im guessing the dirt/greese/whatever it is is comming from my hat grazing the roof when i get out..and now i have dirty splotches on the grey cloth...what could i use to get these out?
~Blake

 

Had a similar problem with a plant that my 6 year old brought home from school.
Used Rain-X window cleaner, (the stuff foams)
And let it soak for a couple of minutes.
Dab it with a clean rag and all was gone.
Hope this works for you.