The dynamic overturning response of combat vehicles and vehicles with electronic equipment shelters is of interest to the defense community since critical internal equipments can be damaged contributing to system malfunction and reduction of vehicle effectiveness which can jeopardize the mission. To overcome sensitivity of vehicles and associated equipments to overturning, the Army is actively engaged in a hardening program which will result in overturning mitigation. The current investigation is devoted to determination of overturning response and sliding motion of a specific Army vehicle i.e., HMMWV jeep and the S-250 shelter assembly subjected to side-on diffraction and drag loads from a 10 psi blast overpressure. Assemblage of aerodynamic box models has been configured to represent the two vehicles and the generated models have been run upto 1.6 s using MINITRUCK which is an implicit two-dimensional version of a flexible multibody dynamics code available at the Ballistic Research Laboratory. The study indicates large sliding and overturning response of these vehicles in the absence of restraints and demonstrates the need for stabilization and overturning mitigation using outrigger pairs, cables, guywires and other active devices attached to the vehicle body.