First Design 2007
Important: This design, called "First Design" in the 2007 parts catalog was used:
2007: Start of production in Cadillac CTS, SRX, STS and Buick LaCrosse.
| • | The camshaft position actuator sensors (1) are a new design. |
| • | The camshaft position actuators (2) incorporate new sensor wheels (3) that correspond with the new design of camshaft position actuator sensors. |
| • | The timing chains are identical to most 2005 and all 2006 applications. |
Second Design 2007 - Present
Important: This design, called "Second Design" in the 2007 parts catalog was used:
| • | 2007: Start of production in all applications except Cadillac CTS, SRX, STS and Buick LaCrosse. Those applications changed to this design mid-year. |
| • | New secondary timing drive chains (1), with inverted tooth (IT) design. |
| • | The camshaft position actuators (2) incorporate new sprockets (3) 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 (4 and 9) are new due to the use of IT chains on the secondary timing drive system. |
| • | The intermediate timing drive sprockets (5 and 8) are new due to the use of IT chains on the secondary timing drive system. |
| • | New intake camshafts, not shown. |
| • | New design IT primary timing drive chain (7), with revised chain pitch to reduce noise. |
| • | New design IT crankshaft sprocket (6), with revised chain pitch to reduce noise. |
| • | Second design 2007 IT primary chain is NOT interchangeable with 2007 first design. |
