A new method for correlation test was presented to study the reliability of a heavy duty vehicle, and the method can combine the real customer usage with the enhancement test on proving ground, and avoid the test blindness. Aiming at the data that were tested on the typical pavements of the customer and enhancement roads of proving ground, the rain-flow counting method was used to obtain the load distribution matrixes , according to the correlation equation, the cumulative fatigue damage and loading spectrums of the 90% customer and proving ground were optimized and calculated. Through the correlation analysis, the pavements enhancement coefficient and the reliability test specifications were obtained. The test results indicate that the new specifications can predict the potential failures of the load carrying structures quickly, shorten the test cycles.