Complete data sets (i.e., when all components within a given sample have explicit failure mileage) are a rarity in automotive field data analysis. More typically, only a few components of the sample would fail and the respective failure mileage would be recorded. In order to correctly estimate the reliability function, however, one would need to know the (censoring) mileage on the non-failed components. The paper discusses a procedure to estimate the censoring mileage and, ultimately, the reliability function for a component of interest. The paper further argues that a similar procedure can be applied to the total time on test estimation in the reliability growth analysis.