Avalanche, Sierra, Silverado, C&K Series, 1999-2005

Oil Pan 1

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Removal & Installation



4.3L Engines
  1. Drain the engine oil.
  2.  
  3. Disconnect the negative battery cable.
  4.  
  5. Raise and support the vehicle.
  6.  
  7. Remove or disconnect the following:

    Oil pan skid plate bolts and plate, if equipped
     
    Engine oil and filter
     
    Crossmember bolts and bar
     
    On 4WD, the front differential carrier
     
    Battery cable bracket bolts.
     
    Starter
     
    Transmission cover
     
    Positive battery cable clip bolt
     
    Oil level sensor electrical connector
     
    Transmission
     
    Oil level sensor and discard
     
    Oil pan bolts and oil pan
     
    Oil pan gasket
     

  8.  

To install:

  1. Thoroughly clean all gasket surfaces,
  2.  
  3. Apply a 5 mm wide and 25 mm long bead of sealant to both the right and left sides of the engine front cover to engine block junction at the oil pan sealing surfaces.
  4.  
  5. Apply a 5 mm wide and 25 mm long bead of sealant to both the right and left sides of the crankshaft rear oil seal housing to engine block junction at the oil pan sealing surfaces.
  6.  
  7. Install or connect the following:

    Transmission
     
    New gasket
     
    Oil pan and new gasket
     
    Install the oil pan bolts and nuts, but do not tighten
     

  8.  
  9. Measure the pan-to-transmission housing clearance using a feeler gage and a straight edge. Use a feeler gage to check the clearance between the oil pan-to-transmission housing measurement points. If the clearance exceeds 0.011 in. (0.3 mm) at any of the 3 oil pan-to-transmission housing measurement points (1), then repeat the step until the oil pan-to-transmission housing clearance is within the specification. The oil pan must always be forward of the rear face of the engine block.
  10.  
  11. Install the oil pan bolts, nuts and reinforcements. Torque bolts in sequence to 18 ft. lbs. (25 Nm).

    Oil level sensor electrical connector
     
    Positive battery cable clip bolt
     
    Transmission cover
     
    Starter
     
    Battery cable bracket bolts.
     
    On 4WD, the front differential carrier
     
    Crossmember bolts and bar
     
    Engine oil and filter
     
    Oil pan skid plate bolts and plate, if equipped
     
    Negative battery cable
     

  12.  
  13. Refill the engine with oil.
  14.  

  1. Before servicing the vehicle, refer to the precautions in the beginning of this section.
  2.  
  3. Drain the engine oil.
  4.  
  5. Remove or disconnect the following:

    Negative battery cable
     
    Exhaust crossover pipe
     
    Torque converter cover, if equipped with automatic transmission
     
    Cooler lines from guides and the oil filter adapter
     
    Strut rods at the flywheel/flexplate cover, if equipped
     
    Strut rod at the front engine mounts, if equipped
     
    Starter assembly
     
    Front drive axle tube nuts and lower axle bushing bolts
     
    Oil pan bolts/nuts and reinforcements
     
    Oil pan and gaskets
     

  6.  

To install:

  1. Thoroughly clean all gasket surfaces
  2.  
  3. Install or connect the following:

    New gasket
     
    Oil pan and new gaskets
     
    Oil pan bolts, nuts and reinforcements. Torque bolts to 18 ft. lbs. (25 Nm)
     
    Front drive axle tube nuts and lower axle bushing bolts
     
    Starter
     
    Strut rod brackets at the front engine mounts
     
    Strut rods at the flywheel/flexplate cover
     
    Cooler lines into guides and oil filter adapter with new filter
     
    Torque converter cover, if equipped with automatic transmission
     
    Exhaust crossover pipe
     
    Negative battery cable
     

  4.  
  5. Refill the engine with oil.
  6.  

  1. Before servicing the vehicle, refer to the precautions in the beginning of this section.
  2.  
  3. Drain the engine oil.
  4.  
  5. Remove or disconnect the following:

    Negative battery cable
     
    Exhaust crossover pipe
     
    Torque converter cover, if equipped with automatic transmission
     
    Cooler lines from guides and the oil filter adapter
     
    Strut rods at the flywheel/flexplate cover, if equipped
     
    Strut rod at the front engine mounts, if equipped
     
    Starter assembly
     
    Front drive axle tube nuts and lower axle bushing bolts
     
    Oil pan bolts/nuts and reinforcements
     
    Oil pan and gaskets
     

  6.  

To install:

  1. Thoroughly clean all gasket surfaces
  2.  
  3. Install or connect the following:

    New gasket
     
    Oil pan and new gaskets
     
    Oil pan bolts, nuts and reinforcements. Torque bolts to 18 ft. lbs. (25 Nm)
     
    Front drive axle tube nuts and lower axle bushing bolts
     
    Starter
     
    Strut rod brackets at the front engine mounts
     
    Strut rods at the flywheel/flexplate cover
     
    Cooler lines into guides and oil filter adapter with new filter
     
    Torque converter cover, if equipped with automatic transmission
     
    Exhaust crossover pipe
     
    Negative battery cable
     

  4.  
  5. Refill the engine with oil.
  6.  

  1. Drain the engine oil.
  2.  
  3. Disconnect the negative battery cable.
  4.  
  5. Raise and support the vehicle.
  6.  
  7. Remove or disconnect the following:

    Oil pan skid plate bolts and plate, if equipped
     
    Engine oil and filter
     
    Crossmember bolts and bar
     
    On 4WD, the front differential carrier
     
    Battery cable bracket bolts.
     
    Starter
     
    Transmission cover
     
    Positive battery cable clip bolt
     
    Oil level sensor electrical connector
     
    Transmission
     
    Oil level sensor and discard
     
    Oil pan bolts and oil pan
     
    Oil pan gasket
     

  8.  

To install:

  1. Thoroughly clean all gasket surfaces,
  2.  
  3. Apply a 5 mm wide and 25 mm long bead of sealant to both the right and left sides of the engine front cover to engine block junction at the oil pan sealing surfaces.
  4.  
  5. Apply a 5 mm wide and 25 mm long bead of sealant to both the right and left sides of the crankshaft rear oil seal housing to engine block junction at the oil pan sealing surfaces.
  6.  
  7. Install or connect the following:

    Transmission
     
    New gasket
     
    Oil pan and new gasket
     
    Install the oil pan bolts and nuts, but do not tighten
     

  8.  
  9. Measure the pan-to-transmission housing clearance using a feeler gage and a straight edge. Use a feeler gage to check the clearance between the oil pan-to-transmission housing measurement points. If the clearance exceeds 0.011 in. (0.3 mm) at any of the 3 oil pan-to-transmission housing measurement points (1), then repeat the step until the oil pan-to-transmission housing clearance is within the specification. The oil pan must always be forward of the rear face of the engine block.

    Click image to see an enlarged view

    Fig. Oil pan bolt tightening sequence-4.3L engine

  10.  
  11. Install the oil pan bolts, nuts and reinforcements. Torque bolts in sequence to 18 ft. lbs. (25 Nm).

    Oil level sensor electrical connector
     
    Positive battery cable clip bolt
     
    Transmission cover
     
    Starter
     
    Battery cable bracket bolts.
     
    On 4WD, the front differential carrier
     
    Crossmember bolts and bar
     
    Engine oil and filter
     
    Oil pan skid plate bolts and plate, if equipped
     
    Negative battery cable
     

  12.  
  13. Refill the engine with oil.
  14.  

  1. Drain the engine oil.
  2.  
  3. Disconnect the negative battery cable.
  4.  
  5. Raise and support the vehicle.
  6.  
  7. Remove or disconnect the following:

    Oil pan skid plate bolts and plate, if equipped
     
    Engine oil and filter
     
    Crossmember bolts and bar
     
    On 4WD, the front differential carrier
     
    Battery cable bracket bolts.
     
    Starter
     
    Transmission cover
     
    Positive battery cable clip bolt
     
    Oil level sensor electrical connector
     
    Transmission
     
    Oil level sensor and discard
     
    Oil pan bolts and oil pan
     
    Oil pan gasket
     

  8.  

To install:

  1. Thoroughly clean all gasket surfaces,
  2.  
  3. Apply a 5 mm wide and 25 mm long bead of sealant to both the right and left sides of the engine front cover to engine block junction at the oil pan sealing surfaces.
  4.  
  5. Apply a 5 mm wide and 25 mm long bead of sealant to both the right and left sides of the crankshaft rear oil seal housing to engine block junction at the oil pan sealing surfaces.
  6.  
  7. Install or connect the following:

    Transmission
     
    New gasket
     
    Oil pan and new gasket
     
    Install the oil pan bolts and nuts, but do not tighten
     

  8.  
  9. Measure the pan-to-transmission housing clearance using a feeler gage and a straight edge. Use a feeler gage to check the clearance between the oil pan-to-transmission housing measurement points. If the clearance exceeds 0.011 in. (0.3 mm) at any of the 3 oil pan-to-transmission housing measurement points (1), then repeat the step until the oil pan-to-transmission housing clearance is within the specification. The oil pan must always be forward of the rear face of the engine block.
  10.  
  11. Install the oil pan bolts, nuts and reinforcements. Torque bolts in sequence to 18 ft. lbs. (25 Nm).

    Oil level sensor electrical connector
     
    Positive battery cable clip bolt
     
    Transmission cover
     
    Starter
     
    Battery cable bracket bolts.
     
    On 4WD, the front differential carrier
     
    Crossmember bolts and bar
     
    Engine oil and filter
     
    Oil pan skid plate bolts and plate, if equipped
     
    Negative battery cable
     

  12.  
  13. Refill the engine with oil.
  14.  

4.8L, 5.3L & 6.0L Engines

NOTE
The original oil pan gasket is retained and aligned to the oil pan by rivets. When installing a new gasket, it is not necessary to install new rivets. DO NOT reuse the oil pan gasket. When installing the oil pan, install a NEW oil pan gasket.

  1. Remove or disconnect the following:

    Negative battery cable
     
    Front differential if equipped with four wheel drive
     
    Under body shield from the vehicle
     
    Oil pan shield

    Click image to see an enlarged view

    Fig. Oil pan shield-4.8L, 5.3L and 6.0L engines



    Click image to see an enlarged view

    Fig. Cross brace-4.8L, 5.3L and 6.0L engines

     



    Cross brace if equipped
     
    Engine oil and filter
     
    Transmission-to-oil pan bolts
     
    Oil level sensor electrical connector
     
    Two front wiring harness retainer bolts
     
    Engine wiring harness retainer bolts from the engine oil pan
     
    Engine oil cooler pipe-to-oil pan bolt
     
    Transmission oil cooler pipe retainer and the bolt from the oil pan
     
    Closeout covers and bolts (one each side of engine)
     
    Engine mount bolts each side
     
    Oil pan
     

  2.  

To install:


NOTE
The alignment of the structural oil pan is critical. The rear bolt hole locations of the oil pan provide mounting points for the transmission bell housing. To ensure the rigidity of the powertrain and correct transmission alignment, it is important that the rear of the block and the rear of the oil pan must NEVER protrude beyond the engine block and transmission bell housing plane.



Click image to see an enlarged view

Fig. Apply sealant at these points at the front of the block-4.8L, 5.3L and 6.0L engines



Click image to see an enlarged view

Fig. Apply sealant at these points at the rear of the block-4.8L, 5.3L and 6.0L engines

  1. Apply a 0.20 in. (5mm) bead of sealant GM P/N 12378190 or equivalent 0.8 in. (20mm) long to the engine block. Apply the sealant directly onto the tabs of the front cover gasket that protrudes into the oil pan surface.
    NOTE
    Be sure to align the oil gallery passages in the oil pan and engine block properly with the oil pan gasket.

  2.  
  3. Pre-assemble the oil pan gasket to the pan. Install the oil pan bolts to the pan through the gasket.
  4.  
  5. Install or connect the following:

    Oil pan gasket
     
    Oil pan
     
    Oil pan bolts, finger-tight. Do not over tighten.
     
    Two lower bell housing bolts to position the oil pan correctly
     

  6.  
  7. Snug the lower bell housing bolt finger-tight. Do not over tighten. Tighten the oil pan-to-block and oil pan-to-oil pan front cover bolts to 18 ft. lbs. (25 Nm). Tighten the oil pan-to-rear cover bolts to 106 inch lbs. (12 Nm). Tighten the bell housing bolts to 37 ft. lbs. (50 Nm).

    Transmission oil cooler pipe retainer and the bolt to the oil pan
     
    Engine oil cooler pipe-to-oil pan bolt and tighten to 89 inch lbs. (10 Nm)
     
    Engine wiring harness retainer bolts to the engine oil pan
     
    Oil level sensor electrical connector
     
    Transmission-to-oil pan bolts and tighten to 41 ft. lbs. (55 Nm)
     
    Front differential, if equipped with four wheel drive
     
    Underbody shield
     

  8.  
  9. Lower the vehicle. Fill the engine with oil and install the engine oil filter.
  10.  
  11. Connect the negative battery cable.
  12.  


NOTE
The original oil pan gasket is retained and aligned to the oil pan by rivets. When installing a new gasket, it is not necessary to install new rivets. DO NOT reuse the oil pan gasket. When installing the oil pan, install a NEW oil pan gasket.

  1. Remove or disconnect the following:

    Negative battery cable
     
    On 4WD, the inner axle housing nuts and washers from the bracket
     

  2.  
  3. Support the front drive axle with a suitable jack.
  4.  
  5. On 4WD, remove the differential carrier lower and upper mounting bolts and nut.
  6.  
  7. Lower the front drive axle.
  8.  
  9. Remove the transmission cover bolt.
  10.  
  11. Remove the oil pan shield.

    Click image to see an enlarged view

    Fig. Oil pan shield-4.8L, 5.3L and 6.0L engines



    Click image to see an enlarged view

    Fig. Cross brace-4.8L, 5.3L and 6.0L engines



    Cross brace if equipped
     
    Engine oil and filter
     

  12.  
  13. If equipped with the 4L60-E automatic transmission, remove the transmission bolt and stud on the right side and the bottom bolt on the left side.
  14.  
  15. If equipped with the 4L80-E automatic transmission, remove the transmission converter cover bolts.
  16.  
  17. Remove the oil level sensor connector.
  18.  
  19. Remove the battery cable channel bolt.
  20.  
  21. Slide the channel pin out of the oil pan tab.
  22.  
  23. Remove the engine wiring harness and the positive battery cable clip.
  24.  
  25. Remove the engine oil cooler lines from the positive battery cable clip.
  26.  
  27. Remove the oil pan bolts and the oil pan.
  28.  

To install:


NOTE
The alignment of the structural oil pan is critical. The rear bolt hole locations of the oil pan provide mounting points for the transmission bellhousing. To ensure the rigidity of the powertrain and correct transmission alignment, it is important that the rear of the block and the rear of the oil pan must NEVER protrude beyond the engine block and transmission bellhousing plane.



Click image to see an enlarged view

Fig. Apply sealant at these points at the front of the block-4.8L, 5.3L and 6.0L engines



Click image to see an enlarged view

Fig. Apply sealant at these points at the rear of the block-4.8L, 5.3L and 6.0L engines

  1. Apply a 0.20 in. (5mm) bead of sealant GM P/N 12378190 or equivalent 0.8 in. (20mm) long to the engine block. Apply the sealant directly onto the tabs of the front cover gasket that protrudes into the oil pan surface.
  2.  
  3. Apply a 0.20 in. (5mm) bead of sealant GM P/N 12378190 or equivalent 0.8 in. (20mm) long to the engine block. Apply the sealant directly onto the tabs of the rear cover gasket that protrudes into the oil pan surface.
    NOTE
    Be sure to align the oil gallery passages in the oil pan and engine block properly with the oil pan gasket.

  4.  
  5. Pre-assemble the oil pan gasket to the pan. Install the oil pan bolts to the pan through the gasket.
  6.  
  7. Install or connect the following:

    Oil pan, gasket and bolts to the engine block. Snug the oil pan bolts finger-tight. Do not overtighten.
     

  8.  
  9. Install the transmission converter cover bolts until snug, if equipped with the 4L80-E automatic transmission.
  10.  
  11. Install the transmission bolt and stud on the right side and bottom side until snug, if equipped with the 4L60-E automatic transmission.
  12.  
  13. Snug the lower bellhousing bolt finger-tight. Do not overtighten. Tighten the oil pan-to-block and oil pan-to-oil pan front cover bolts to 18 ft. lbs. (25 Nm). Tighten the oil pan-to-rear cover bolts to 106 inch lbs. (12 Nm). Tighten the bellhousing bolts to 37 ft. lbs. (50 Nm).
  14.  
  15. Install the positive battery cable clip and bolt to the oil pan.
  16.  
  17. Install the engine oil cooler lines to the positive battery cable clip.
  18.  
  19. Install the engine wiring harness and the positive battery cable clip.
  20.  
  21. Slide the channel pin into the oil pan tab.
  22.  
  23. Install the battery cable channel bolt.
  24.  
  25. Install the oil level sensor connector.
  26.  
  27. Install the transmission cover.
  28.  
  29. Install the crossbar and tighten the bolts to 75 ft. lbs. (100 Nm).
  30.  
  31. If equipped, install the oil pan skid plate and tighten to 15 ft. lbs. (20 Nm).
  32.  
  33. Raise the front drive axle into position.
  34.  
  35. If equipped with 4WD, install the differential carrier upper mounting bolt and nut until snug. Do not tighten at this time.
  36.  
  37. If equipped with 4WD, install the differential carrier lower mounting bolt and nut and tighten to 75 ft. lbs. (100 Nm).
  38.  
  39. If equipped with 4WD, install the inner axle housing washers and nuts to the bracket and tighten to 75 ft. lbs. (100 Nm).
  40.  
  41. Remove tool Jack from the front drive axle.
  42.  
  43. Lower the vehicle. Fill the engine with oil and install the engine oil filter.
  44.  
  45. Connect the negative battery cable.
  46.  


NOTE
The original oil pan gasket is retained and aligned to the oil pan by rivets. When installing a new gasket, it is not necessary to install new rivets. DO NOT reuse the oil pan gasket. When installing the oil pan, install a NEW oil pan gasket.

  1. Remove or disconnect the following:

    Negative battery cable
     
    Front differential if equipped with four wheel drive
     
    Under body shield from the vehicle

    Click image to see an enlarged view

    Fig. Oil pan shield-4.8L, 5.3L, 6.0L

     
    Oil pan shield

    Click image to see an enlarged view

    Fig. Cross brace-4.8L, 5.3L, 6.0L

     
    Cross brace if equipped
     
    Engine oil and filter
     
    Transmission to oil pan bolts
     
    Oil level sensor electrical connector
     
    Two front wiring harness retainer bolts
     
    Engine wiring harness retainer bolts from the engine oil pan
     
    Engine oil cooler pipe to oil pan bolt
     
    Transmission oil cooler pipe retainer and the bolt from the oil pan
     
    Closeout covers and bolts (one each side of engine)
     
    Engine mount bolts each side
     
    Oil pan
     

  2.  

To install:


NOTE
The alignment of the structural oil pan is critical. The rear bolt hole locations of the oil pan provide mounting points for the transmission bellhousing. To ensure the rigidity of the powertrain and correct transmission alignment, it is important that the rear of the block and the rear of the oil pan must NEVER protrude beyond the engine block and transmission bellhousing plane.



Click image to see an enlarged view

Fig. Apply sealant at these points at the front of the block-4.8L, 5.3L, 6.0L



Click image to see an enlarged view

Fig. Apply sealant at these points at the rear of the block-4.8L, 5.3L, 6.0L

  1. Apply a 5 mm (0.20 in) bead of sealant GM P/N 12378190 or equivalent 20 mm (0.8 in) long to the engine block. Apply the sealant directly onto the tabs of the front cover gasket that protrudes into the oil pan surface.
  2.  
  3. Apply a 5 mm (0.20 in) bead of sealant GM P/N 12378190 or equivalent 20 mm (0.8 in) long to the engine block. Apply the sealant directly onto the tabs of the rear cover gasket that protrudes into the oil pan surface.
    NOTE
    Be sure to align the oil gallery passages in the oil pan and engine block properly with the oil pan gasket.

  4.  
  5. Pre-assemble the oil pan gasket to the pan. Install the oil pan bolts to the pan through the gasket.
  6.  
  7. Install the oil pan, gasket and bolts to the engine block. Snug the oil pan bolts finger tight. Do not overtighten.
  8.  
  9. Install the two lower bellhousing bolts to position the oil pan correctly.
  10.  
  11. Snug the lower bellhousing bolt finger tight. Do not overtighten. Tighten the oil pan-to-block and oil pan-to-oil pan front cover bolts to 25 Nm (18 ft. lbs.). Tighten the oil pan-to-rear cover bolts to 12 Nm (106 inch lbs.). Tighten the bellhousing bolts to 50 Nm (37 ft. lbs.).
  12.  
  13. Install the transmission oil cooler pipe retainer and the bolt to the oil pan. Install the engine oil cooler pipe to oil pan bolt. Tighten the nut to 10 Nm (89 ft. lbs.).
  14.  
  15. Install the engine wiring harness retainer bolts to the engine oil pan.
  16.  
  17. Connect the oil level sensor electrical connector.
  18.  
  19. Install the transmission to oil pan bolts. Tighten the bolts to 55 Nm (41 ft. lbs.).
  20.  
  21. Install the front differential if equipped with four wheel drive.
  22.  
  23. Install the under body shield on the vehicle. Lower the vehicle. Fill the engine with oil and install the engine oil filter.
  24.  
  25. Connect the negative battery cable.
  26.  


NOTE
The original oil pan gasket is retained and aligned to the oil pan by rivets. When installing a new gasket, it is not necessary to install new rivets. DO NOT reuse the oil pan gasket. When installing the oil pan, install a NEW oil pan gasket.

  1. Remove or disconnect the following:

    Negative battery cable
     
    Front differential if equipped with four wheel drive
     
    Under body shield from the vehicle

    Click image to see an enlarged view

    Fig. Oil pan shield-4.8L, 5.3L, 6.0L

     
    Oil pan shield

    Click image to see an enlarged view

    Fig. Cross brace-4.8L, 5.3L, 6.0L

     
    Cross brace if equipped
     
    Engine oil and filter
     
    Transmission to oil pan bolts
     
    Oil level sensor electrical connector
     
    Two front wiring harness retainer bolts
     
    Engine wiring harness retainer bolts from the engine oil pan
     
    Engine oil cooler pipe to oil pan bolt
     
    Transmission oil cooler pipe retainer and the bolt from the oil pan
     
    Closeout covers and bolts (one each side of engine)
     
    Engine mount bolts each side
     
    Oil pan
     

  2.  

To install:


NOTE
The alignment of the structural oil pan is critical. The rear bolt hole locations of the oil pan provide mounting points for the transmission bellhousing. To ensure the rigidity of the powertrain and correct transmission alignment, it is important that the rear of the block and the rear of the oil pan must NEVER protrude beyond the engine block and transmission bellhousing plane.



Click image to see an enlarged view

Fig. Apply sealant at these points at the front of the block-4.8L, 5.3L, 6.0L



Click image to see an enlarged view

Fig. Apply sealant at these points at the rear of the block-4.8L, 5.3L, 6.0L

  1. Apply a 5 mm (0.20 in) bead of sealant GM P/N 12378190 or equivalent 20 mm (0.8 in) long to the engine block. Apply the sealant directly onto the tabs of the front cover gasket that protrudes into the oil pan surface.
  2.  
  3. Apply a 5 mm (0.20 in) bead of sealant GM P/N 12378190 or equivalent 20 mm (0.8 in) long to the engine block. Apply the sealant directly onto the tabs of the rear cover gasket that protrudes into the oil pan surface.
    NOTE
    Be sure to align the oil gallery passages in the oil pan and engine block properly with the oil pan gasket.

  4.  
  5. Pre-assemble the oil pan gasket to the pan. Install the oil pan bolts to the pan through the gasket.
  6.  
  7. Install the oil pan, gasket and bolts to the engine block. Snug the oil pan bolts finger tight. Do not overtighten.
  8.  
  9. Install the two lower bellhousing bolts to position the oil pan correctly.
  10.  
  11. Snug the lower bellhousing bolt finger tight. Do not overtighten. Tighten the oil pan-to-block and oil pan-to-oil pan front cover bolts to 25 Nm (18 ft. lbs.). Tighten the oil pan-to-rear cover bolts to 12 Nm (106 inch lbs.). Tighten the bellhousing bolts to 50 Nm (37 ft. lbs.).
  12.  
  13. Install the transmission oil cooler pipe retainer and the bolt to the oil pan. Install the engine oil cooler pipe to oil pan bolt. Tighten the nut to 10 Nm (89 ft. lbs.).
  14.  
  15. Install the engine wiring harness retainer bolts to the engine oil pan.
  16.  
  17. Connect the oil level sensor electrical connector.
  18.  
  19. Install the transmission to oil pan bolts. Tighten the bolts to 55 Nm (41 ft. lbs.).
  20.  
  21. Install the front differential if equipped with four wheel drive.
  22.  
  23. Install the under body shield on the vehicle. Lower the vehicle. Fill the engine with oil and install the engine oil filter.
  24.  
  25. Connect the negative battery cable.
  26.  


NOTE
The original oil pan gasket is retained and aligned to the oil pan by rivets. When installing a new gasket, it is not necessary to install new rivets. DO NOT reuse the oil pan gasket. When installing the oil pan, install a NEW oil pan gasket.

  1. Remove or disconnect the following:

    Negative battery cable
     
    Front differential if equipped with four wheel drive
     
    Under body shield from the vehicle
     
    Oil pan shield
     
    On 2007 Avalanche, unbolt steering rack and hang downwards

    Click image to see an enlarged view

    Fig. Oil pan shield-4.8L, 5.3L and 6.0L engines



    Click image to see an enlarged view

    Fig. Cross brace-4.8L, 5.3L and 6.0L engines

     



    Cross brace if equipped
     
    Engine oil and filter
     
    Transmission-to-oil pan bolts
     
    Oil level sensor electrical connector
     
    Two front wiring harness retainer bolts
     
    Engine wiring harness retainer bolts from the engine oil pan
     
    Engine oil cooler pipe-to-oil pan bolt
     
    Transmission oil cooler pipe retainer and the bolt from the oil pan
     
    Closeout covers and bolts (one each side of engine)
     
    Engine mount bolts each side
     
    Oil pan
     

  2.  

To install:


NOTE
The alignment of the structural oil pan is critical. The rear bolt hole locations of the oil pan provide mounting points for the transmission bell housing. To ensure the rigidity of the powertrain and correct transmission alignment, it is important that the rear of the block and the rear of the oil pan must NEVER protrude beyond the engine block and transmission bell housing plane.



Click image to see an enlarged view

Fig. Apply sealant at these points at the front of the block-4.8L, 5.3L and 6.0L engines



Click image to see an enlarged view

Fig. Apply sealant at these points at the rear of the block-4.8L, 5.3L and 6.0L engines

  1. Apply a 0.20 in. (5mm) bead of sealant GM P/N 12378190 or equivalent 0.8 in. (20mm) long to the engine block. Apply the sealant directly onto the tabs of the front cover gasket that protrudes into the oil pan surface.
    NOTE
    Be sure to align the oil gallery passages in the oil pan and engine block properly with the oil pan gasket.

  2.  
  3. Pre-assemble the oil pan gasket to the pan. Install the oil pan bolts to the pan through the gasket.
  4.  
  5. Install or connect the following:

    Oil pan gasket
     
    Oil pan
     
    Oil pan bolts, finger-tight. Do not over tighten.
     
    Two lower bell housing bolts to position the oil pan correctly
     

  6.  
  7. Snug the lower bell housing bolt finger-tight. Do not over tighten. Tighten the oil pan-to-block and oil pan-to-oil pan front cover bolts to 18 ft. lbs. (25 Nm). Tighten the oil pan-to-rear cover bolts to 106 inch lbs. (12 Nm). Tighten the bell housing bolts to 37 ft. lbs. (50 Nm).

    Transmission oil cooler pipe retainer and the bolt to the oil pan
     
    Engine oil cooler pipe-to-oil pan bolt and tighten to 89 inch lbs. (10 Nm)
     
    Engine wiring harness retainer bolts to the engine oil pan
     
    Oil level sensor electrical connector
     
    Transmission-to-oil pan bolts and tighten to 41 ft. lbs. (55 Nm)
     
    Front differential, if equipped with four wheel drive
     
    Underbody shield
     

  8.  
  9. Lower the vehicle. Fill the engine with oil and install the engine oil filter.
  10.  
  11. Connect the negative battery cable.
  12.  

4.8L, 5.3L, 6.0L & 6.2L Engines

NOTE
The original oil pan gasket is retained and aligned to the oil pan by rivets. When installing a new gasket, it is not necessary to install new rivets. DO NOT reuse the oil pan gasket. When installing the oil pan, install a NEW oil pan gasket.

  1. Remove or disconnect the following:

    Negative battery cable
     
    Front differential if equipped with four wheel drive
     
    Under body shield from the vehicle
     
    Oil pan shield
     
    On 2007 models (except Classic), unbolt steering rack and hang downwards

    Click image to see an enlarged view

    Fig. Oil pan shield-4.8L, 5.3L, 6.0L and 6.2L engines



    Click image to see an enlarged view

    Fig. Cross brace-4.8L, 5.3L, 6.0L and 6.2L engines

     



    Cross brace if equipped
     
    Engine oil and filter
     
    Transmission-to-oil pan bolts
     
    Oil level sensor electrical connector
     
    Two front wiring harness retainer bolts
     
    Engine wiring harness retainer bolts from the engine oil pan
     
    Engine oil cooler pipe-to-oil pan bolt
     
    Transmission oil cooler pipe retainer and the bolt from the oil pan
     
    Closeout covers and bolts (one each side of engine)
     
    Engine mount bolts each side
     
    Oil pan
     

  2.  

To install:


NOTE
The alignment of the structural oil pan is critical. The rear bolt hole locations of the oil pan provide mounting points for the transmission bell housing. To ensure the rigidity of the powertrain and correct transmission alignment, it is important that the rear of the block and the rear of the oil pan must NEVER protrude beyond the engine block and transmission bell housing plane.



Click image to see an enlarged view

Fig. Apply sealant at these points at the front of the block-4.8L, 5.3L and 6.0L engines



Click image to see an enlarged view

Fig. Apply sealant at these points at the rear of the block-4.8L, 5.3L and 6.0L engines

  1. Apply a 0.20 in. (5mm) bead of sealant GM P/N 12378190 or equivalent 0.8 in. (20mm) long to the engine block. Apply the sealant directly onto the tabs of the front cover gasket that protrudes into the oil pan surface.
    NOTE
    Be sure to align the oil gallery passages in the oil pan and engine block properly with the oil pan gasket.

  2.  
  3. Pre-assemble the oil pan gasket to the pan. Install the oil pan bolts to the pan through the gasket.
  4.  
  5. Install or connect the following:

    Oil pan gasket
     
    Oil pan
     
    Oil pan bolts, finger-tight. Do not over tighten.
     
    Two lower bell housing bolts to position the oil pan correctly
     

  6.  
  7. Snug the lower bell housing bolt finger-tight. Do not over tighten. Tighten the oil pan-to-block and oil pan-to-oil pan front cover bolts to 18 ft. lbs. (25 Nm). Tighten the oil pan-to-rear cover bolts to 106 inch lbs. (12 Nm). Tighten the bell housing bolts to 37 ft. lbs. (50 Nm).

    Transmission oil cooler pipe retainer and the bolt to the oil pan
     
    Engine oil cooler pipe-to-oil pan bolt and tighten to 89 inch lbs. (10 Nm)
     
    Engine wiring harness retainer bolts to the engine oil pan
     
    Oil level sensor electrical connector
     
    Transmission-to-oil pan bolts and tighten to 41 ft. lbs. (55 Nm)
     
    Front differential, if equipped with four wheel drive
     
    Underbody shield
     

  8.  
  9. Lower the vehicle. Fill the engine with oil and install the engine oil filter.
  10.  
  11. Connect the negative battery cable.
  12.  

5.0L & 5.7L Engines
  1. Drain the engine oil.
  2.  
  3. Remove or disconnect the following:

    Negative battery cable
     
    Underbody protector shields
     
    Transmission and engine oil lines from guides
     
    Front driveshaft, if needed
     
    Front drive axles, if needed
     
    Exhaust crossover pipe
     
    Flywheel/flexplate or torque converter cover
     
    Oil filter and adapter
     
    Strut rods at the front engine mounting, if equipped
     
    Oil pan bolts, nuts and reinforcements
     
    Oil pan and gaskets
     

  4.  

To install:

  1. Thoroughly clean all gasket surfaces.
  2.  
  3. Install or connect the following:

    New gasket
     
    Oil pan
     
    Oil pan bolts, nuts and reinforcements. Torque the bolts to 18 ft. lbs. (25 Nm).
     
    Strut rods at the front engine mounting
     
    Oil filter and adapter
     
    Torque converter or flywheel/flexplate cover
     
    Exhaust crossover pipe
     
    Front drive axles and driveshaft, if removed
     
    Transmission and engine oil lines to guides
     
    Underbody protectors
     
    Negative battery cable
     

  4.  
  5. Fill the crankcase with oil.
  6.  

  1. Before servicing the vehicle, refer to the precautions in the beginning of this section.
  2.  
  3. Drain the engine oil.
  4.  
  5. Remove or disconnect the following:

    Negative battery cable
     
    Under body protector shields
     
    Transmission and engine oil lines from guides
     
    Front driveshaft, if needed
     
    Front drive axles, if needed
     
    Exhaust crossover pipe
     
    Flywheel/flexplate or torque converter cover
     
    Oil filter and adapter
     
    Strut rods at the front engine mounting, if equipped
     
    Oil pan bolts, nuts and reinforcements
     
    Oil pan and gaskets
     

  6.  

To install:

  1. Thoroughly clean all gasket surfaces.
  2.  
  3. Install or connect the following:

    New gasket
     
    Oil pan and new gaskets
     
    Oil pan bolts, nuts and reinforcements. Torque bolts to 18 ft. lbs. (25 Nm)
     
    Strut rods at the front engine mounting
     
    Oil filter and adapter
     
    Torque converter or flywheel/flexplate cover
     
    Exhaust crossover pipe
     
    Front drive axles and driveshaft, if removed
     
    Transmission and engine oil lines to guides
     
    Under body protectors
     
    Negative battery cable
     

  4.  
  5. Fill the crankcase with oil.
  6.  

  1. Before servicing the vehicle, refer to the precautions in the beginning of this section.
  2.  
  3. Drain the engine oil.
  4.  
  5. Remove or disconnect the following:

    Negative battery cable
     
    Under body protector shields
     
    Transmission and engine oil lines from guides
     
    Front driveshaft, if needed
     
    Front drive axles, if needed
     
    Exhaust crossover pipe
     
    Flywheel/flexplate or torque converter cover
     
    Oil filter and adapter
     
    Strut rods at the front engine mounting, if equipped
     
    Oil pan bolts, nuts and reinforcements
     
    Oil pan and gaskets
     

  6.  

To install:

  1. Thoroughly clean all gasket surfaces.
  2.  
  3. Install or connect the following:

    New gasket
     
    Oil pan and new gaskets
     
    Oil pan bolts, nuts and reinforcements. Torque bolts to 18 ft. lbs. (25 Nm)
     
    Strut rods at the front engine mounting
     
    Oil filter and adapter
     
    Torque converter or flywheel/flexplate cover
     
    Exhaust crossover pipe
     
    Front drive axles and driveshaft, if removed
     
    Transmission and engine oil lines to guides
     
    Under body protectors
     
    Negative battery cable
     

  4.  
  5. Fill the crankcase with oil.
  6.  

5.7L Engines
  1. Before servicing the vehicle, refer to the Precautions section.
  2.  
  3. Drain the engine oil.
  4.  
  5. Remove or disconnect the following:

    Negative battery cable
     
    Under body protector shields
     
    Transmission and engine oil lines from guides
     
    Front driveshaft, if needed
     
    Front drive axles, if needed
     
    Exhaust crossover pipe
     
    Flywheel/flexplate or torque converter cover
     
    Oil filter and adapter
     
    Strut rods at the front engine mounting, if equipped
     
    Oil pan bolts, nuts and reinforcements
     
    Oil pan and gaskets
     

  6.  

To install:

  1. Thoroughly clean all gasket surfaces.
  2.  
  3. Install or connect the following:

    New gasket
     
    Oil pan and new gaskets
     
    Oil pan bolts, nuts and reinforcements. Torque the bolts to 18 ft. lbs. (25 Nm).
     
    Strut rods at the front engine mounting
     
    Oil filter and adapter
     
    Torque converter or flywheel/flexplate cover
     
    Exhaust crossover pipe
     
    Front drive axles and driveshaft, if removed
     
    Transmission and engine oil lines to guides
     
    Under body protectors
     
    Negative battery cable
     

  4.  
  5. Fill the crankcase with oil.
  6.  

6.5L Engine
  1. Drain the engine oil.
  2.  
  3. Remove or disconnect the following:

    Battery cables
     
    Oil dipstick
     
    Flywheel/flexplate cover
     
    Oil cooler line guides
     
    Front driveshaft
     
    Front axle, if needed
     
    Exhaust pipes from the manifolds
     
    Front engine mount through-bolts
     
    Oil pan bolts and the oil pan
     
    Oil pan rear seal
     

  4.  

To install:

  1. Clean all sealing surfaces.
  2.  
  3. Apply a 3 / 16 in. (5mm) bead of RTV sealant to the oil pan sealing surface, inboard of the bolt holes. The sealant must be wet to the touch when the oil pan is to be installed.
  4.  
  5. Install or connect the following:

    Oil pan rear seal
     
    Oil pan to the engine. Torque all bolts except the rear 2 bolts to 84 inch lbs. (9.4 Nm). Tighten the rear bolts to 17 ft. lbs. (23 Nm).
     
    Engine mounting through-bolt and nut
     
    Front axles and front driveshaft, if removed
     
    Oil cooler lines in guides
     
    Oil dipstick
     
    Exhaust pipes to the manifolds
     
    Flywheel/flexplate cover
     
    Battery cables
     

  6.  
  7. Refill with the proper grade and quantity of oil.
  8.  

  1. Before servicing the vehicle, refer to the Precautions section.
  2.  
  3. Drain the engine oil.
  4.  
  5. Remove or disconnect the following:

    Battery cables
     
    Oil dipstick
     
    Flywheel/flexplate cover
     
    Oil cooler line guides
     
    Front driveshaft
     
    Front axle, if needed
     
    Exhaust pipes from the manifolds
     
    Front engine mount through-bolts
     
    Oil pan bolts and the oil pan
     
    Oil pan rear seal
     

  6.  

To install:

  1. Clean all sealing surfaces.
  2.  
  3. Apply a 3 / 16 in. (5mm) bead of RTV sealant to the oil pan sealing surface, inboard of the bolt holes. The sealant must be wet to the touch when the oil pan is to be installed.
  4.  
  5. Install or connect the following:

    Oil pan rear seal
     
    Oil pan to the engine. Torque all bolts except the rear 2 bolts to 84 inch lbs. (9.4 Nm) Tighten the rear bolts to 17 ft. lbs. (23 Nm).
     
    Engine mounting through-bolt and nut
     
    Front axles and front driveshaft, if removed
     
    Oil cooler lines in guides
     
    Oil dipstick
     
    Exhaust pipes to the manifolds
     
    Flywheel/flexplate cover
     
    Battery cables
     

  6.  
  7. Refill with the proper grade and quantity of oil.
  8.  

  1. Before servicing the vehicle, refer to the precautions in the beginning of this section.
  2.  
  3. Drain the engine oil.
  4.  
  5. Remove or disconnect the following:

    Battery cables
     
    Oil dipstick
     
    Flywheel/flexplate cover
     
    Oil cooler line guides
     
    Front driveshaft
     
    Front axle, if needed
     
    Exhaust pipes from the manifolds
     
    Front engine mount through-bolts
     
    Oil pan bolts and the oil pan
     
    Oil pan rear seal
     

  6.  

To install:

  1. Clean all sealing surfaces.
  2.  
  3. Apply a 3 / 16 in. (5mm) bead of RTV sealant to the oil pan sealing surface, inboard of the bolt holes. The sealant must be wet to the touch when the oil pan is to be installed.
  4.  
  5. Install or connect the following:

    Oil pan rear seal
     
    Oil pan to the engine. Torque all bolts except the rear 2 bolts to 84 inch lbs. (9.4 Nm) Tighten the rear bolts to 17 ft. lbs. (23 Nm).
     
    Engine mounting through-bolt and nut
     
    Front axles and front driveshaft, if removed
     
    Oil cooler lines in guides
     
    Oil dipstick
     
    Exhaust pipes to the manifolds
     
    Flywheel/flexplate cover
     
    Battery cables
     

  6.  
  7. Refill with the proper grade and quantity of oil.
  8.  

  1. Before servicing the vehicle, refer to the precautions in the beginning of this section.
  2.  
  3. Drain the engine oil.
  4.  
  5. Remove or disconnect the following:

    Battery cables
     
    Oil dipstick
     
    Flywheel/flexplate cover
     
    Oil cooler line guides
     
    Front driveshaft
     
    Front axle, if needed
     
    Exhaust pipes from the manifolds
     
    Front engine mount through-bolts
     
    Oil pan bolts and the oil pan
     
    Oil pan rear seal
     

  6.  

To install:

  1. Clean all sealing surfaces.
  2.  
  3. Apply a 3 / 16 in. (5mm) bead of RTV sealant to the oil pan sealing surface, inboard of the bolt holes. The sealant must be wet to the touch when the oil pan is to be installed.
  4.  
  5. Install or connect the following:

    Oil pan rear seal
     
    Oil pan to the engine. Torque all bolts except the rear 2 bolts to 84 inch lbs. (9.4 Nm) Tighten the rear bolts to 17 ft. lbs. (23 Nm).
     
    Engine mounting through-bolt and nut
     
    Front axles and front driveshaft, if removed
     
    Oil cooler lines in guides
     
    Oil dipstick
     
    Exhaust pipes to the manifolds
     
    Flywheel/flexplate cover