How To Replace Exhaust Manifold Bolts in a 1999-2006 Silverado

Sheared or broken exhaust manifold bolts can cause obnoxious exhaust leaks and unwanted, dangerous CO2 in the cabin of your Silverado. Follow this guide to replace the exhaust manifold bolts on your Silverado’s exhaust manifold.

Required Tools

  1. Vice grips
  2. Bolt extraction kit
  3. Right angle drill
  4. Welder
  5. Wrench or socket

Removal Procedure

  • Ensure your Silverado is cool to the touch to avoid the possibility of burning yourself.
  • Determine which exhaust manifold is emitting the exhaust leak. Once you locate the exhaust leak, remove the tire and wheel well for easy access.
  • Locate and remove the exhaust manifold bolts that are still in tact. There are six bolts total per exhaust manifold.

Caution: There is an heightened likeliness some bolts will break when removing them, so be careful and patient.

  • Once all of the bolts are removed, locate and remove the three nuts located on the flange where the manifold and exhaust connect.
  • Pull the exhaust manifold from the head.
  • Where the bolt broke off will determine the method used to extract the broken bolt(s). If the bolt is not flush with the head, vice grips will usually do the job. If the bolts are broken off flush with the head, you can either use an extraction kit and right angle drill, or weld a like-sized nut onto the exhaust manifold bolt, soak it in penetrating catalyst while it’s hot, and take it out with a socket or wrench.

Important: If none of the aforementioned techniques work, the head will have to be pulled and re-tapped.

Installation Procedure

1. Before installing the new exhaust manifold bolts, ensure all surfaces are clean before applying new flange and manifold gaskets.

Important: always use new hardware and gaskets, do no re-use old components.

2. Ensure the new hardware and bolt holes are clean to allow full thread engagement, and apply anti-seize to new hardware, starting at the fourth thread.

3. Position the new gasket and install the new hardware to the exhaust manifold.

Important: When installing the new exhaust manifold bolts, make sure to begin in the middle and work outward. The bolts should be torqued down to 18 ft/lbs when dry and clean. But with the use of anti-seize, the torque specs are lower. Over tightening or torqueing the new bolts unevenly could cause your manifold to crack.

4. Position the flange gasket and reconnect the exhaust to the exhaust manifold.

5. Start your Silverado to ensure proper installation of new hardware and there are no exhaust leaks. If you notice a leak, try tightening the exhaust manifold bolts until the leak disappears.

Nice job, you’re all done. Now you can drive your Silverado without that pesky exhaust leak.