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Corrosion Protection ‒ Proof That It Matters

Spending a little more time and money to prevent corrosion can drastically decrease your maintenance costs down the road, lower your overall total cost of own


Corrosion protection can feel like an upsell or an unnecessary item at the end of a long spec list. But the truth is, it can end up SAVING you from the cost of repairs or worse yet, early retirement for your buses. Corrosion is a big problem for many fleets because winter weather de-icing chemicals are now stronger than ever before. Road salt is a major corrosion culprit, but even worse are newer de-icing formulas, which include calcium chloride and magnesium chloride. After these de-icing agents settle on the body or up in the undercarriage of the bus, they slowly eat away at your investment, corroding the chassis, bumpers, or even the wiring of the bus. Corrosion protection stops that from happening.

Want proof?

A local Thomas Built dealer was able to see the effects of corrosion protection firsthand. Here are photos of the underbodies of two school buses in Maine, which were both running in the same climate for the same three years. The first image shows a bus that has a protective underbody wax coating. The bus in the second image does not have this undercoating protection.

The Federal Highway Administration estimates that damage from corrosion, like the bus in the second photo, costs around $276 billion each year for school transportation and trucking combined. Even a small chunk of that is an unnecessary expense for one bus, let alone an entire fleet.


Thomas Built corrosion protection

Thomas Built Buses takes steps to minimize corrosion on all of its buses. For example, Thomas is the only manufacturer who utilizes Galvalume® floor panels. Galvalume® steel, the preferred product for long-term resistance to atmospheric corrosion, outlasts a galvanized coating of comparable thickness and offers cut-edge protection. This protection protects against rust-staining along sheared edges, at scratches, and other imperfections in the coating. In addition to these floor panels, Thomas Built Buses has also eliminated the use of cold rolled steel in the bus structure, replacing it with galvanized steel. This includes the rear emergency doors, door jambs, and structural tubing. Galvanized steel provides superior protection from corrosive materials that slip inside a door or are tracked inside by passengers.

For key exterior and floor seating bolts, Thomas Built Buses utilizes best-in-class GEOMET® coatings to eliminate unsightly fastener corrosion. Finally, Thomas offers severe duty wiring harness options that utilize braided shielding to provide the highest available abrasion resistance and eliminates water traps that lead to wire corrosion from trapped salt water.

Additional corrosion protection options

In addition to standard corrosion protection, Thomas Built Buses also offers FleetShield™ corrosion protection as options, including Tuffcoat, EdgeCover and UnderGuard.

  • FleetShield TuffCoat is a durable, high-performance coating for bumpers and stepwells. TuffCoat provides a flexible, textured surface that reduces abrasions and dampens bus noise and vibration.
  • FleetShield EdgeCover is a clear, protective coating applied on top of standard paint. Also used in the luxury automobile industry, this durable, self-healing formula guards against corrosion and weather damage. It is applied to the perimeters of doors, wheelhouse fenderettes, lower skirt seams and even door hinges.
  • FleetShield UnderGuard is a durable, self-healing, high-performance undercoating applied to the underside of the body to protect against impact and corrosion.

If you didn’t spec your current bus with corrosion protection, there are a number of things that you can do today to keep your buses free of corrosion for as long as possible.

  1. Keep your buses clean. Be sure to wash buses often with a soap and water mixture to remove corrosion-causing agents. And, don’t forget about the undercarriage of the bus.
  2. If there is existing damage due to corrosion, repair and coat the area to prevent further spot corrosion that can spread.

Spending a little more time and money to prevent corrosion can drastically decrease your maintenance costs down the road, lower your overall total cost of ownership, and keep your bus on the road longer. If your fleet is experiencing corrosion issues, or if you are interested in preventing corrosion on your current fleet, talk to one of the Thomas Built dealers to learn how they can help.

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