Customer has a 3 year old concrete driveway and a few months ago had a large spill of what he tells me is Power Steering Fluid. He tried brake cleaner and whatever degreaser he could find at the local big box store before he called me.
Went out to clean it on Monday with little success. I pre-treated with 50% EBC and let that sit for 20 minutes then surfaced cleaned (cold water - 8GPM, approx 2300 psi) a couple times. Treated again and surface cleaned a 3rd time.
Got out all the dirt, etc. in the driveway but the stain doesn’t appear any better. He also had big oil stain on the asphalt road in front of his house and that came out beautifully with the EBC and light pressure washing.
I could rent a 3.5 GPM, 3000 psi hot water PW and try again… What chems/process do you suggest? Is Power Steering Fluid special?
Here’s a pic from before I cleaned - don’t have a current pic but stain is basically unchanged.