Where must hydraulic jacks be applied when servicing a rail car?

Hydraulic jacks must be applied on the truck's assembly, specifically at the designated jack pads. This is essential for several reasons. The truck assembly is designed to bear the weight of the rail car and provides a stable point for lifting. Positioning the jacks here helps ensure that the load is evenly distributed and minimizes the risk of structural damage to the car. It also enhances safety during the lifting process, reducing the likelihood of the car tipping or shifting unexpectedly.

Utilizing the outer edges of the car or the roof for jacking is not advisable, as these areas are not structurally reinforced to handle such loads and could lead to catastrophic failure. Likewise, placing the jacks under the center of the car does not offer the same level of stability as using the truck assembly, which can exacerbate safety hazards during service operations. Proper application of hydraulic jacks is critical for efficiently and safely performing maintenance on rail cars.