[Noxzema]

i have same rust. I now coat the whole undercarriage with transmission fluid maybe every 6 months. i use my paint spray gun hooked up to my compressor, fill up the paint container with dextron and go to town! i have read this works as a rust prevention coating. I use my powerwasher to blast away the dust and dirt that attracts to the film over time. so far works ok at prevention of future rusting.