay differential equations, such as the modification of the partition in order to consider the delay. Several numerical examples are presented to show the effectiveness of the approach. The analysis is completed via the presentation of a possible application for car traffic modelled by delay differential equations.