Piston Selection
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2012 GMC Yukon XL, 2012 GMC Yukon, 2012 Chevrolet Tahoe, 2012 Chevrolet Suburban, and 2012 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
- With a micrometer at a right angle, measure the piston outside diameter (OD). Measure the diameter 43 mm (1.69 in) from the top of the piston. Refer to Engine Mechanical Specifications (RPO LMG VIN 0) , Engine Mechanical Specifications (RPO L9H) , Engine Mechanical Specifications (RPO L94 VIN F) , Engine Mechanical Specifications (RPO L96 VIN G) , Engine Mechanical Specifications (RPO LC9 VIN 7) .
- Record the piston OD.
- Adjust the micrometer to the recorded piston OD.
- Insert the J 8087 bore gauge into the micrometer and zero the gauge dial.
- Using the J 8087 bore gauge, measure the cylinder bore inside diameter (ID). Measure at a point 64 mm (2.5 in) from the top of the cylinder.
- Record the cylinder bore ID.
- Subtract the piston OD from the cylinder bore ID in order to determine the piston-to-bore clearance. Refer to Engine Mechanical Specifications (RPO LMG VIN 0) , Engine Mechanical Specifications (RPO L9H) , Engine Mechanical Specifications (RPO L94 VIN F) , Engine Mechanical Specifications (RPO L96 VIN G) , Engine Mechanical Specifications (RPO LC9 VIN 7) .
- If the proper clearance cannot be obtained, select another piston and pin assembly and measure the clearances again. If the proper fit cannot be obtained, the cylinder bore may require honing for an oversize piston.
NOTE:
Measurements of all components should be taken with the components at normal room temperature. For proper piston fit, the engine block cylinder bores must not have excessive wear or taper. A used piston, pin, and connecting rod assembly may be installed if, after inspection is within specifications.