Maybe you could take them apart and use oven cleaner spray.

We had those grey grates on a stove from 1991. Couldn't wait to get rid of it as I could never get them clean. I would bet that Jennair is at least 30 years old. It's lived a good life and there's a reason cooktop grates are not grey anymore.

We had those, pale grey; dumped in boiling water with some Dawn dish soap and a bunch of baking soda, let simmer for 15 minutes. Pull out and wipe down.

I used oven cleaner on mine and they came out great.

If you get them down to are metal There are high temp exhaust manifold paints to spray them with. You can then bake them for several hours at your ovens highest temp after they dry. They don't come in contact with food. So food safe isn't a priority.

Happy Holidays to everyone! So many new ideas to try!! I think I have done oven cleaner before but I will try that again before the others! Thanks again- I will update with my progress!

chcck with someone who does powder coating on metal and see if that would be heat proof. https://coalpail.com/coal-forum/viewtopic.php?f=57&t=43113

I’ll be waiting to hear if anything works.

I use Ajax powder and steel wool on the grates but actual cooker area just sponge clean with soap.

Hi Everyone, Here's an update. I put on oven cleaner, wrapped them in foil and left them over night. I used SOS pads after that. Both helped a lot. The next day I tried putting them in boiling water with baking soda and soap. That also helped a lot. I would say they are about 90% better now. Only problem is that I managed to cause some sort of short in the stove during the process! So no we are trying to find a repair place that can fix our old stovetop. I am really hoping to fix it now that we have gotten it so clean! I will try the Ammonia and the Ajax next to try to get the remaining spots off before resorting to painting. Here is an updated photo.

Take the grates off and put them in the dishwasher when you do your daily dishes. Clean them before the stuff gets burned on.

That is an amazing result!!