I know everyone prefers liquid detergent because they feel that the powder might not break down in the wash and stick to their towels. However, I use Tide powder specifically for my car stuff because of this article I read from the North Face clothing gear website. North Face knows cloth and clothing, and you all might find this excerpt interesting.
"Be sure to zip all zippers, and close all Velcro® fasteners before you wash your jacket. Please use a mild powder detergent. Liquid detergents can leave a residue on your jacket that will interfere with the DWR performance. You can wash your jacket in a regular washing machine, in cold water, on a gentle cycle. Put it through the rinse cycle twice, to be sure the detergent residue washes out. You can dry your jacket in a low temperature dryer, and if necessary, use a cool iron. Do not use bleach or fabric softeners, dry clean, or store when wet. (top)"
A lot of people have talked about residues on their towels, and about using 5 or ten rinses. You might want to check out using a powder like Tide, which is supposed to be pretty good. I like it.
"Be sure to zip all zippers, and close all Velcro® fasteners before you wash your jacket. Please use a mild powder detergent. Liquid detergents can leave a residue on your jacket that will interfere with the DWR performance. You can wash your jacket in a regular washing machine, in cold water, on a gentle cycle. Put it through the rinse cycle twice, to be sure the detergent residue washes out. You can dry your jacket in a low temperature dryer, and if necessary, use a cool iron. Do not use bleach or fabric softeners, dry clean, or store when wet. (top)"
A lot of people have talked about residues on their towels, and about using 5 or ten rinses. You might want to check out using a powder like Tide, which is supposed to be pretty good. I like it.