I've been using this for about 2 years and it collected so much dust and dirt I decided to wash it in warm water. Now everytime I wipe the Z it leaves a bit of brush streak behind. I'm going to wrap it in newspaper for a couple of days hopefully that will do the trick. Anyone use their Californi Car Duster for more than 2 years?

 

Mine is now 8 years old and works better than ever. The dirtier it gets the better it works. I have never washed mine. Maybe by doing that you took off the paraffin and now it isn't as effective.

 

You might have ruined it. From the California Duster FAQ:

How do I clean my Duster?

Because of a special permanently baked in paraffin treatment, The Original California Dusters are made to provide years of effective service without the need for cleaning. Simply shake them out before and after each use. The "dirtier" they get the better they work.

If you find it necessary to clean your Duster because it is too dirty or if the Duster stops lifting dust, it can be washed. You may hand wash your Duster in cold water with a mild detergent such as Woolite, then air dry. Do not use hot water to wash or hot air to dry, as heat or harsh detergent may remove the special paraffin treatment.

 

Mine left streaks too. My mom wanted it though, since you can't see the streaks on her white car.

DF towels are good for dusting...

 

The problem with using a towel to remove dust is that you're dragging it across the surface. As it picks up dust, your dragging the dust across the surface and that causes fine scratches or swirls.

The whole purpose of the Cali Duster is to pick up dust without having to drag something across your paint.