Pedestal Wear Liner

A pedestal wear liner is a replaceable wear plate fitted in the pedestal jaw of a truck sideframe. It is part of the truck running gear and works directly with the roller bearing adapter beneath it.

Where It Sits

The pedestal is the inverted U-shaped opening at each end of a sideframe that straddles a wheelset bearing. The roller bearing adapter sits up inside this opening, and its top surface bears against the underside of the pedestal roof. The pedestal wear liner attaches to that pedestal roof, so it sits between the roof of the casting and the top of the adapter.

What It Does

Every time the truck warps to follow a curve, the adapter pivots and shifts slightly against the pedestal roof. Without a liner that rubbing would wear directly into the cast sideframe, gradually enlarging the pedestal opening and shortening the life of an expensive casting. The pedestal wear liner provides a hard, replaceable surface that takes this wear in place of the parent metal, prolonging the life of the sideframe.

Wear and Inspection

When the liner wears thin it is replaced, which restores the original pedestal fit far more cheaply than repairing or scrapping the sideframe. Pedestal and liner wear limits, and the condemnable conditions for an enlarged or worn pedestal, are defined in the AAR interchange rules and field manual.