Tools Required

WARNING: This page is about a different car, the 2007 Isuzu i-370, 2007 GMC Canyon, and 2007 Chevrolet Colorado. However, it is still accessible from the selected car via links, so may be relevant.

J 7872 Magnetic Base Dial Indicator Set

Fig 1: Measuring Camshaft Lobes

Courtesy of GENERAL MOTORS CORP.

Clean the camshafts with cleaning solvent.
Inspect the camshafts for the following conditions:
- Scored camshaft journals
- Damaged camshaft lobes
- Damaged camshaft sprocket locator slots
- Damaged threads
Measure the camshaft lobes using a micrometer. The intake camshaft lobes should be a minimum of 41.5 mm (1.635 in). The exhaust camshaft lobes should be a minimum of 41 mm (1.615 in).

Fig 2: Measuring Camshaft Runout & Lobe Lift

Courtesy of GENERAL MOTORS CORP.

Use J 7872 to measure the camshaft runout.
1. Set the camshaft in V-blocks between the centers.
2. Measure the intermediate camshaft journal.
Use J 7872 to measure the camshaft lobe lift.
1. Lubricate the camshaft to V-block contact areas with engine oil.
2. Set the camshaft on V-blocks.
3. Measure the camshaft lobe lift.
If the runout or camshaft lobe lift is not within specifications, replace the camshaft.