Optimizing a High-Variability, Low-Quantity Technology Refresh Vehicle Repair Line

This case describes lean and Six Sigma principles as they apply to a military vehicle repair and technology refresh line with high variability in vehicle induction conditions and low throughput quantities. Tactical mobility vehicles used within the Department of Defense (DOD) are inherently more expensive than vehicles in the commercial market. This is due to the DOD's requirements for durable performance, applications in complex operational environments, relatively low order quantities, and high operational availability. These requirements drive a duality between meeting performance thresholds and controlling costs. This duality creates a unique business case to repair and upgrade vehicles that does not exist in the commercial market. As an example, no company repairs a 2018 Toyota Tacoma and, in the process, upgrades it to a 2024 model year. We partnered with a member of the defense industry that operates a vehicle Repair and Technology Refresh (RTR) line that updates DOD vehicles to their most recent production year capability (production year 6, or PY6). Our team applied Lean Six Sigma principles and techniques, typically applied to high-volume, low-variability production lines, to decrease costs and improve the operational availability of these vehicles to the force.