Coatings and corrosion
The core of each truck is its steel ladder frame chassis. Coatings make it last.
Regardless of the application, there ' s one design proven to provide the durability and strength truck fleets need: body-on-frame construction, built onto a steel ladder frame.
Ductility makes steel the ideal choice for a truck chassis. Steel is strong but flexible, returning to its original shape and structure without failing when under stress loads. But exposed and untreated steel is vulnerable to corrosion.
For mining, construction and agritransport operators, exposure to corrosive agents is higher than for an urban logistics truck travelling from a depot to delivery zones within greater Durban, Gauteng or Cape Town. That ' s why, to protect the integrity of a truck frame that ' s engineered to last for decades for severe-duty use, coatings matter so much.
Mixers, mines and coal
Concrete mixers have extreme corrosion exposure. Concrete droplets harden against the chassis, which creates two corrosion issues. It traps moisture, and when hardened and scraped away, concrete becomes abrasive, stripping protective coatings.
Cleaning concrete trucks with muriatic acid is another issue: although it ' s highly effective at removing hardened concrete, it also damages protective coatings.
South Africa has an enormous coal transport fleet, which is exposed to sulfur ' s corrosive effects. Coal mining zones aren ' t in deep desert areas with low ambient moisture and little annual rainfall.
Mpumalanga is one of the world ' s most valuable coal resources and a high-rainfall area. Transport operations in Mpumalanga are exposed to coal dust and moisture interactions, which can trigger sulfuric acid reactions that are highly corrosive to truck and trailer chassis and bodies.
The risk is that once a protective coating has eroded, especially around fasteners such as bolts or mounting brackets, corrosion can begin to weaken the steel. And that could be the start of an eventual frame crack or failure.
Preventing frame failure
Fleet buyers choose severe-duty trucks for construction and mining transport, based on the integrity of their frame rails and steel MPa strength rating. The integrity of an ultra-high-strength steel truck frame needs the most advanced corrosion protection coatings to withstand decades of severe duty-cycle use.
The best coating systems and products are application-specific, with chemistries and properties formulated for extremely corrosive conditions, like working in Mpumalanga ' s coal fields. Chassis protection should not be misunderstood as a cost. Fleet managers and maintenance teams need to consider the capex they ' ve invested in their trucks and trailers, as well as the potential cost of downtime due to frame failure.
Advanced urethane coatings or epoxy primers are not a cost. They protect the investment in trucks and trailers that do the most demanding jobs in South African transport, hauling coal, aggregate, and concrete to where it needs to be.
WORDS IN ACTION 12 APRIL 2026