Mobile mining equipment often operates in harsh environments characterised by remote locations and highly variable rock and operating conditions. This research explores the hypothesis that the failure behaviour of mining equipment is influenced by the physical properties of the ore and waste. We describe a method of examining this relationship via data mining on maintenance records and apply it to the hydraulic cylinders of two classes of earthmoving mobile equipment. Failure data for the analysis are drawn from maintenance work orders from 14 sites mining for haematite iron, nickel sulphide, and coking and thermal coal. The results show that the distributions of the estimated life parameters for hydraulic cylinders on earthmoving equipment are distinctly different for haematite iron, coal, and nickel sulphide sites. Analysis of the relationship between selected physical properties identified the influence of rock impact hardness number, abrasion index, and absolute hardness of the ore as significant factors for these hydraulic cylinders. Their effects are significant when parameters are considered in combination, for example, rock impact hardness number and abrasion index, and vary according to the cylinder type and asset class. The engineering implications of these results are considered with respect to known failure modes of the cylinders. © 2013 Mark Ho and Melinda Hodkiewicz.