Permatex 81775 Rust Treatment , 8 oz. , GRAY

Works wonders if you follow the directions on the bottle. I didn't and wasted at least 3/4 of the bottle through contamination of the liquid not used. overall, very easy to use, works great.

I've used this a quite few times to slow down or stop rust. Although it says it's not for automotive use, that is probably my most common application... It seems to work best if there is actually some rust on the surface. If the surface is super clean, you might as well use naval jelly, and/or an etching primer and finish the job right. But, for a quick and easy way to slow down or stop surface rust in hidden / non-critical areas, this works perfectly. The coating applied to non-rusty areas doesn't turn black, so you do have to paint over it if you want consistent color.

I have used this product for years on many vehicle, tools and yard equipment. Simply wire brush or scrape loose rust. Then brush on two or more coats. It is best to paint over it after it dries to prolong protection. Important to pour a small amount in a can or other container before starting or else you will contaminate and destroy the remaining product that will convert itself and never again be useful.Sort of like Ice Nine by Kurt Vonnegut Jr.

Great product.

Stops rust

Works exactly as advertised

Good stuff fair price

I bought this to try to clean up and recoat some rust on the frame of my 2005 Wrangler. Spent a great deal of time (often with the Jeep inconveniently out of service for several days as coatings dried) scraping, Dremel wire wheeling, applying the product, and top coat painting. Found that in a mere summer month areas were puffing up and discoloring as rust continued to form underneath. Tried on some easily accessible areas to do as perfect prep work as was possible only to find that again within a summer month spots continued to rust and eventually break through. I now suspect that the coating part of this product (perhaps because it was made to be applied in a water based solution) may have an affinity for moisture that actually makes rust worse.On the other hand it does sort of bubble and then change colors which gives the impression that it is doing something cool and useful. Also its effectiveness may have a lot to do with the make up of the steel that it is applied to. Having used this and the same paint on other miscellaneous items has shown mixed results with some rusting quickly and others looking good after a few months. I am now leery of any type of rust converter/encapsulator product, though perhaps with other brands or in other situations they work better.I think that a better, more consistent option for my situation would be good cleanup and some common rusty metal primer and appropriate paint (Rustoleum) from any hardware or home improvement store. I know that these will typically buy at least a couple years of protection on most surfaces and I can make touchups a part of any work I do.Based on a great deal of research another option is a moisture curing product (like POR15 and Chassis Saver) which can work extremely well and last a very long time, but may not always adhere well to smoother or less well prepped surfaces and have limited shelf lives and extreme sensitivity to contamination with moisture. Then there are rubberized undercoatings which can protect well, but can also crack over time, trapping moisture and contaminants. Thick coatings also make it difficult to accurately asses the condition of the metal underneath. I've also found that some people use an oil, grease, or wax type coating with great success, however these need to be re-applied regularly and will obviously make it difficult to go back to paint or any other coating.