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In February 2000, The Insurance Corporation of British Columbia (ICBC) completed the field testing and safety review of three new and two existing logging truck configurations. The three new configurations featured tridem-drive tractors pulling triaxle pole trailers (including a tridem drive straight truck) hauling long or short log loads. The British Columbia logging truck industry has been an enthusiastic proponent of tridem-drive vehicles and combinations for three main reasons: the configurations allow greater log load carrying versatility (easy switching between hauling a single long log load to multiple bundles of short log loads); higher payload capacity than the existing tandem drive tractor with triaxle pole trailer configuration; and, enhanced traction on steep off-highway grades than tandem drive tractors. ICBC developed a test plan to investigate the dynamic on-highway performance of the new configurations based on the results of a computer simulation.

In October 2000 ICBC oversaw the field testing of two new tridem-drive tractor/semi-trailer configurations: one tridem lowbed semi-trailer, and the other a tridem hayrack semi-trailer. The lowbed configuration was tested with the aim of establishing heavy-haul permit conditions, and the hayrack with the intention of introducing the configuration into the regulations as a new logging truck combination for the province. The British Columbia logging truck industry has been an enthusiastic proponent of tridem-drive vehicles because these vehicles allow greater versatility and payload capacity than the industry currently enjoys, and they provide greater traction than tandem-drive trucks on steep off-highway grades. ICBC drafted a test plan designed to evaluate certain key handling characteristics of the proposed configurations, particularly dynamic stability. ICBC selected an independent Professional Engineer to prepare a finalized test plan and carry out the testing.

A series of low-speed straightline braking tests with two test drivers were conducted on a performance-based brake tester as an exploratory study to examine the effect of tire rolling radius on a light-duty truck. Data collected by the flat plate brake tester and a load cell to measure pedal force were used to evaluate differences in the braking characteristics and rollover propensity of a 1992 four-wheel drive pickup. Tests were conducted with the test vehicle in the stock configuration with standard size tires and after it was equipped with aftermarket body and suspension lift kits and three incrementally larger size sets of radial tires. An analysis of test data indicated that the additional ride height and oversize tires had a profound effect on pedal force gain and significantly increased the rollover propensity of the altered vehicle.

Aftermarket body and suspension lift kits and oversize tires can be installed to improve step-in height, customize the appearance or enhance the utility of light-duty trucks (“raised vehicles”). The modifications could considerably increase the center of mass height, kingpin offset and tire rolling tire diameter - changes that could interfere with the integration of original components and subsystems. The alternations could lower braking efficiency, increase rollover propensity, affect steady-state handling and transient cornering behaviour, raise the risk of suspension and wheel component failures, and change the geometric alignment of primary energy-absorbing systems. A study was conducted to examine the effect oversize tires may have on the crash risk of raised vehicles.