The service bulletin below was issued on May 10, 1972, but is applicable to all newer generations of Corvette.
Subject: Removal of Haze or Film From the Inside Surface of Windshields and Other Body Glass
Model and Year: NA
Source: Chevrolet Dealer Service Information Bulletin
Bulletin No: 72-I-6
Date: May 10, 1972
TO: ALL CHEVROLET DEALERS
An oily film or haze may form on the inside surface of the windshield and other body glass surfaces on late model vehicles under certain conditions.
This film is due to the natural migration of certain ingredients used in manufacturing plastic interior components. These solvents or plasticizing agents are secreted from these plastic components when subjected to high ambient temperatures and subsequently condense on the relatively cooler surfaces of the vehicle such as the windshield and body glass. The condition will diminish as these ingredients are bled from the materials.
This film can best be removed by wiping the glass with a household glass cleaner containing ammonia. Then wipe the glass with a clean dry cloth or commercial wiping pad. if this type of glass cleaner is not available, vinegar may be substituted, but may leave a residual odor.
Due to the recurring nature of this film, periodic cleaning is required and is considered a normal maintenance function.
Chevrolet Motor Division
General Motors Corporation
Article ID: 1099
Created: January 12, 2015
Last Updated: January 12, 2015
Online URL: https://www.corvetteactioncenter.com/tech/knowledgebase/article/chevrolet-dealer-service-information-bulletin-removal-of-haze-or-film-from-the-inside-surface-of-windshields-and-other-body-glass-1099.html