This information provides repair recommendations and general guidelines for steel classified as Ultra High Strength Dual Phase Steel (Dual Phase Steel with a tensile strength greater than 800 MPa), also known as DPX.
General Motors recommends the following when repairing or replacing this type of steel during collision repair.
Note:
Recommended Repairs:
Special Tools and Equipment

Mild Steel
Frame and UnderbodyHood
To open the hood:
1. Pull up on the hood release handle. It is located inside the vehicle to the
left of the steering column.
2. Go to the front of the vehicle and push the secondary hood release handle
toward the driver side of the vehicle.
3. Lift the hood and release the hood prop fr ...
Removal Procedure
Warning: Refer to Glass and Sheet Metal Handling Warning in the Preface
section.
Disable the SIR System. Refer to SIR Disabling
and Enabling.
Disconnect the negative battery cable. Refer to Battery Negative Cable
Disconnection and Connection.
Remove the front side door. Refer t ...
Installation Procedure
Clean and prepare the attaching surfaces for welding.
Apply one-part windshield urethane adhesive as noted from the original
panel.
Position the roof panel (1) on the
vehicle.
Verify the fit of the panel.
Clamp the panel into position.
Spot weld accor ...