This research aims to study and compare the test results obtained from the rolling resistance tester of automobile tires based on force method and torque method system. The four newly manufactured tires were sampled from two tire classes namely passenger car tires (Class C1) and light truck tires (Class C2). The tire rolling resistance test according to the international standard UN ECE Regulation No.117 was used as an important research process. The experimental work discovers that the rolling resistance of the same tire obtained from the test between the two different methods of testing machines was not more than 6 percent different. The testing results that used the torque method system calculation are high reliability because of the principle of calculation from the measurement value directly results in. and suitable for research testing. However the force method tester can perform more than a tire simultaneous test which is suitable for working in industrial applications where time is limited.

The objectives of this research are to study the rate of deterioration of tyre friction coefficient and investigate the quality of new and old tyres that are currently in use. A set of the rolling resistance testing was designed and set up to work with the single dynamometer according to speed 80 km/h tire load 4660 N and inflation pressure 30 psi. There were three tire samples new tire one year used tire and two year used tire to find the rolling resistance coefficients. The finding shows that the rolling resistance was inverse variation with tire aging. For instance the new tire (1st sample) had the highest rolling resistance on the other hand the two year used tire (3th sample) had the lowest rolling resistance. Moreover the rolling resistance coefficients were inverses variation with tire aging. Besides the one year used tire had the average of the decreasing rate of the rolling resistance coefficient at 0.03689 N/kN per a week while the two year had the average of the decreasing rate of the rolling resistance coefficient at 0.03671 N/kN per a week. Furthermore the result also revealed that the rolling resistance coefficients nonlinearly decreased comparing to the tire aging.