Old salts

One of the biggest hazards on the highway in winter literally is on the highway: the chemicals used to treat roads for ice and snow. Exposure to these harsh chemicals has been associated with corroded brake shoes-a malady known as rust jacking. The rust on the shoe table expands and expands, and can eventually force the friction material off the shoe table. Then the lining may fracture, since the rivets restrain it from moving. These fractures typically appear on the edge of the lining in line with the rivets during an inspection.

In the past, rust jacking was limited to fleets travelling in areas of high sodium chloride use during winter conditions, or seaside fleets that picked up salt from the humid conditions. Today, some highway crews are laying down brine solutions of calcium chloride and magnesium chloride days before a storm to fight the effects of ice and snow. As vehicles travel through the solution, it becomes airborne.

Once it’s in the air, it’ll stick to undercarriage components and the corrosive condition will continue until you wash it off.

Brake manufacturers are working with a variety of coatings designed to inhibit corrosion on new and relined shoes. Haldex is applying such a coating to remanufactured shoes. When used in conjunction with Haldex Friction with Cross-Link Technology, the new Haldex brake shoe coating is guaranteed to protect against lining edge cracking from rust jacking-a definite out-of-service condition.

For information, contact Haldex at
1-800/643-2374 or visit www.hbsna.com.