Chevrolet 1994 Astro Passenger Owner's Manual page 276

Cleaning Vinyl
Use warm water and a clean cloth.
Rub with a clean, damp cloth to remove dirt. You may have to do it
more than once.
Things like tar, asphalt and shoe polish will stain if you don't get them
off quickly. Use a clean cloth and a solvent-type vinyl cleaner.
Cleaning the Top of the Instrument Panel
Use only mild soap and water to clean the top surfaces of the instrument
panel. Sprays containing silicones or waxes may cause annoying reflections
in the windshield and even make it difficult to see through the windshield
under certain conditions.
Care of Safety Belts
Keep belts clean and dry.
Glass
Glass should be cleaned often. GM Glass Cleaner (GM Part No. 1050427)
or a liquid household glass cleaner will remove normal tobacco smoke and
dust films.
Don't use abrasive clean' on glass, because tney may cause scratches.
Avoid placing decals on
me
inside rear window, since they may have to be
scraped off later. If abrasive cleaners are used on the inside of the rear
window, an electric defogger element may be damaged. Any temporary
license should not be attached across the defogger grid.
Cleaning the Outside of the Windshield,
Backglass and Wiper Blades
If the windshield is not clear after using the windshield washer, or if the
wiper blade chatters when running, wax or other material may be on the
blade or windshield.