Following are some criteria to help you judge how well your preventive maintenance (PM) inspections are saving your fleet money and downtime.
1. Reliability. What are your fleet's miles/hours to breakdown; mean time between failure by component; site-of-repair analysis of generated work orders; percentage of out-of-stock parts resulting from unplanned maintenance and percentage of missed deliveries due to vehicle breakdown?
2. Rate of Wear. Analyze oil, coolants and tires for wear.
3. Life Cycle Cost. Compare your vehicles' longevity and cost-per-mile/hour against maintenance, repair, fuel economy and residual/trade value of vehicles.
4. Repair Order Analysis. Determine the ratio of scheduled PM repair vs. demand or unscheduled repairs, site of repair (shop or road), extent of repair (i.e. bushing or casting) and failures after PM.