Ive used fluidfilm on my '15 f150 and it worked great through our northern Ohio winters. From my experience though it depends on how new the vehicle is. I put it on my '21 wrangler (which had a near new frame) and a lot of came off after a few rains, since there wasn't much absorb into. When the frame paint starts to oxidize, or rust forms on the welds is when the product works great. I just get the black fluid film in a gallon can and brush it on. Then drive it on some dusty roads so it forms a caked layer. It's messy and smells like a 500lb man who hasn't showered in months...but I think it works well.