GM Service Manual Online
For 1990-2009 cars only

Special Tools

J 39914 Serpentine Belt Tensioner Unloader

Removal Procedure

  1. Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement.
  2. Remove the air cleaner intake duct. Refer to Air Cleaner Inlet Duct Replacement.

  3. Object Number: 1309849  Size: SH
  4. Using J 39914 rotate the drive belt tensioner (8) to release the tension on the drive belt.
  5. Remove the drive belt from the right idler pulley (2).
  6. Carefully release J 39914 to relieve the drive belt tensioner spring tension.
  7. Remove J 39914 from the drive belt tensioner (8).

  8. Object Number: 1317238  Size: SH
  9. Loosen the drive belt tensioner bolt.
  10. Remove the drive belt tensioner and bolt together from the generator bracket.
  11. Separate the bolt from the drive belt tensioner once removed from vehicle.

Installation Procedure


    Object Number: 1317238  Size: SH
  1. Install the bolt to the drive belt tensioner.
  2. Caution: Refer to Fastener Caution in the Preface section.

  3. Install the drive belt tensioner and bolt as an assembly to the generator bracket. Tighten the bolt to 50 N·m (37 lb ft).

  4. Object Number: 1309849  Size: SH
  5. Insure the drive belt is properly centered on all the pulleys except the right idler pulley (3).
  6. Using J 39914 rotate the drive belt tensioner away from the drive belt.
  7. Install the drive belt to the right idler pulley (2).
  8. Carefully release J 39914 allowing the drive belt tensioner (8) to come in contact with the drive belt.
  9. Remove J 39914 from the drive belt tensioner (8).
  10. Inspect the drive belt to insure the belt is properly centered on all the pulleys (1-8).
  11. Install the air cleaner intake duct. Refer to Air Cleaner Inlet Duct Replacement.
  12. Install the air cleaner assembly. Refer to Air Cleaner Assembly Replacement.