For service and parts needs, visit your dealer. You will receive genuine GM parts and GM-trained and supported service people.
Genuine GM parts have one of these marks:

Vehicle Care
California Proposition
65 WarningDriveline Working Angles Measurement
Special ToolsJ-23498-ADriveshaft Inclinometer, or equivalentJ-23498-20Driveshaft Inclinometer Adapter, or equivalentNote:This measurement procedure is intended to measure U-jointsworking angles only, not constant velocity (CV) joint or couplerassembly working angles.Note:This procedure is intended t ...