Third Design
| • | Timing chains are identical to second design. |
| • | The camshaft position actuator sensors are a new design. |
| • | The camshaft position actuators incorporate new sensor wheels that correspond with the new design of camshaft position actuator sensors. |
Fourth Design
| • | New secondary timing drive chains, inverted tooth (IT) design |
| • | The camshaft position actuators incorporate new sprockets that correspond with the use of IT chains on the secondary timing drive system. |
| • | The intake camshaft position actuators are different for the left and right sides. |
| • | The left and right secondary timing drive guides are new due to the use of IT chains on the secondary timing drive system. |
| • | The intermediate timing drive sprockets are new due to the use of IT chains on the secondary timing drive system. |
| • | New fourth design IT primary timing drive chain |
| • | New fourth design IT crankshaft sprocket |
| • | Fourth design IT primary chain is not interchangeable with second and third design. |