Oil Eater Ultra Concentrated Cleaner & Degreaser - Professional Strength Original Formula (5 Gallon Bucket, Pack of 2) - Heavy Duty Industrial & Home Use for Garage, Kitchen, Workshop & Auto Detailing

This stuff works, it's just not fast and you do have to scrub. Since it's more "earth friendly" doesn't mean you should stick your mitts in it, this stuff will dry your hands out, so use some gloves. Most parts cleaners suggest using water based cleaners anyway.