Face 450

What do you guys use to clean/restore the black to rubber mats? i've tried multiple things, but everytime i wash and scrub them...they dry to a faded gray color instead of the original deep black

ygmn

put matte tire dressing on them.
Let dwell for few mins
Then wipe up excess and buff with towel.

Face 450

wouldn't using tire dressing make it slippery though?

ygmn

USe a Matte one and like I said buff with towel.
There are other protectants designed for interior and can be slippy.

Secret is to use bare minimum product - spray your applicator not the floor mat.

It will be more slippery then when it was dirty and old looking but the matte finish type and buffing will help to remove any excess and slipperiness at a minimum.

Also I am guessing the mat has some sort of non slip texture/surface be it grooves or dimples or something.

These can be nice products:
Interior Detailer - Griot's Garage (griotsgarage.com)
Vinyl & Rubber Dressing (griotsgarage.com)
Education Tire & Trim Dressings (griotsgarage.com)

Meguiar's® Natural Shine® Protectant, 16 oz. (meguiarsdirect.com)
Meguiar's® Ultimate Protectant Spray, 15.2 oz. (meguiarsdirect.com)
Meguiar's® New Car Scent Protectant, 16 oz. (meguiarsdirect.com)