GMW17707

Description / Abstract: GMW17707, 1st Edition, June 2017 - Ice Clunk

Introduction

Note: Nothing in this standard supercedes applicable laws and regulations.

Note: In the event of conflict between the English and domestic language, the English language shall take precedence.

Purpose. Provide a common global development and validation performance evaluation of a driveline system that can be subject to torsional impact loading. This procedure is run to evaluate the maximum axle torque after being subjected to severe loads resulting from multiple vehicle launches on ʺstep μʺ surfaces, i.e., surfaces that change from small frictional coefficient (μ), ʺlow μʺ, to large frictional coefficient, ʺhi μʺ. Reference GMW17196 and GMW17197 for further details.

Applicability. Vehicles that have driveline components at risk from impact loading due to driving events. For example, hybrid drive units with dampers between the engine and the drive unit. Continuously Variable Transmissions (CVT) or other transmissions that have higher inertia internal components may be considered for this test.

Remarks. This test was designed for evaluation of events that could result in high axle torques resulting from ice to dry pavement impacts that would be detrimental to the drive unit components. Hybrids have higher internal inertia than step gear transmissions due to electric motors. Damper failure modes are typically being addressed for overload, but other driveline components may be exposed to high dynamic torque events. The actual customer number of these maneuvers has not yet been determined