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Diesel Exhaust Fluid (DEF) systems are required to function in cold ambient temperatures below the freezing point of DEF. Manufacturers may demonstrate compliance by following an EPA guidance procedure described below [2], using whole vehicles at winter test sites at −18 deg C or lower. However, commercial trucks may have multiple variants with different DEF system layouts, so it is impractical to test every possible configuration. A climatic chassis dynamometer (CCD) can also be used for this test, but this is still expensive and time consuming, and does not address the problem of complexity. Instead, much time and expense can be saved by using simulation methods to identify worst case configurations, and to demonstrate with confidence that a limited number of tests will cover the whole possible range. This methodology can further be used to show that a range of vehicles can be represented with selected rig tests in a cold chamber.

Multileaf steel suspension springs are occasionally prone to failure through delayed hydrogen stress cracking, a brittle fracture that can occur even before the springs have been assembled into a vehicle. This failure mode is unusual, and problematic in respect of diagnosis and prevention. Jai Parabolic Springs Ltd (JPSL), the world's fourth largest leaf spring manufacturer, experienced early failures of this kind in springs produced for a truck vehicle program in 2005. The root cause was shown to be delayed hydrogen stress cracking, or hydrogen embrittlement. Tests were conducted to assess the conditions leading to this type of failure. Guidelines are presented that were developed, and proved in production, to prevent future recurrence.

Software has been developed to carry out data screening on steady-state engine dynamometer data, for application to gasoline engine mapping. The software carries out fully automatic data screening, capturing the expertise of experienced engineers, with benefits in labour saving, faster throughput and improved quality of result. The technical basis of the screening process is the local regression of test results, to ensure that the engine is displaying expected physical patterns of behaviour. Emissions and combustion pressure data are screened, as well as standard parameters such as fuel flow and torque. Automated screening makes it possible to cope with much faster rates of data acquisition without needing extra personnel, and without allowing the quality of result to be compromised. The programs are currently being used on a VAX mainframe, but they are also being incorporated into a PC-based system.