This vehicle provides fastener dimensions using the metric system. Most metric fasteners are approximate in diameter to equivalent English fasteners. Make replacements using fasteners of the same nominal diameter, thread pitch, and strength.
A number marking identifies the OE metric fasteners except cross-recess head screws. The number also indicates the strength of the fastener material. A Posidrive® or Type 1A cross-recess identifies a metric cross-recess screw. For best results, use a Type 1A cross-recess screwdriver, or equivalent, in Posidrive® recess head screws.
GM Engineering Standards and North American Industries have adopted a portion of the ISO-defined standard metric fastener sizes. The purpose was to reduce the number of fastener sizes used while retaining the best thread qualities in each thread size. For example, the metric M6.0 X 1 screw, with nearly the same diameter and 25.4 threads per inch replaced the English 1/4-20 and 1/4-28 screws. The thread pitch is midway between the English coarse and fine thread pitches.
Fastener Strength Identification
The most commonly used metric fastener strength property classes are 9.8 and 10.9. The class identification is embossed on the head of each bolt. The English, inch strength classes range from grade 2 to grade 8. Radial lines are embossed on the head of each bolt in order to identify the strength class. The number of lines on the head of the bolt is 2 lines less than the actual grade. For example, a grade 8 bolt will have 6 radial lines on the bolt head. Some metric nuts are marked with a single digit strength identification number on the nut face.
The correct fasteners are available through GM SPO. Many metric fasteners available in the aftermarket parts channels are designed to metric standards of countries other than the United States, and may exhibit the following:
The metric fasteners on GM products are designed to new, international standards. The following are the common sizes and pitches, except for special applications:
Tire Pressure Light
For vehicles with the Tire Pressure Monitor System (TPMS), this light comes on
briefly when the engine is started. It provides information about tire pressures
and the TPMS.
When the Light Is On Steady
This indicates that one or more of the tires are significantly underinflated.
A Driver In ...
Wheel Replacement
Replace any wheel that is bent, cracked, or badly rusted or corroded. If wheel
nuts keep coming loose, the wheel, wheel bolts, and wheel nuts should be replaced.
If the wheel leaks air, replace it.
Some aluminum wheels can be repaired. See your dealer if any of these conditions
exist.
Your de ...
Definition of Danger, Warning, Caution, and Note
The diagnosis and repair procedures in a GM Service Manual contain both
general and specific Dangers, Warnings, Cautions, Notes or
Importants. GM is dedicated to the presentation of service information that
helps the technician to diagnose and repair the systems
necessary for the proper operat ...