EXACTAMUNDO!!!!!!!! This has been the case for me since I strated claying 4 years ago.

 

You absolutely need dishwashing soap somtimes.
Actually it is what I use. Dishwashing soap and water will work well. The only reason they tell you not to use dishwashing soap is because it strips some polishes. Sal Zaino said it will never harm the paint though, so it is ok. Some guys who clay live by this method.

He actually recommends using Zaino Car wash with water as a lubricant. But any car wash will do "To use the clay bar, you spray a water-based lubricant (1/2 a cap of Z-7 Show Car Wash with 16 ounces of water) on a small area of your car and rub the bar back and forth with light to medium pressure"

 

Try this. After washing and drying your car put your hand inside a sandwich bag and run your fingers across the paint. You will feel all the things that have bonded to the paint, and also all the things that the claybar will remove.

 

I'm new to the claybarring thing, but all I know is that I dawn washed my car, then used "the perfect finish" (or something like that) brand claybar/lube. The lube was basically spray wax. This process got rid of a haze that was on my hood previously, and (along with maguires show car wax and blackfire) made my car look better than the day I got it at the dealership.

Go claybars!