Non–uniform gear wear changes gear topology and affects the noise performance of a hypoid gear set. The
aggregate results under certain vehicle driving conditions could potentially result in unacceptable vehicle
noise performance in a short period of time. This paper presents the effects of gear surface parameters on
gear wear and the measurement/testing methods used to quantify the flank wear in laboratory tests. Gear
tooth profile, transmission error, gear tooth surface finish determined by cutting, and geartooth surface finish
determined by other processes are the factors considered in this paper. The measurements include
transmission error, coordinate measurementmachine (CMM), pattern rating, and surface roughness pre and
posttest. ASTM L–37 based dynamometertestprocedureis adopted forthewearstudywith good correlation
to field samples. The laboratorytest samples are established based on design ofexperimentconsidering the
controlled factors. The effects and interaction between controlled factors provided theinformation forproduct
improvement. The action resulted from this studyis anticipated to significantlyimprove product reliabilityand
customer satisfaction.