In all fields, including here technical field, there will always be uncertainties [1,2]; from a quantity point of view uncertainties are a set of values that we can expect. To offer some examples in vehicle dynamic study there will always be uncertainties regarding weight value, rolling radius, rotational mass coefficient, drag coefficient, aerodynamic coefficient, front surface, transmission efficiency etc. . Throughout the paper we call on operations with values intervals and on differential equations with coefficients that have values within certain intervals. Using the well known differential equation for straight movement, certain parameters are analyzed regarding their influences onto the vehicle dynamic behavior. The theoretical achieved results are than compared with results that are reached through real test runs carried onto a vehicle that has gasoline injection, onboard computer, transducers and other built-in actuators. The data offered by these sensors is collected using a data acquisition system.