LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> GMC >> 2021 >> Yukon AT4 >> Repair and Diagnosis >> Engine Mechanical >> Exhaust System >> Specifications >> Fastener Specifications
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Fastener Specifications

GM5613415Courtesy of GENERAL MOTORS COMPANY
Catalytic Converter Brace Bracket

Callout Component Name Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
1 Catalytic Converter Brace Bracket Nut [ 4x ] - - 22 N.m (16 lb-ft) Catalytic Converter Brace Bracket Replacement - Front 
2 Catalytic Converter Brace Bracket Nut [ 4x ] - - 22 N.m (16 lb-ft) Catalytic Converter Brace Bracket Replacement - Middle (Nitrogen Oxides Catalytic Converter) , or Catalytic Converter Brace Bracket Replacement - Middle (Block) 
3 Catalytic Converter Brace Bracket Nut [ 2x ] - - 22 N.m (16 lb-ft) Catalytic Converter Brace Bracket Replacement (LM2 Engine Block to Exhaust Back Pressure Valve) 
4 Exhaust Front Pipe Nut [ 2x ] - - 50 N.m (37 lb-ft) Catalytic Converter Brace Bracket Replacement (LM2 Engine Block to Exhaust Back Pressure Valve) 
GM5614900Courtesy of GENERAL MOTORS COMPANY
Catalytic Converter Brace Bracket (Engine Block to Nitrogen Oxides Catalytic Converter)

Callout Component Name Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
1 Catalytic Converter Brace Bracket Bolt [ 2x ] - - 22 N.m (16 lb-ft) Catalytic Converter Brace Bracket Replacement (LM2 Engine Block to Exhaust Back Pressure Valve) 
GM5615029Courtesy of GENERAL MOTORS COMPANY
Catalytic Converter Brace Bracket- Front

Callout Component Name Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
1 Catalytic Converter Brace Bracket Bolt [ 2x ] - - 22 N.m (16 lb-ft) Exhaust Front Bracket Replacement 
2 Exhaust Hanger Bracket Nut - - 22 N.m (16 lb-ft) Exhaust Front Hanger Replacement 
GM5613443Courtesy of GENERAL MOTORS COMPANY
Catalytic Converter Brace Bracket-Rear Upper

Callout Component Name Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
1 Catalytic Converter Brace Bracket Nut [ 4x ] - - 22 N.m (16 lb-ft) Catalytic Converter Brace Bracket Replacement - Rear Upper (2WD with MQC) , or Catalytic Converter Brace Bracket Replacement - Rear Upper (4WD with MQC) 
GM5613461Courtesy of GENERAL MOTORS COMPANY
Catalytic Converter Clamp @ Nitrogen Oxides Catalytic Converter

Callout Component Name Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
1 Catalytic Converter Clamp Yes - 15 N.m (11 lb-ft) Nitrogen Oxides Catalytic Converter with Filter Replacement 
GM5613448Courtesy of GENERAL MOTORS COMPANY
Exhaust Back Pressure Valve

Callout Component Name Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
1 Catalytic Converter Nut [ 3x ] - - 50 N.m (37 lb-ft) Exhaust Back Pressure Valve Replacement 
2 Exhaust Gas Recirculation Valve Inlet Gasket Yes - - Exhaust Back Pressure Valve Replacement 
3 Exhaust System Front Gasket Yes - - Nitrogen Oxides Catalytic Converter Replacement 
4 Exhaust Front Pipe Nut - - 50 N.m (37 lb-ft) Nitrogen Oxides Catalytic Converter Replacement 
GM5522075Courtesy of GENERAL MOTORS COMPANY
Exhaust Front Underbody Heat Shield-Exhaust Intermediate Underbody Heat Shield

Callout Component Name Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
1 Exhaust Heat Shield Retainer [ 3x ] - - - Exhaust Front Underbody Heat Shield Replacement 
2 Exhaust Heat Shield Retainer [ 2x ] - - 2.5 N.m (2 lb-ft) Exhaust Front Underbody Heat Shield Replacement 
3 Exhaust Heat Shield Retainer [ 3x ] - - - Exhaust Intermediate Underbody Heat Shield Replacement (Short Wheelbase) , or Exhaust Intermediate Underbody Heat Shield Replacement (Long Wheelbase) 
4 Exhaust Heat Shield Retainer [ 3x ] - - 2.5 N.m (2 lb-ft) Exhaust Intermediate Underbody Heat Shield Replacement (Short Wheelbase) , or Exhaust Intermediate Underbody Heat Shield Replacement (Long Wheelbase) 
GM5656827Courtesy of GENERAL MOTORS COMPANY
Exhaust Front Underbody Heat Shield-Exhaust Intermediate Underbody Heat Shield (Long Wheelbase)

Callout Component Name Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
1 Exhaust Heat Shield Retainer [ 2x ] - - 2.5 N.m (2 lb-ft) Exhaust Front Underbody Heat Shield Replacement 
2 Exhaust Heat Shield Retainer [ 3x ] - - 2.5 N.m (2 lb-ft) Exhaust Front Underbody Heat Shield Replacement 
3 Exhaust Heat Shield Retainer [ 5x ] - - 2.5 N.m (2 lb-ft) Exhaust Intermediate Underbody Heat Shield Replacement (Short Wheelbase) , or Exhaust Intermediate Underbody Heat Shield Replacement (Long Wheelbase) 
4 Exhaust Heat Shield Retainer [ 3x ] - - 2.5 N.m (2 lb-ft) Exhaust Intermediate Underbody Heat Shield Replacement (Short Wheelbase) , or Exhaust Intermediate Underbody Heat Shield Replacement (Long Wheelbase) 
GM5517290Courtesy of GENERAL MOTORS COMPANY
Exhaust Heat Shield

Callout Component Name Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
1 Exhaust Heat Shield Retainer [ 2x ] - - - Exhaust Heat Shield Replacement 
2 Exhaust Heat Shield Retainer [ 2x ] - - - Exhaust Heat Shield Replacement 
GM5626995Courtesy of GENERAL MOTORS COMPANY
Exhaust Manifold (LM2)

Callout Component Name Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
1 Exhaust Manifold Flange Bolt [ 12x ] - Yes Exhaust Manifold Flange Bolt Torque Sequence (LM2)  Exhaust Manifold Replacement (LM2) 
2 Exhaust Manifold Gasket Yes - - Exhaust Manifold Replacement (LM2) 
3 Turbocharger Gasket Yes - - Compressor Air Intake Turbocharger Replacement
GM5626993Courtesy of GENERAL MOTORS COMPANY
Exhaust Manifold Heat Shield (LM2)

Callout Component Name Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
1 Exhaust Manifold Heat Shield Bolt [ 2x ] - - 10 N.m (89 lb/in) Exhaust Manifold Heat Shield Replacement (LM2) 
GM5620356Courtesy of GENERAL MOTORS COMPANY
Exhaust Manifold Heat Shield-Exhaust Manifold- Left Side (L84, L87)

Callout Component Name Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
1 Exhaust Manifold Heat Shield Bolt [ 3x ] - - 9 N.m (80 lb/in) Exhaust Manifold Heat Shield Replacement - Left Side 
2 Exhaust Manifold Bolt [ 5x ] Yes Yes First Pass: 27 N.m (20 lb-ft)
Second Pass: Loosen 180 degrees Final Pass: 23 N.m (17 lb-ft)		 Exhaust Manifold Replacement - Left Side 
3 Exhaust Manifold Gasket Yes - - Exhaust Manifold Replacement - Left Side 
GM5871503Courtesy of GENERAL MOTORS COMPANY
Exhaust Manifold- Right Side (L84, L87)

Callout Component Name Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
1 Exhaust Manifold Gasket Yes - - Exhaust Manifold Replacement - Right Side 
2 Exhaust Manifold Bolt [ 5x ] Yes Yes First Pass: 27 N.m (20 lb-ft)
Second Pass: Loosen 180 degrees Final Pass: 23 N.m (17 lb-ft)		 Exhaust Manifold Replacement - Right Side 
GM4992215Courtesy of GENERAL MOTORS COMPANY
Exhaust Manifold Heat Shield- Right Side (L84, L87)

Callout Component Name Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
1 Exhaust Manifold Heat Shield Bolt [ 3x ] - - 9 N.m (80 lb/in) Exhaust Manifold Heat Shield Replacement - Right Side 
GM5517286Courtesy of GENERAL MOTORS COMPANY
Exhaust Pipe Clamp @ Exhaust Muffler

Callout Component Name Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
1 Exhaust Pipe Clamp - - 28 N.m (21 lb-ft) Exhaust Muffler Replacement 
GM5642141Courtesy of GENERAL MOTORS COMPANY
Exhaust Rear Muffler (L84, L87)

Callout Component Name Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
1 Exhaust System Intermediate Nut [ 2x ] - - 22 N.m (16 lb-ft) Exhaust Rear Muffler Replacement (L84, L87, N10) , or Exhaust Rear Muffler Replacement (LM2, NB5) , or Exhaust Rear Muffler Replacement (L84, NB5) 
2 Exhaust System Rear Gasket Yes - - Exhaust Rear Muffler Replacement (L84, L87, N10) , or Exhaust Rear Muffler Replacement (LM2, NB5) , or Exhaust Rear Muffler Replacement (L84, NB5) 
GM5607596Courtesy of GENERAL MOTORS COMPANY
Exhaust Rear Muffler (LM2)

Callout Component Name Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
1 Exhaust Particulate Filter Nut [ 2x ] - - 22 N.m (16 lb-ft) Exhaust Rear Muffler Replacement (L84, L87, N10) , or Exhaust Rear Muffler Replacement (LM2, NB5) , or Exhaust Rear Muffler Replacement (L84, NB5) 
2 Exhaust System Rear Gasket Yes - - Exhaust Rear Muffler Replacement (L84, L87, N10) , or Exhaust Rear Muffler Replacement (LM2, NB5) , or Exhaust Rear Muffler Replacement (L84, NB5) 
GM5518423Courtesy of GENERAL MOTORS COMPANY
Exhaust Rear Muffler-Exhaust Rear Hanger (L84, L87)

Callout Component Name Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
1 Exhaust System Intermediate Nut [ 2x ] - - 22 N.m (16 lb-ft) Exhaust Rear Muffler Replacement (L84, L87, N10) , or Exhaust Rear Muffler Replacement (LM2, NB5) , or Exhaust Rear Muffler Replacement (L84, NB5) 
2 Exhaust System Rear Gasket Yes - - Exhaust Rear Muffler Replacement (L84, L87, N10) , or Exhaust Rear Muffler Replacement (LM2, NB5) , or Exhaust Rear Muffler Replacement (L84, NB5) 
3 Exhaust Hanger Bracket Bolt [ 2x ] - - 45 N.m (33 lb-ft) Exhaust Rear Hanger Replacement 
GM5642135Courtesy of GENERAL MOTORS COMPANY
Exhaust Rear Muffler-Exhaust Rear Hanger (LM2)

Callout Component Name Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
1 Rear Muffler Assembly Nut [ 2x ] - - 22 N.m (16 lb-ft) Exhaust Rear Muffler Replacement (L84, L87, N10) , or Exhaust Rear Muffler Replacement (LM2, NB5) , or Exhaust Rear Muffler Replacement (L84, NB5) 
2 Exhaust System Rear Gasket Yes - - Exhaust Rear Muffler Replacement (L84, L87, N10) , or Exhaust Rear Muffler Replacement (LM2, NB5) , or Exhaust Rear Muffler Replacement (L84, NB5) 
3 Exhaust Hanger Bracket Bolt [ 2x ] - - 45 N.m (33 lb-ft) Exhaust Rear Hanger Replacement 
GM5517298Courtesy of GENERAL MOTORS COMPANY
Exhaust Rear Underbody Heat Shield

Callout Component Name Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
1 Exhaust Heat Shield Retainer [ 3x ] - - 2.5 N.m (22 lb/in) Exhaust Rear Underbody Heat Shield Replacement 
2 Exhaust Heat Shield Retainer [ 3x ] - - Hand Tighten Exhaust Rear Underbody Heat Shield Replacement 
GM5509232Courtesy of GENERAL MOTORS COMPANY
Three-Way Catalytic Converter

Callout Component Name Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
1 Exhaust Front Pipe Nut [ 6x ] - - 50 N.m (37 lb-ft) Three-Way Catalytic Converter Replacement 
2 Exhaust Heat Shield Bolt - - 9 N.m (80 lb/in) Exhaust Front Pipe Heat Shield Replacement - Left Side 
3 Exhaust Heat Shield Bolt - - 9 N.m (80 lb/in) Exhaust Front Pipe Heat Shield Replacement - Right Side 
4 Exhaust System Seal Yes - - Three-Way Catalytic Converter Replacement 
5 Exhaust System Seal Yes - - Three-Way Catalytic Converter Replacement 
GM5614899Courtesy of GENERAL MOTORS COMPANY
Turbocharger Heat Shield

Callout Component Name Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
1 Turbocharger Heat Shield Bolt [ 2x ] - - 9 N.m (80 lb/in) Turbocharger Heat Shield Replacement 
2 Turbocharger Heat Shield Nut - - 9 N.m (80 lb/in) Turbocharger Heat Shield Replacement 
Exhaust Manifold Flange Bolt (LM2)
GM5136725Courtesy of GENERAL MOTORS COMPANY
Component Name [ Component Quantity ] Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
Exhaust Manifold Flange Bolt
[ 12x ]		 - - 30 N.m (22 lb-ft) Exhaust Manifold Replacement (LM2) 
Exhaust Manifold Bolt Torque Sequence - Left Side L84, L87
GM5652671Courtesy of GENERAL MOTORS COMPANY
Component Name [ Component Quantity ] Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
Exhaust Manifold Bolt [ 5x ] Yes - First Pass: 27 N.m (20 lb-ft)
Second Pass: Loosen 180 degrees Final Pass: 23 N.m (17 lb-ft)		 Exhaust Manifold Replacement - Left Side 
Exhaust Manifold Bolt Torque Sequence - Right Side L84, L87
GM5652672Courtesy of GENERAL MOTORS COMPANY
Component Name [ Component Quantity ] Single Use Fastener/Component Thread Locking Adhesive Required Specification Procedure
Metric (English)
Exhaust Manifold Bolt [ 5x ] Yes - First Pass: 27 N.m (20 lb-ft)
Second Pass: Loosen 180 degrees Final Pass: 23 N.m (17 lb-ft)		 Exhaust Manifold Replacement - Right Side 
scientia non olet · About LEMON Manuals