January 31, 2012
The 6.6 L Duramax engine families utilize three different grades (thicknesses) of head gaskets that are also specific to which side of the engine they are being installed on. The table and images below will aid in identifying the proper head gaskets required for your specific application. Some head gaskets may not have the grade designation shown in Figure 2. In these instances, use the grade designation shown in Figure 1. The head gaskets listed below work in conjunction with the AP0045 and AP0046 Head Installation Kits.
| AP Part Number | Location (Figure 3 & 4) | Grade (Figure 1 & 2) | Compressed Thickness | OEM Part Number |
|---|---|---|---|---|
| AP0047 | Left (Driver Side) | A | 0.90-1.00 mm | 98045058 |
| AP0048 | Left (Driver Side) | B | 0.95-1.05 mm | 98045059 |
| AP0049 | Left (Driver Side) | C | 1.00-1.10 mm | 98045060 |
| AP0050 | Right (Passenger Side) | A | 0.90-1.00 mm | 98045055 |
| AP0051 | Right (Passenger Side) | B | 0.95-1.05 mm | 98045056 |
| AP0052 | Right (Passenger Side) | C | 1.00-1.10 mm | 98045057 |
Note: These gaskets should be replaced “like for like.” It is not recommended to install gaskets of a different thickness than what was originally equipped.