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The distance, velocity and acceleration characteristics versus time of heavy trucks for use in accident reconstruction have been the subject of studies by Grimes and others. To date, the majority of the research has been done using tractor-semitrailers equipped with standard transmissions. In recent years, as transmission technology has improved, automated and automatic transmissions are becoming popular on North American roadways. A series of tests were performed to document the acceleration characteristics of two different tractors, a 2007 Volvo VNL and a 2011 Freightliner Cascadia, both equipped with automated transmissions towing both empty and loaded semitrailers. The vehicles were instrumented with a Racelogic™ VBOX III GPS data-logging device that measured speed. Other vehicle parameters were logged using the recording software manufactured for the specific engine manufacturer.

The Electronic Control Modules (ECM) installed on heavy truck engines record data during normal operation. While their primary purpose is to control the mechanical and electrical systems on the engine, they monitor other vehicle systems as well. Stored data from the ECM can be downloaded into reports that are useful for tracking fleet performance, scheduling maintenance or troubleshooting engine problems. Many of the current production heavy trucks also record event information that may be useful when analyzing or reconstructing accidents. It is not uncommon for a vehicle involved in a frontal accident to experience sudden decelerations and/or sustain damage to the coolant system or rupture the oil pan. Sustained data outside normal operating parameters from sensors on the engine will typically trigger the ECM to generate a fault code. On a Caterpillar ECM, a short event record called a Diagnostic Snapshot may also be generated with a fault code.