In 1973 My Dad bought a new 3/4 ton Chevy and custom ordered a wooden bed floor. When it arrived it came with a metal bed floor. Dad specified it because his previous truck a 1966 ford f100 had its bed rust out. He was unhappy with the omission & the Chevy dealer said that Chevy no longer uses the wooden floors and that they had a new corrosion system that will prevent rust through. Dad wasn't convinced and wanted it undercoated. The Chevy dealer said he would do one better and got the truck zeibarted at his cost to make up for the mix up. Zeibart was a new process that drilled holes into body and sprayed a type of undercoating inside of all panels and under the body.It had little yellow plugs to cover the drilled holes. The bed and body of that truck rusted through in 3 years. Zeibart didnt stand behind it neither did Chevy. I live on Gulf coast of Texas steel rusts here. Galvanization, High Quality Stainless and aluminum do much better. Plastic needs UV inhibitors to survive our sun. I have used the spray in bed liners and the drop in plastic bed liners. I think the rubber bed mats work as well if not better than anything else.
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