GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

  1. Remove the timing chain tensioner shoe. Refer to Timing Chain Tensioner Shoe Replacement .
  2. Slide the crankshaft sprocket from the crankshaft sprocket snout, in order to gain slack in the timing chain to remove the lower timing chain guide.

  3. Object Number: 637770  Size: SH
  4. Remove the cylinder head access hole plug.

  5. Object Number: 637585  Size: SH
  6. Remove the lower timing chain guide bolts.
  7. Remove the lower timing chain guide from the engine.

Installation Procedure


    Object Number: 637585  Size: SH
  1. Position the lower timing chain guide to the engine.
  2. Notice: Refer to Fastener Notice in the Preface section.

  3. Install the lower timing chain guide bolts.
  4. Tighten
    Tighten the lower timing chain guide bolts to 12 N·m (107 lb in).


    Object Number: 637770  Size: SH
  5. Install the cylinder head access hole plug.
  6. Tighten
    Tighten the cylinder head access hole plug to 5 N·m (44 lb in).

  7. Install the crankshaft sprocket to the crankshaft sprocket snout.
  8. Align the marked link on the timing chain with the timing mark on the crankshaft sprocket.

  9. Install the timing chain tensioner shoe. Refer to Timing Chain Tensioner Shoe Replacement .