My seat belts were really faded at the top and fairly stiff.
I didn't take before pics but looked for the best I had. In my full interior pic, look at the far shoulder strap to see how faded they were. They were light gray.
I washed them very well with Dawn and Borax then rinsed and then washed again then hose sprayer rinsed.
I used 1.3 oz of True Black from here
https://www.dharmatrading.com/dyes/dharma-acid-dyes.htmlI used the suggested amount of ammonium sulfate.
I should have used 1/2 cup of vinegar and did initially but reading that sometimes you need to add more vinegar if it is too light, I added at least another 1/2 cup after 30 minutes to ensure everything went right.
1 hour total time on the stove. This will stain grout, stone tile, everything, be careful.
30 minutes in, I used rubber gloves and slid all the slideables so the dye would work it's way in their too.
The next day I rinsed a few times in cold water then the following day dipped in the sink mixed with a pump of hair conditioner to soften them up. They turned out better than I thought they would after watching half fail Youtube videos. I think they don't clean them well or don't follow directions well.
