Cleaning oil off concrete driveway.

Well I went down to the local store and bought some scrub brushes and a bottle of TSP. I sprayed on the stain, let it sit about 15 or 20 minutes. Then I used the bristle scrub brush with warm water, followed by rinse with hot water, and finally the garden hose. The end result was about 80-90% reduction in the original stain. A few more treatments and it should be pretty well removed. I ran out of time as it started to cool off. Thanks all for your help. Oh, and RustyRatRod, I am embarrassed to say as a car owner and major enthusiast, one item I do not own, is a pressure washer.............yet.