Power Brake Booster for your 1991 GMC  GMC-3500-PICKUP (Vin:)

Mechanical Grading

• A = Grade Mechanical Parts "A" parts have less than 60,000 total miles, or if over 60,000 miles, must be less than 15,000 miles per model year of age. Example: An engine assembly with 50,000 miles.
• B = Grade Mechanical Parts "B" parts have equal to or greater than 60,000 and less than 200,000 total miles on them and have 15,000 miles or more per model year of age. "B" parts must have less than 200,000 total miles regardless of age. Example: A 2003 transmission assembly with 90,000 miles.
• C = Grade Mechanical Parts "C" parts have equal to or greater than 200,000 total miles on them regardless of age. Example: An engine assembly with 250,000 miles.

Body Part Grading

SHEET METAL BODY PARTS Grading is based on any necessary repair time required to make the panel "Clean and Undamaged". Damage is represented by unit amounts. A unit, (which is defined by a whole number) represents damage that can be covered by a credit card sized object.

• A = Grade Body Parts "A" grade parts are 1 unit or less of repair necessary. Example: A front door assembly with a parking lot ding in the center of the door (5P1). An entire front end or rear body sheet metal assembly in "A" condition will have three units or less of repair necessary. Example: A front end assembly with a creased in the hood (6C1) and dented fender (5D2).
• B = Grade Body Parts "B" grade parts are greater than 1 unit and 2 units or less of repair necessary. Example: A roof with hail damaged (5H2). An entire front end or rear body sheet metal assembly that is "B" grade will have 6 units or less (but more than 3 units) of total repair necessary on the entire assembly. Example: A front end assembly with collision damage (6E4) on the bumper and rust (7R2) on the fender.
• C = Grade Body Parts "C" grade parts are more than 2 units of repair necessary. Example: A bent tailgate (2E4). An entire front end or rear body sheet metal assembly that is "C" grade will have more than Page 11 6 units of total repair necessary on the entire assembly. Example: A rear clip with collision damage on the tailgate (4E4) and quarter panel (4J5). X Grade Body Parts An X graded part does not contain enough data for the information provider to grade the part.