The Eaton Detroit Truetrac is a helical-gear style limited-slip differential that maximizes wheel traction and enhances driving and handling characteristics. OperationThe Truetrac operates as a standard (open) differential under normal driving conditions, allowing for unobtrusive operation. When a wheel encounters a loss of traction or the terrain changes, the helical-shaped gears mesh with increasing force, transferring torque to the high traction wheel until wheel spin is slowed or completely stopped. When the vehicle exits the low traction situation, the differential seamlessly resumes normal operation.PerformanceOperation of the Truetrac is smooth, quiet and automatic. The unit will engage without any driver action required. It also has no wearable parts and requires no maintenance, meaning less time in the garage and more time on the road.LubricationA quality petroleum GL5 rated (mineral) based oil is recommended. Synthetic oils may also be used if desired per axle manufacturer?s recommendations. Friction modifiers should not be used as they will decrease overall performance. Features Smooth and automatic engagement - no driver action needed Maintenance free, more time on the road Helical-style side and pinion gears Limited-slip operation