For 1990-2009 cars

#### Special Tools

EN 46111 Crankshaft Rotation Socket

1. Ensure that the crankshaft is in the stage one timing drive assembly position using the EN 46111 . Refer to Camshaft Timing Drive Chain Alignment Diagram.
2. Ensure that the camshaft sealing rings (1) are in place in the camshaft grooves.
3. Select the proper camshaft for the particular installation location. The ring placement is defined as follows:

3.1. | The number 2 identification ring for the right exhaust camshaft is machined off (1).

3.2. | The number 3 identification ring for the right intake camshaft is machined off (2).

3.3. | The number 2 and 5 identification rings for the right intake camshaft is machined off (3) - Fourth Design, Camshaft Timing Drive System.

3.4. | The number 1, 4 and 5 identification rings for the right exhaust camshaft is machined off (4) - Fourth Design High Output, Camshaft Timing Drive System.

4. Apply a liberal amount of lubricant GM P/N 12345501 (Canadian P/N 992704) or equivalent to the camshaft journals and the right cylinder head camshaft carriers.
5. Place the right intake and right exhaust camshafts in position in the right cylinder head.
6. Position the camshaft lobes in a neutral position with the flats on the back of the camshafts up and parallel (1) with the right cylinder head camshaft cover rail.
7. Observe the markings on the right cylinder head camshaft bearing caps. Each bearing cap is marked in order to identify its location. The markings have the following meanings:

• | The raised feature must always be oriented toward the center of the cylinder head.

• | The I indicates the intake camshaft.

• | The E indicates the exhaust camshaft.

• | The number 1, 3, 5 indicates the cylinder position from the front of the engine.

8. Apply a liberal amount of lubricant GM P/N 12345501 (Canadian P/N 992704) or equivalent to the camshaft bearing caps.
9. Install the camshaft bearing thrust caps in the first journal of the right cylinder head.
10. Install the remaining bearing caps with their orientation mark toward the center of the cylinder head.
11. Hand start all the camshaft bearing cap bolts.

Notice: Refer to Fastener Notice in the Preface section.

12. Tighten the camshaft bearing cap bolts in the sequence shown.

Tighten
Tighten the camshaft bearing cap bolts in sequence to 10 N·m (89 lb in).

13. Loosen the center intake camshaft bearing cap bolts (1, 2) and the center exhaust camshaft bearing cap bolts (3, 4).
14. Retighten the center camshaft bearing cap bolts (1, 2, 3, 4).

Tighten
Retighten the camshaft bearing cap bolts to 10 N·m (89 lb in).